How To Build A Home That Uses 80% Less Energy | PassivHaus UK Explained

What Is PassivHaus and why aren't we building every home this way?

Jimmy Webb sat down with Liam Schofield of LGS Airtightness for the latest episode of the UK Construction Podcast. This is an honest conversation about the state of British construction and why PassivHaus needs to become the standard.

Here's what they cover:

• What PassivHaus is and how it works in practice
• Why UK housing stock is the oldest and draughtiest in Europe
• How volume builder lobbying is slowing down energy standards
• The airtightness mistakes that get hidden before final inspection
• What the UK can learn from Ireland's approach
• The future of prefab construction
• How to get into high-performance building as a tradesperson

Years of experience, no filter, and a lot that the industry needs to hear.
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Transcript

From groundbreaking projects to game-changing innovations, the UK construction podcast brings you face-to-face with the industry's brightest minds and boldest thinkers. Each episode features candid conversations with construction leaders, architects, engineers, and on-site experts who share their hard-won insights and behind-the-scenes perspectives. We cut through the noise to deliver actionable intelligence on market trends, emerging technologies, and the forces shaping British building.

JIMMY: Liam, how we doing mate?

LIAM: How we doing, not bad, how are you?

JIMMY: Not too bad at all brother, thanks for coming on, appreciate it.

LIAM: Yeah, cheers for having me mate.

JIMMY: Good man, let's jump straight into it mate, tell us about yourself and your company.

LIAM: Yeah, so my name is Liam Schofield, I work in PassivHaus Construction, so it's all super energy efficient, air-soaked pumps, get involved a lot, solar panels, but I'm into the fabric first side of it, so making sure that they're insulated right, making sure they're airtight, make sure that it's all sealed up properly, rather than all with like the sexy bolt-on bits at the end that everyone loves. 

So I've been doing this for around 14 years now, started out in Newbuild PassivHaus, then moved into retrofit refurbishment, got a few quite complicated jobs in that, council jobs, maisonettes, all manner of different things. Yeah, and now after about 30-40 years, I sort of feel like I'm starting to kind of know what I'm on about every now and again.

JIMMY: That's good, so you decided to create a company because of it?

LIAM: Yeah, yeah, so I've always stopped contracting out of companies and then it's, when you're working for a smaller company, it's fine, no one's really bothered about qualifications or any of that sort of thing, but as you start going through, as you know yourself, getting through to the bigger companies, it's important to be a limited company.

It's important to have all of the right tickets, all the right cards, so yeah, it was around May of this year, so I've been working for another company for about three, four years, and it was just, things weren't great, so jobs were complicated, lack of organisation, and I'm going to, it's time to actually go on my own and make a go of it rather than hiding behind other people, as I have done my entire career. I'm like, nope, go as to the mast, I'm going for it.

JIMMY: Fair play, fair play. So what did you do before? How did you get into this?

LIAM: So I actually, well, I was at university in Lancaster and I had no idea what I wanted to do, so my degree was in educational research, I really thought that I wanted to be a teacher, then I did my dissertation, found out I can't stand kids on maths, and so that was a real problem.

JIMMY: Oh yeah, you know, this is what I'll do as a career, oh no, I hate them, I hate them all.

LIAM: So, meant to be a bit of a rejig, and instead what I ended up doing was staying in the job in a clothes shop that I did to pay my way through uni, then became the manager and buyer of that. 

And then the recession hit, everything was sort of going very wrong, and I was just fortunate, we just had a kid, just bought a house and everything, I was very fortunate that a guy came in and worked here, bought some stuff, and they were, oh I'm not from around this area, you know, he wants a labouring job, yeah, I'll do it, and so I made that jump, my boss in the clothes shop, she said, well, if you can be offered six months of work, I can guarantee you three weeks, so yeah, go and do it. 

So just as we got married, my final day in the clothes shop, then we got married, a little bit of a honeymoon and all that came back, and then that was my first day on site, and I've just never looked back since then.

JIMMY: Fair enough, fair play, I've just got to confirm though, you say you've had a kid, you don't hate that kid, do you?

LIAM: Oh no, I like my own kids, I've also grown to tolerate some of their friends, it's just en masse, it's entire groups.

JIMMY: Fair enough, yeah, it is a bit of, yeah, so you can just tell with some teachers that they don't like their job, and they're just in it for the money, you just tell, but yeah, you have got to like the kids and not the job, you're right.

LIAM: Yeah.

JIMMY: You mentioned PassivHaus, what is that?

LIAM: So that is a very strict energy standard, as it sounds like, and as most of these things are, comes from Germany, started in the early 90s, there's now 15,000 of them in the UK, so it's just a really strict energy standard, where the design is really thought of in advance, minimising the performance gap that always gets talked about in British housing in particular, where everything's meant to be insulated, and then it turns out that the house does not perform well, energy bills are really expensive, the idea of PassivHauss, all of that's engineered out, so you've got to keep an eye on the quality of the workmanship at all times. 

So my job now is, rather than the years of installing it, as it was, it's going around making sure that it's installed properly, doing the toolbox talks, doing the training, just making sure that people get used to PassivHaus, which is, so as I was saying before, you've got the insulation, you've got the air tightness, you've got a ventilation system with heat recovery. 

So that takes the incoming air, puts the warmth into that, so that you're not losing heat from the ventilation system, also triple glazed windows and doors, which is quite important, because even though a window and door is nowhere near as insulated as a wall, people enjoy being able to get in and out and have light. 

So we've got to deal with that, and then there's minimal thermal bridging, so you always see in, particularly in old buildings, you'll see condensation of mould in the corners, that's often because you've got a penetrating steel or a lintel, something like that, which is breaking through any insulation layer you've got, so that creates a condensation point, so that's what we're trying to get away from in PassivHaus, and that generally works, you're usually looking to be using roughly 80% energy less than you would be in a standard new build house.

JIMMY: Right, so that condensation thing you mentioned before, that's like a cold bridge thing, isn't it? Is it cold bridge?

LIAM: That's right, yeah. There's no real hard and fast rule to how you sort it out, because it depends on what's caused it in the first place, so in a lot of instances, like the house that I'm in right now, classic builder's house, I've lived in it for five years, so I'm absolutely bugger all with it. 

So if the door that I'm looking at now, I've got to wear extra socks because my back door has got a big crack down the middle of it, because it was never fitted, I didn't fit it, I hasten to add, but it was never fitted in the first place, so the door splays open, but what that means is on the internal bit of that reveal, we've got a little bit of mould because there's an air D of cold air that just sits there, and then it sits to the top of the board, there's another bit on our landing, and that's because basically that window has been fitted in a different way. 

Where I know for a fact it doesn't have any foam or anything down one side of it, so it's just got a bit of that plasterboard, and so that's gathering bits of black mould because it's that's where the cold air is coming through, so it gets to sit on that plasterboard and it stays there, so quite often it's a ventilation issue more than anything else if you've got black mould.

JIMMY: Yeah, so we'll touch on this in a bit actually, because I think that there's a lot that people probably are not aware of, particularly people who build these places, you know, instal these things, they're not aware of, but I mentioned to you on the phone a while back about me old man, that central heating, I thought I'd tell this little story, just to embarrass my old man, not that he'll ever listen, but he's never had central heating. 

So it used to have these all mounted three bar gas fires, and the gas cooker, so her heating engineer came around and he had to inspect all the carbon lots I don't think, and he said, look these are all ..., like you've got to condemn them. 

So he said, right rip them out, so he ripped all the heaters off the wall, and then he said the same with the cooker, right rip it out, so I said to him, right you're going to get central heating dad, uh nah, nah I'll be right, so it's just got these little sort of like portable gas bottle heaters, and it's just no good, so upstairs, particularly in my old bedroom, there's just fucking mould all over the walls everywhere, and I can't let the kids stay there, because they'll get bloody pneumonia or something, you know what I mean, so it's just a nightmare.

LIAM: No, well this is the thing with a lot of the sort of government policy, these really helpful things that get put out every year, how you can heat your house for less, always something like only heat the room you're in, no, no, if you only heat the room that you're in, you are ruining the fabric of your house, because it's good, you're going to get mould, you're going to get damp, you're going to get condensation. 

But the reason that that worked in the old days, is because you had a gas fire, because you had single glazed windows, because you had so much natural ventilation, it couldn't really build up, like you have loads of air going through the house at all times, you do that in a modern house, all you're doing is destroying the fabric of your house.

JIMMY: Yeah, but I think it affected me when I was a kid, I had pneumonia, mould pneumonia when I was a kid, and I think it was to do with the problem, like we had the old sash windows, and yeah, it just wasn't heated properly, it wasn't insulated properly, so I'm pretty sure my dad almost killed me.

LIAM: Yeah, yeah, yeah, that definitely sounds like murderous intent.

JIMMY: Well, maybe not intentional, but yeah, but so what is the difference between fencer and PassivHaus?

LIAM: So, well, fencer is what we, what we say for windows, isn't it? That's the standard, that's what you expect your window fitters to be accredited for, really, that it covers the glazing, it doesn't particularly cover the frame, it doesn't cover the installation quality, it's just, it's a very different standard. 

So, if you, if a company isn't fencer registered, then you have to go through that local building control to get it all signed off. So, fencers just, it's a tick box exercise, really, to make sure that things are signed off. In PassivHaus, there isn't actually a specific measure for checking that the windows have been installed properly, they just, as part of the QA process, you've got to evidence, like say, the amount of fixings that you've got going through the frame, the way that you've done your seal. 

So, it just sort of, everything in PassivHaus means it's just, it's naturally done correctly, it has to be done correctly, otherwise it can't get the face sign offs. So, the way you're looking at PassivHaus is that it's, everything is on a checklist, everything has to be itemised. So, you, I mean, there have been cases in PassivHaus where walls have had to be taken down because there isn't evidence that it's got the correct insulation behind it. 

So, before it can get certified, so, well, you haven't got any evidence that this is what it is, so we need, we need to see that. So, sections of the wall have to be taken out to evidence that the insulation is there. Everything is about making sure that it's been built as it was designed, making sure that the materials that have been used are as were specified. So, there isn't an escape route, there isn't a way around it.

JIMMY: I also think that the way that PassivHaus is done is the way that all buildings should be done.

LIAM: In theory, it is the way that all buildings are done. We've all got a QA process. Part L means that you've got to go around, you've got certain bits of the insulation that you've got to evidence are there. There is some ways, the part L one is even stricter because you have to have, it's got to be geotagged, date stamped, photographs. PassivHaus, they trust that it's a picture of what you say it's a picture of, and then the assessors come out and they do have a look, make sure. 

But that's the way that buildings should be done. We should be proving that we're doing the work correctly. There shouldn't be a way to lie. We shouldn't be able to leave a massive crater sized holes where we've got soil pipe going through. That should have to be sealed up and there should have to be proof that it's been sealed up before the plasterboard goes on the wall.

JIMMY: Yeah, yeah, yeah. I mean, there's no tolerance with it, is there?

LIAM: No. Basically, if you've got the design, you have to build it as per the design. You can't go, oh, well, we can't really work around this bit of insulation, so we just left it out. That will cause problems. You've got on the air tightness, you've got 0.6 air changes. So that means very basically every hour, 0.6 of the volume of the air of your building can leave through unintended leaks and drafts. 

In a standard house, that's roughly, roughly five air changes. There's a difference between air changes and air permeability. That's, we don't need to go into what that is. They sort of broadly for the purposes of this work out to be the same thing. So a massive house can be like 10 times better on air tightness than a standard build. 

But the gradient of difficulty of achieving that is massive. So going from 10 air changes to five air changes, bit of mastic, not leaving crater sized holes where you've got your soil pipes. Going down to three, you might have to start introducing a couple of membranes, thinking through the strategy. 

By the time you get to one, you're onto tapes, you're onto mastic, you're onto foams, you're onto a full plan before you even begin the work. When you go down to 0.6, it's all of that plus going back, rechecking, testing that that's all all right, fixing it up again, and then getting through your air test. It's not, it's very, very rare to just go straight away, bang, we've got our 0.6.

JIMMY: Yeah, I was going to say actually, because I was wondering how it could trip you up being this stringent, because we all know in construction that things don't often go to plan. So you have to adapt sometimes, you have to use your initiative to work your way around things. There's obviously no room for bodging, but I'm wondering how much adaptation you can do.

LIAM: There's little bits that you can do, little modifications if you just, you know the basics, you know that you can't have a projecting steel going through the insulation. You know, we have a three mil tolerance gap on all of the insulation. But one thing that I'm particularly keen on is when you, particularly when using a rigid insulation, there's sometimes a manufacturing defect in that board. We're meant to be doing this for the environment. 

Some people who were in this position will know you've got to throw that board in the skip. Sod that, it's one board out of hundreds, thousands potentially on a job. When we say that we've got an amount of an allowance for expanding foam to seal things up, for me that's where we're using the expanding foam. We're not forgiving sort of bad workmanship and bad detailing on a corner. 

The foam is there for if there's a defect in the material to stop it from going in a skip. It's not for getting away from bad workmanship. So you do get caught out by, just as sometimes new people come on site, they're getting talked to to go through any sort of training and toolbox talks. You just can't get it. Like some people, it doesn't mean that they're bad builders. It's nothing against the quality of their standard workmanship. It's just they cannot get the tolerances that are needed to work to. 

And you've got to, you've got to take them away from that bit of work, put them on something else. The main thing that catches you out on PassivHaus is that everyone's got a programme that they need to stick to. We all understand the programme. We've had conversations about what programme we're pricing and all that means in the past. 

And at the end of it, well, you've just got to get it done and got to get it handed over. In some instances, the programme just steamrollers the PassivHaus performance. And then at the end of it, they've got to get that signed over, can't get it signed over, or they've got problems with their final layer test. They're having to take down bits of wall. 

And then, so that time that you think that you're gaining back by rushing it through at the start, you're not, you're going to lose it at the end. Like usually you are going to lose it at the end.

JIMMY: And so it's a lot of it is some education of the wider system because British building is singularly bad in Europe with our entire process that we go through from tender right through to completion. No one's really checking up on any of it, right? An architect does their design. No one's really stress testing that design to make sure that it's entirely buildable.

LIAM: When the client takes on that design, they're not making sure that that properly works with what they want. When the builder gets involved, they're just, well, the design's there. Now they've got to work with that design. 

They're not thinking about all the little details that go along into that design because someone else, there's three people tendering for this job. One of those three, at least is going to... So they're thinking about how they can get the sort of money that they want, but not go too far. 

And so a load of things get missed in all of those stages. And then at the end of it, everyone signed up to something, but where do those costs come from? Is that timescale real? Like in fact, in any country where the building system is better, like in Germany, I've not got any first-hand experience of it, but people that I know who've worked here, it's a lot more collaborative. 

People who are involved at earlier stages, not really got this same thing of like the spectre of competitive tenders, which we all know aren't competitive tenders. People, the main contractor know who they want on that job, but for compliance, they've got to have another two people who are pricing for that so that it all looks above board. 

It's not, it doesn't mean anything and it's wasting two other companies' time. So that's because they know that they're not going to get the work, but they've still got to price for it. We're not getting anything realistic out of it. We all need to be working together to work out what these prices actually are, what the timescales actually are, how we can improve the performance. 

To go off on a complete aside, I can't understand how the government won't their sort of carbon emissions thing for 2030. And then I've completely ignored the fact that there is a building standard that exists. All of our new builds should just be PassivHaus. So that's not me saying it because like it's my job and I'll make money off it. 

It's just, it is a simple thing that yes, there is a steep learning curve to get onto PassivHaus. But once you're doing it, it's not hard. All PassivHaus is asking you to do is your job properly. That is literally all it is. The standard exists. We've got costs. Now we know that on average, it costs 8% more to build a PassivHaus than it does a standard new build, which yes, that's an appreciable cost. But even if you pass that onto the customer, sooner or later, there's got to be a loss of profit margin for volume builders. 

And let's make no bones about it. The reason PassivHaus has been slowed down is because of volume builders. They're the ones who've got the ear of government. It's not for no reason that they donate millions of pounds every year to whatever government's in control. It's because they're after their profits. 

They're making 35% profit. I don't know how true it is, but the thing we all hear about is that every fourth house on a house building job is free. That's their profit margin. I don't know how true that is. 

Don't sue me if it turns out that I'm wrong. That's my understanding of it. That's what's wrong. That profit margin needs to be lost. You and I will never be able to have that sort of profit margin. Why can they? And that's not the politics of envy or what have you. It's just basic economics. 

They're taking the piss and they're able to pay for that by lobbying government. And then housing standards go down. People are spending four, 500 grand on a new build house with a tiny little garden. But yeah, it's much better insulated than they were 10 or 15 years ago, but it's nowhere near what it could be for a very, very tiny fraction more money.

JIMMY: Yeah, that is. I mean, yeah, you mentioned a good point. Now I've got a big thing about this. All of these cramming houses into tiny plots and then the brick is throwing up, throwing the houses up like there's no craft in it anymore. 

And I used to speak to brickies and like, the conversation that I'd have with people are, oh, how many bits can you land a day? So it's all about getting them up, getting them up. And it's just, it's not right. I used to work for a small developer and he used to buy a plot of land, stick two houses on it. 

He might buy it for like 450 grand, stick two houses on it, sell them both 850 grand, 850 grand. But we'll be paving with these cheap three pound slabs and the windows would look cheap and tacky. I would actually say to him, how can you put the windows in mate? People are spending nearly a million pounds, but it's all about the money. It's all about the profit for everyone really.

LIAM: Yeah. Yeah, it is. There has to be another way around all of this. My other thing about PassivHauss and new build standard, we're also talking about retrofit, the need to refurbish houses, but British housing stock is the oldest, draughtiest in Europe, right?

Study after study have demonstrated that that's the case. But then what we're doing, well, every time that the green homes demand scheme, for example, it now turns out that loads of houses have been insulated wrong. And it's going to cost us millions, perhaps billions to put that right. 

But that's because no one actually really knows how to install internal and external wall insulation properly. So we had eco, we've got all of the accreditation schemes, but Trustmark doesn't act. Well, the proof is in the pudding now. That doesn't mean anything. That's just a bit of paper saying, yeah, they can do this work. 

But if you don't know what you're doing, you don't know what you're doing, right? And new build is a way that we can start training people on how to insulate stuff properly. New build is the way to slowly bring people in so that they actually know how to deal with the housing stocks that we've got. I spent a great number of years in this doing retrofit. 

And it is that there is a big step up again, the complication of it, making sure that you're not going to make someone's house rot down the line. It's stressful. There were jobs that I did at the start of my career that I'm sure they're fine because I've not heard anything about it unless they died because their floors collapsed. 

And that's why they've not got in touch. But literally 10, 12 years on, I wake up at two o'clock in the morning thinking about it because all the information, all of the best practice is always in flux. It's always changing. And there are things like where I've packed around joist ends. Sealed it up with sand and cement plaster. 

We don't do that anymore. It needs to be something breathable. But at the time that was on the architect's spec, we've all discussed it. We've all agreed that that's what we're doing. So I've done that. Honestly, more than once a fortnight, I will wake up and that will be on my mind.

JIMMY: Yeah, because it's really important. Someone has paid you to sort out their house. And now yeah, new information, but newer than when you did the job, but potentially sealed their house into rot. The thing is, though, I mean, that could be never ending. There's always going to be new research. 

There's always going to be new knowledge, isn't there? And I mean, it's the same with all the industry, like gas, you've got to do refresher courses and that sort of stuff. So you could just be worrying forever, really, couldn't you?

LIAM: Oh, yeah. Well, I think that's part of the mindset of it is we need people who actually worry about it. We need people who don't just drop the tools like that's me done for the day, never think about it again. 

People need to care. I don't know how we convince an industry to care, but I imagine it's not by turning building into an assembly line where all you ever do is fix skirting boards.

JIMMY: So how do we make PassivHaus the standard across the country then?

LIAM: It's either breaking that grip that the tier one contractors have got through lobbying. And by the way, I'm not having a go at tier ones. We need volumes of houses being built. They're the ones who've got the knowledge, the ability to do that. They're the ones who've got the links. What we really need to do is bring them along with us. 

But they need to have it demonstrated that there is a profit margin in PassivHaus, but they also need it from government to be pushed that that's it. We're going to up the standards. To massively paraphrase what happened in Ireland in the recession in 2010 — all their builders in the recession said the same as ours did. 

We can't afford to build. We need subsidies. We need help. Over here, we lowered energy standards. We delayed any improvements to energy standards to encourage them to get building again. In Ireland, they kept the same energy standards going through. And basically, when the volume builders said, well, we can't afford to build, we can't afford to build to these standards. 

The government more or less went, well, you were just telling us that you can't afford to build anyway. So you might as well not be able to afford to build to these standards. And then Ireland was absolutely leaps and bounds ahead of us, because they pushed on with it. 

They showed the builders, they just went, no, no, no, this is what you're doing now. And the builders had to do it, because at the end of the day, they want money. Obviously, we all want as much profit as we can get. But if that opportunity for additional profit is taken away, you're still going to do your job. You've still got shareholders. 

So you've got two options, haven't you? You either suck up having a lower profit margin, or you go bust. It's a bit of carrot and stick. We need to show the tier one companies, the house builders, that there is still money to be made in passive housing and energy efficiency. 

But also, the government needs to go, no, this is just how we're building now. They're doing it in Scotland. They've done it in a lot of Ireland. But the builders haven't gone away. The builders haven't shut up shop.

JIMMY: Well, now is the right time to introduce it, because you're getting your wish. They want to build 5 million houses, as everyone knows, in the near future. So you need to be speaking to whoever's in charge at the time, to get passive housing built into all of it.

LIAM: Yeah. We need to get Keir and Keir around the table. Well, yes. The two Keirs.

JIMMY: What other services do you provide?

LIAM: So it's largely air testing. Making sure that the house is airtight. I don't do the actual BISRIA certified going round rubber stamping the house. Not because I'm not interested in that. I can carry out the tests. I can give a number, but I'm interested in the going round and leak checking. I'm interested in the installing, the fiddling around with it. 

And there's a shady grey area where you're not allowed to mark your own homework. So if I'm going out, making the houses airtight, checking ventilation, everything like that, I can't then stick my fan in the door and go, oh, we've passed guys, great work. Someone else has got to go and do that. 

And so when I set up my company, I was looking at whether I wanted to go into doing compliance testing. 

And I don't, because that's the sort of thing where if I start doing it, that's going to end up being my job. And I find it incredibly boring. And there are people who derive enormous satisfaction from doing it. God knows why, but good for them. So I've got colleagues who I work with who do that side of air testing. I get them in as and when. 

But the area that I work mainly in now is on-site training, toolbox talks, quality assurance, going around, making sure that the work's being done correctly. 

Working as, in some cases, a bit of an intermediary between the design and the builders. Translation almost, because sometimes we could all be talking about the same thing, but we do it in a vastly different way.

JIMMY: Yeah. I mean that leads to what you mentioned earlier — there's no sort of connection between those in charge and people doing the work. The left hand is not communicating with the right properly. So you're that bridge.

LIAM: Yeah. I mean, this is it. It's a common refrain — just get people to do what we're telling them to do — because no one's actually telling them what to do. I do toolbox talks with apprentices on brickyard sites and they're putting up two skins of wall, fair enough with all the wall ties and that, but insulation is being treated as a separate thing. 

Nope. They're all the wall. That is the buildup of the wall. 

If you're building a wall with a cavity, just train them that it's got to be done at every stage. There's no joined up thinking. And trades are never taught the very simple thing that I've always worked to — always make it easier for the next person.

JIMMY: Yeah. The final bit of your work is making sure that the next person is going to have a simple time.

LIAM: Yeah. It's semi-selfish in a way. If you can make someone else's life easier, sooner or later, you're going to benefit too.

Again, PassivHaus is not some ethereal special thing for retrofit. It's just, these are things that we should all be doing. Our building standards will naturally go up if we just consider the other people that we try and bring along with us.

JIMMY: I really do think you're onto something there with PassivHaus. Yeah.

LIAM: I do. Particularly training and knowledge wise.

JIMMY: I mean, I used to be a groundworker for my cousin and his friend. But every now and again, we used to build extensions. And I never knew what I was doing, really. Basically, we put these walls up and put a bit of muck in there. Why am I doing that then? I never knew why I was doing it. I never knew if I was doing it properly. 

We just did it. And my cousin started doing it. And I don't think he knew either, respect to him. 

And he'd always lose money because he didn't know how to price properly. So he'd lose money on the projects. So he just said he'll just do the groundwork, get people in to do the frame and just do it that way. So I do think, yeah, you're right. There should be a standard where everyone is trained up and knows exactly what they're doing. 

Just knowing a little bit about other people's jobs and what they're going off to do.

LIAM: Oh, mate, honestly. Yeah. Going off on one a bit here. So I've been on a job doing the drainage for a house on a new build. The drainage comes out of the building, connects to the external manholes and then runs out to wherever. 

But the builders had decided to put the pipes in underground and take them out to position for me to connect to. Going down is really tight anyway, maybe a metre wide. So there's probably three or four pipes coming out the building down this run. 

I've got to get down full to go out to the front. 

But the front pipes are higher than the back pipes. So I've got a back fall. I've got to figure out how I'm going to get those with all different little angles. That's exactly it — they don't know my job, so they're not doing their job properly to help me.

JIMMY: Yeah. I think the first time I did any sort of drainage, I had no idea about the whole fall thing. I mean, obviously I know that it has to fall away. But I didn't think that there was such a thing as too much fall.

LIAM: Yes. Yes. So I thought, well, I'll help out. I ain't got anything else to do. I'll get this pipe working. Well, yeah, it's got that angle. What if it's making it to the drain? What difference does it make?

JIMMY: Yeah. That's not how that works. You're going to blow the back out.

LIAM: Yeah. So too much fall — the water separates from the turds and the turds won't flow away.

JIMMY: Basically, that was it. I thought, no, we're just turbo powering the turds. No, that's not how that works.

LIAM: Love it. Turbo power.

JIMMY: You mentioned something earlier — you don't want to go down the compliance route. So does the energy system fit in with compliance?

LIAM: Yeah, that's all separate. So you don't fancy doing the energy system side either?

JIMMY: Right.

LIAM: I like being on the tools. Even though I'm not actually very on the tools anymore, I'm still tools adjacent. But I'm happy with that. I occasionally get to get my hands dirty. I occasionally get to rifle through the shed because I need to get the kit out. But the moment you're completely office bound — it would make me a hypocrite if I went into that sort of thing, because my entire viewpoint on this is that there is nobody who is on the side of the boots on the ground. 

Everything is viewed from the design perspective. And then it's the builders who get the grief when things don't go right, even though no one's actually showing them how to do things right. That's the area that I want to work in. That's where I see there's a niche. That's where we need more work. 

And I want to bring people along with that. I want to train people up for doing the same thing, because there are a few of us who do this sort of thing. But a lot of builders just see it as an additional expense. So it's horribly titled, but the role is called a PassivHaus Champion — if anyone can think of a better name for it, because it makes me cringe. 

It was a very good friend of mine who coined the name and I've never truly forgiven him for it.

JIMMY: Oh, okay. Yeah. I can't come up with a different name for it. It's funny, because I mentioned to a couple of close friends that I'm interviewing you. One's a surveyor, and one's in building control. I showed one of them your LinkedIn page and he said, oh, he works at PassivHaus for us. And I said, no, he doesn't work for them. It's PassivHaus Champion. He just champions PassivHaus. 

And he was like — he's got ADHD — and he said when he was in uni, they had a PassivHaus speaker come in for a five hour presentation. Because of his ADHD he tends to zone out after about 20 minutes of anything. But he said he was just engaged the whole five hours. It was incredible. The best presentation he'd ever seen. So it must be quite interesting when you really dig into it.

LIAM: For a given value, it's absolutely fascinating. It's a Marmite thing. If you're into it, you are going to be properly into it. And when I'm doing the inductions, when I'm doing on-site training, you can see the ones who are going to do well. In fact, the guy who works with me now — I met him a couple of years ago. 

He was a labourer on the site I was on. Some people just have the right mind. I always got along with him chatting. And then when it came to needing assistance, I asked for Thomas. He's the right sort of person for me. When I'm training people on the leak testing and the air testing, I have what I call a mistake of training — I'll go, right, here's a smoke pen. The smoke pen is a little thing you press and smoke comes out. 

If you're depressurising, the smoke blows in from a hole. If you're pressurising, the smoke blows out to the hole. Simple. So it's, Thomas, right — here's your smoke pen. That's a hole. This is some tape. If the smoke does this, put some tape on it. If you can't put tape on it, put mastic on it. 

Right, training over, off you go. I do that with everyone because I want to see what they're actually capable of doing. Generally you've got to explain a bit more. Half an hour in, he was finding holes that I hadn't found.

JIMMY: Right. Well, I was thinking about this and maybe I should do this here.

LIAM: So he's worked with me now for two years. But he makes me look a right knob, because whenever I'm talking to someone about training, he goes, you don't train anyone. You just gave me a smoke pen. No, no, Thomas. I do train people. 

I had a really awkward moment where I was basically selling my services to someone and saying I do quite an intensive training thing. And he goes, no, you don't. Not now, Thomas. Not now.

JIMMY: Yeah. But sometimes simple is best. I like watching old stuff about — I don't know if you're into football — but Brian Clough.

LIAM: Oh, yeah. One of the greatest football managers in the world.

JIMMY: And he'd just say to them, there's the ball, there's the goal, get it in there. Keep the ball on the ground. If you're going to head the ball, try to make it look good. And that was it. And he'd win everything. Just keep it simple.

LIAM: Yeah. Yeah. Nice.

JIMMY: Right, what else we got here. Oh, common issues. What are some of the common issues you've seen in insulation and airtightness that might compromise the building?

LIAM: People hiding things. So you can generally tell whether a house is going to pass or fail its air test immediately by how well it's been mastic'd. If all of the skirting boards are immaculately mastic'd, it's going to fail — because they know they've done something wrong. They know they've got a problem. 

So they're trying to hide it at the final bit. And generally, if you go into a property where something's gone slightly off sequence — there's one section of wall which is suspiciously more advanced than everything else — that's because someone's done something wrong and they're hiding it. Always. There's never an innocent reason for one bit of a house to be more advanced than the rest of it. They know they've done something wrong and they've covered over it. 

Then you're faced with a couple of days of removal to find out what's underneath. So a lot of it is user error. But then you also have design issues — a steel that in two dimensions works perfectly but in a three dimensional reality doesn't have any bearing, and you've got to work around that. And then there's M&E. People putting in the wrong pipework, the wrong ductwork, people putting flexi ducts to MVHRs. 

In isolated cases you can use a little bit of flexi duct, sometimes there's no way around it. But I've seen MVHR systems where the entire route has been done in flexi duct. The reason you don't want flexi duct is because of that waggly-ness. An MVHR duct needs to be smooth on the inside, because the way it's handling the air, the way it's moving it — it's all attenuated, it's tuned. 

If you've got ridges in that pipe, it's stopping the airflow moving. So what you'll often find is the MVHR is noisy in practice. And that's because someone's put in flexi duct because they couldn't work out a way around it. It's largely people trying to save a few quid by going, well, I don't understand why it's got to be this way, and this is half the price. I'll put it in, no one will know.

JIMMY: I actually lived in a house for a period of time that had an air source heat pump. And the upstairs of the house never got warm. It was fully insulated, all that sort of thing. But the upstairs never got warm.

LIAM: I treasure my ignorance on plumbing, I'll be honest. It doesn't really interest me. But the micro bore pipes going up to all the radiators upstairs — you size pipes, the further away they get from the system for the flow and return. 

Micro bore pipes don't work with an air source heat pump at all, because it operates at quite a low temperature, it needs to be able to flow around properly. But yes — uninsulated micro bore pipes. That's why the radiators didn't work. No one knew. Buried under a floor. It's too late. If you want to sort that out, you're doing the job again. So it just had a cold upstairs.

JIMMY: And how old was this house?

LIAM: Well, the house itself was a 19th century farmhouse, but it had been retrofitted.

JIMMY: Right. Okay. So all of these cases, they all go back to what we were talking about — people not working to a recognised checklist, isn't it?

LIAM: Yeah. That's it. It's a simple thing, and I think it is something that all buildings should have. We talk about having checklists, we talk about having sign-overs, and we sort of do. But it doesn't ask, is this the correct pipe? So we have what we've been calling in work at the moment the permit to penetrate.

JIMMY: Boom boom. Oh yeah. No drill zone.

LIAM: But the point of that is, it's for when the M&E is going in — knowing that we've got all the pipes in the right place, knowing that before everything gets covered over, the right number of penetrations on that wall are there and accounted for. We've got a strategy of sealing them up, re-insulating them, everything like that. 

But that's the kind of thing we need to be looking at in normal building as well. Because normal building — I was sort of harsh on the house builders earlier, and my opinion of the energy standards — but they are getting better. We are slowly improving. But the more we improve the energy standards, the more we improve the insulation and the airtightness, the more these little details count. 

In Ireland, when they started really upping the standards in 2014 or so, they realised they were getting condensation and mould in houses that were massively outperforming the targets for airtightness and thermal efficiency. These houses were absolutely smashing it out of the park. 

The thing they didn't have was a ventilation strategy, because they were never meant to be building below three air changes. But they got that good at it, they started building to 1.5 to 1, without anyone really consciously realising what was happening. 

They were just getting better and better at it. And yeah, Ireland is now leaps and bounds ahead of us in ventilation, because they had to retrofit a load of their newish houses for a ventilation system that they never thought they'd need — because the builders had got so good at the standard they were working to that suddenly ventilation became a required thing.

JIMMY: Do you think there's enough education for homeowners or residents?

LIAM: No. Because for instance, I only found out this week — something came up on YouTube — that you can adjust your UPVC double glazed doors and windows to a summer and winter setting. There's a little thing on the side that you can turn to tighten the seals up.

JIMMY: Yeah. Tightening up the gasket. People don't know about that.

LIAM: Well, yes. But often double glazed units have been fitted so poorly that most of the adjustment doesn't actually work anyway. Your rails have been set wrong, so there's actually only one position you can put the door in. Things are getting better, but certain renowned window fitting companies are, in my experience, absolutely terrible at actually making a window fit properly.

JIMMY: Yeah. I mean, you can see that in some of the gaps. But what do we do with those little vents on the tops of the windows?

LIAM: Trickle vents are pretty important. They're actually a terrible way of doing what they're doing, but they're far better than nothing. It's quite a common thing for people to go, well, why would I want a cold draught through the top of my double glazing? But it is only a very small amount of airflow, and it keeps the air movement going. 

That's what will slow the condensation around your window reveals, because window reveals are always going to be a cold spot in a house. Even if you put expanding foam all around that window, you've got a step in the insulation because you'll generally have cavity insulation. And I forgot where I was going with that.

JIMMY: We talked about trickle vents and you went off about insulation.

LIAM: Yeah. So trickle vents — the whole point is they're creating an airflow. And that airflow is what stops things condensating. But what's the first thing you put in front of your windows?

JIMMY: Curtains or blinds.

LIAM: Yeah. So how is that airflow working now? And then it goes the other way — because what you've generally got under your window is a radiator. You've got your curtains going over a radiator. All of that warm air goes up into your window reveal, trickle vent on the top putting cold air in. 

All you're doing is creating this cycle of cold, hot air. And then it sort of makes it worse.

JIMMY: So what do we do with that then?

LIAM: It's just the way it is, unfortunately. That's what we've got at the moment. And if you've got a trickle vent, for God's sake leave it open. It's not doing a good job, but it's doing better than not having one. Always leave it open. If it's been designed properly, your trickle vents are only really in your wet rooms — your kitchen, your bathroom. 

Sometimes if people have really thought about it, you'll have them in the bedroom.

JIMMY: In case things get steamy.

LIAM: In case things get steamy. Yeah. Leave them open. There is always a better way of ventilating your house, but if you haven't got a ventilation strategy, they are critical.

JIMMY: Good. Yeah, I'll bear that in mind. So this is good education for anyone out there listening. So you're also a trustee of the Association of Environment Conscious Building?

LIAM: Well, I was, and I hope to be again — I'll find out on the 5th of December. I was for a few years. The Association of Environment Conscious Building — pre-dating all the PassivHaus stuff — has always been about making houses that are more sustainable, better for the environment. Straw bale houses, more natural building materials, just trying to make all construction have a lower footprint. 

It's been around since the eighties. It's a group of very passionate, caring people who just want building to be more ecologically sound. Things like reed beds for your waste, for example. Thinking about how we can work in tandem with the environment rather than just chucking a load of concrete down and building off the top of that. 

And then that's a complicated argument, because obviously concrete is terrible as far as carbon emissions go, but a concrete slab is essentially indestructible. 

It takes a lot of carbon to make, but it's going to be there until you decide you don't want it anymore. So how bad is it? It's the best thing for making a slab out of. Arguments like this get raised all the time because there isn't a simple answer to how we can make housing more energy efficient, or how we can sort out our environmental problems. 

We've been basing everything on carbon for years and years, but we've completely forgotten about the importance of biodiversity. You go down a real rabbit hole.

JIMMY: There are a lot of arguments for this, but a lot of counter-arguments as well. Valid on both sides, I think. The environment is a big, controversial topic. And I think you've got some right nasty sods on both sides of it. Even people who claim to be caring about the environment and they're not — like Drax in Yorkshire, wood pellets coming over from Canada and they're claiming that's good for the environment. 

It's not, is it? You've got a diesel boat coming halfway across the globe. Everyone's trying to push an agenda.

LIAM: I suppose I'm trying to push an agenda too. Everyone is. But it's whether people are doing it in good faith or bad faith. And a lot of these things have been done in bad faith.

JIMMY: Let's not go on about politicians.

LIAM: No, no. I've definitely said too much there. If that gets cut, I understand. To go back to the AECB — it's a bunch of very caring people who just want to do the right thing. They haven't been very good at pushing themselves forward, but that's the whole thing. 

If you try not to have an agenda, it's very difficult to get your voice heard, because you don't want to push yourself in case you're seen as pushing an agenda. 

So yeah, AECB is a bunch of nice people. I'd check them out. There are a lot of interesting resources on the website.

JIMMY: A trustee — what does a trustee do exactly?

LIAM: It's sort of like the board, as it were. You have a CEO and then trustees — I think there's 30 now. People in finance, a chairman, co-chair. It's almost like a board of directors.

JIMMY: So you were on the board and you're trying to get back on it. You've been a naughty boy and you've been kicked off basically.

LIAM: No, I didn't get kicked off. I left. There were conversations and then I left. Now I'm going back. I would like to go back.

JIMMY: Fair enough. I hope you do. I mean, I think you're probably quite forthright in what you say. I've noticed on LinkedIn you like to put it all out there every now and again. Sometimes people might not like it. Sometimes they do.

LIAM: Yeah. I'm not saying that I'm intelligent — I'm far from it. But lazy stupidity really annoys me. Anybody who uses the phrase "Rachel from accounts" — there is no situation after you've said that where you're not talking rubbish. Yeah, it's just the thing.

JIMMY: So you mentioned Thomas, who you work with. You've got a small team of four?

LIAM: Yeah. Yeah. There's four of us here and there.

JIMMY: It's good to keep it small sometimes, isn't it? You've got that intimacy. But you mentioned before that you're training them to all become part of the company — like part ownership?

LIAM: Yeah. That's my intention — I want everything to be part owned. They earn the same as me. And as it moves down the line, if we've got profits, there will be profit shares based on the amount of hours that have been done. Just trying to keep things equal, keep things fair. Because that's the way to get people engaged. 

The guys that I've got will be just as capable as me. Therefore they deserve the same amount of money. It's my company now, but I don't want it to be my company. It will be built off the backs of the people who work alongside me, and I want them to get the same benefits.

JIMMY: I think it's brilliant and everyone should be doing that. It makes sure everybody cares and helps everybody produce the best result and make sure you're all making money. But also it's like passing it on, isn't it? Did you watch that Brené Brown thing?

LIAM: I saw a small amount of it. Yeah. Fascinating. I need to watch more of that.

JIMMY: So for those listening — that reminds me of the Brené Brown podcast, the guest who was on Diary of a CEO. She spoke about the four forms of power. There's power to, where you give people power. Power within, where you're working on yourself. 

And then — let me get this right — power over, where you're trying to take it from people and want all the power for yourself. You get all the elites doing this, trying to instil fear. And then power with — which is what you're doing — where you're giving other people power, sharing it, and growing together. 

And I think that's really important. That is how we should all be living our lives. It'll make the world a better place.

LIAM: Yeah, definitely. That's what I want to have a part in. Sharing things out. Sharing the love. Dangerously socialist, but I think we get along better together, don't we? It's like the old pirate saying — we hang together or we hang separately.

JIMMY: Yeah. That's it.

LIAM: Yeah.

JIMMY: For homeowners or clients listening, how can they tell the difference between genuinely high quality airtightness work and something that only looks good on the surface?

LIAM: The simple answer to that is an air test. That's the simplest way. Or thermography surveys — that's another way of going about it. You get a thermal camera. There are actually some affordable ones that just go on the bottom of your smartphone. So it is possible to do that yourself. I'm also involved in the thermography testing and airtightness testing. 

The best way to find out if your house is performing the way you want it to is to have an air test. There are two different types. You have pulse testing — a big machine goes in the middle of your room, takes about 20 seconds, gives you an airtightness score. For new build, where you're just testing compliance and it's rinse and repeat, that's a very cheap way of getting your air test done. 

The other one is a blower door test, which is the sort that I do — you put the bag in the door with a fan in it, you depressurise the house, and then you go around with the smoke pens checking all your penetrations, window reveals, floors, intermediate floors — which are a common leak spot — loft hatches, back panels, all of those. 

If you're doing that with thermography, the best time is about three o'clock in the morning when it's coldest. 

You make your house as hot as you can get it so you've got the biggest temperature variable, and you're really showing up where you've got gaps in your insulation strategy and your airtightness strategy. 

Gaps in insulation and gaps in airtightness show up slightly differently on a thermal camera. If it's airtightness related, you get little fingers of blue. If it's an insulation issue, it tends to show up more as a blob or a straight line — because that's just cold transmission through a material rather than air movement.

LIAM: So sometimes when you — like say, if you were doing thermography on a steel, if that steel was going through to the outside, you might even be able to see the section of the steel as a cold section on the camera. That's sort of the basic ways of doing it. But also, sometimes you just know if your house isn't working right. 

You stop watching telly of an evening and your feet are cold, but if you put them up on the sofa they're all right. Because you've got a draught down at the low levels.

There are certain places where you'll move your living room around or move your bed around because you've noticed little draughts, because you've noticed that your head's cold when you're sat in that direction. Your body notices these things.

JIMMY: Yeah, you do. You get a sense of atmospheric pressure, don't you? It's like when you're in bed and someone opens the door downstairs, you just get a feel of the pressure change.

LIAM: Exactly that. And in a PassivHaus, it takes a little bit of getting used to the feeling of it because they are remarkably still. You're not feeling those pressure variables, because it's all a fully encapsulated sealed box. 

You're not feeling those movements in the same way. They're very quiet — if the MVHR is set up properly, which it should be, it's basically silent. They're just very calm, still places to be. I've actually known a couple of people who think they're bloody awful because of that stillness.

JIMMY: Strange. Yeah. I mean, I like it, but yeah, it is a peculiar sensation being in a PassivHaus at first. What about — I wasn't prepared for this question, actually. I'm just throwing it in here. Let me make sure I've got this right — I've done no research on it. I think it might be called Huf Haus? Is it in Germany? Huf Haus, prefabricated buildings.

LIAM: Oh yeah. What do I think of them? They're great. They're like prefab panel houses. They arrive on the back of a lorry, go up in about three days, and they're absolutely spotless. 

They're great. I actually worked on one — it wasn't a whole house, it was a Scandia Hus, I think. That was up on an island in Scotland called Lismore. It was quite an early one. It had an MVHR and everything, but it was quite draughty. That's an aside, but they are incredible the way they're put up. A really good method of construction.

JIMMY: I mean, they're kind of doing it here too. A lot of companies are doing that prefab building here as well. There's a company called Eden Insulation up in Cumbria who are really good.

LIAM: Yeah. I've worked with them on a village hall — quite a sizable village hall — and that was up in three days watertight. Mad, isn't it?

JIMMY: That is mental. I mean, you never see the amount of work that gets done in the factory. People go, oh my God, they've just built a house in three days. But it's just that you haven't seen the work that's gone into those panels being put in place. And the standard of workmanship you can get from that because it's factory conditions.

LIAM: Yes, exactly. It's the same model as a McDonald's in that sense — they just rinse and repeat. It's incredible when you've got something you can do that with. And for me, that's the way that we get to achieve any sort of energy efficiency targets. It's also at least part of how we achieve the number of houses that we want to get built. 

Setting up these factories and getting them delivered to site. You can set them up close to the raw materials as well.

JIMMY: Would that put a lot of the trades out of work though? Bricklayers and that sort of thing?

LIAM: Well, it's quite common for a timber frame to have a brick facade, so not necessarily. And the other aspect is that for every three people leaving the industry, only one person is coming in. In the next 10 years we're going to be hit with a crisis in construction where we don't have enough people for the work as it is. So we actually potentially need to be looking at alternatives. 

But setting up for prefab isn't going to be an overnight thing. These factories are massive and the costs are astronomical. Even the small factory I worked in briefly was employing five people full-time. So it's not nothing — it's invisible work. And the nice thing about that factory model is that by and large your workforce can be quite local. 

You're not marching trainees across the country to wherever the contracts have fallen.

JIMMY: Yes, that's true. I went to one factory workshop — I worked for Select, who's owned by Langro. They've got a factory workshop doing this prefab and it's pretty much all local people working there, which is great. Very impressive as well.

LIAM: Superb. And then your install teams can be local too. It would get to the point where your factories are local work and your install teams are local. It is a good way of going about construction. 

But even if we went absolutely mad for it now and the government subsidised everything, setting up the factories would still be 10 years off from being a major player in construction.

JIMMY: Cool. Like it. Next point. So what advice would you give to young tradespeople who want to move into high performance builds and retrofits such as PassivHaus?

LIAM: I would talk to places like the PassivHaus Trust, the AECB, and just try to get involved with people who are working in PassivHaus. The thing is, realistically, most of us working in PassivHaus at the moment aren't making loads of money. So it's going to be like internships. 

It's awful, but this is actually a case where the unpaid internship model works, because you're not going to have the knowledge to be able to pay your way. But I do know people who've worked with me and got paid something at the end of the day — you've done an amount of work, here's something for it. 

So gaining the knowledge in that way. It's difficult because there isn't an infrastructure for training people to get into more energy efficient construction. That infrastructure doesn't exist. We do need the government to weigh in on this. I've been trying to get involved in setting up training guidance for years. Friends of mine have tried to do that independently as well. 

There's the tradespeople course, which is a perfectly good course, but it's for foremen — there's nothing for people actually on site on the tools. At the moment, getting onto a PassivHaus site as a standard builder is the only way in. 

There isn't a formalised training route. It's a nod and a wink — they've worked on PassivHaus before, that's the way to go about it. I came into this as a labourer. 

It's been pure good fortune and people I've known. That's the only way for it at the moment. Just because it's PassivHaus, just because it's EnerPHit — the retrofit standard — it doesn't mean the people working in it want you to not know what you're on about. We need brickies. We need joiners. 

We need all of those people. The additional stuff to build to the standards we're talking about — it's dead easy. Honestly, it's really, really easy. I've often said that if I do my job right, I'll put myself out of a job. We've just got to get that thing to click.

JIMMY: Am I right in saying you're speaking with CITB?

LIAM: Yeah. I've been having conversations over a period of time. There are a few people I'm talking to at the moment and we've got some links through. We're hoping to get somewhere with that, but I don't know what that means yet. 

We've all been here before trying to set up a course, trying to get something to work. It's a difficult thing because how do you actually carry out that training? Like a rigid insulation board — you're teaching someone how to cut it between floor joists. 

You've got your jig set up, they've cut that bit of insulation. 

What are you going to do with it? It's going in a skip. It's really hard how we go about this. It needs to be on site. It needs to be whilst people are doing the work. And that's why I'm saying — if people want to get into PassivHaus, they need to just get onto a PassivHaus site and jump. 

There isn't something special that people are going to look for. If you are good at your trade, you will be good at PassivHaus. If you just want to make your price and then go to the pub, maybe it's not for you. But if you take care, if you take pride in your work — PassivHaus, retrofits, any description — you are the people that we need. 

And there are people who will train you.

JIMMY: Good stuff. I like it. Lastly, if you could change one thing about the construction industry tomorrow to improve building performance, what would it be?

LIAM: I would change the tendering processes. That's a major stumbling block at the start of it. A lot of larger building companies have been put off PassivHaus by being led down the garden path, losing a load of money, having their fingers burned and not wanting to do it anymore. 

And in some of those cases, the builder actually gained the knowledge and the experience, but what they walked away with was — I'm not doing that again. When actually they then had the ability to go and do it better next time. They had their fingers burned because the process isn't collaborative early on. 

People have a responsibility to make sure that everyone's going to get what they need out of it. If someone's coming on and doing something they don't have direct experience of — like a joiner who's also being asked to fit insulation — they know their joinery price, but if I look at what they've put in for the insulation and it seems a little cheap or a little expensive, you need to stress test that. 

How have you arrived at this price? Do you know how long this is going to take? That needs to be extrapolated out over the whole job. We need people to get trained. A lot of housing associations are going for PassivHaus now because it's a sensible thing to do. 

But we're still stuck in this mentality that we want jobs done cheap, stuck to a programme, stuck to a budget that isn't realistic. That's what needs to change. And they're wasting people's time with competitive tenders that are nowhere near viable.

JIMMY: Do you think the small company needs to be looked after more in the tender process? I go back to my cousin — he was going to do a load of piling, pricing it for one of the tier one companies. He's dyslexic and they sent him this package that was that thick. 

So he took it round to a mate of his who said, look, Rob, I wouldn't even get involved with it. Just walk away. All that is, they're tying you up any way they can with all sorts of clauses. Retentions, all of that. Just walk away. 

So in that respect, I think the little person needs to be looked after, particularly on payment as well, because they hold onto your money and you haven't got the cashflow to keep going.

LIAM: I often feel that it's sometimes in the larger builder's interest to make a smaller company fail. I'm not going to name names, but I've definitely been in situations or seen situations where it's in the main contractor's interest to let a smaller company fail. 

And that's wrong. But that's the perverse incentive we've got in this system. It's all about saving money, it's all about profit. I can sort of see the sick incentive to do that sort of thing. It's the elite mentality, isn't it? Basically psychopathic thinking for gains, not worrying about anybody else. 

I've worked for some magnificent large companies who are nothing like that. But they still exist.

JIMMY: Oh, absolutely. So that's pretty much it, man. How can people find you? What's your company name?

LIAM: So my company — I'm not very imaginative — it's LGS Airtightness, which is my initials and the word airtightness. That will change in future, hopefully, as I bring more people in to work alongside me. 

So yeah, LGS Airtightness. I'm constantly in the process of setting up a website — one day I'm sure I will — but at the moment it's just Liam Schofield on LinkedIn. You can find me on there. And hopefully at some point I'll actually get round to getting my brother-in-law to do me some branding and a website.

JIMMY: It will help, yeah. Good man. Well, thanks very much for the interview. Very insightful, very educational. I've thoroughly enjoyed this one.

LIAM: Thanks, mate. I've really enjoyed it too. Thank you for having me on. I'd love to go and have a beer with you at some point and put the world to rights.

JIMMY: Oh yeah. We just need to find the middle ground between Manchester and Essex.

LIAM: Cheshire and Essex — we'll sort it out.

JIMMY: Nice one. Top man. Enjoy the rest of your Sunday, mate.

LIAM: You too, mate. Thanks very much. All the best. Bye mate.