Episode 44:
Hello and Welcome to the Part3 with me podcast,
The show that helps part 3 students jump start into their careers as qualified architects and also to provide refresher episodes for practicing architects. I am your host Maria Skoutari and this week I will be giving an overview of the changes during 2022 running through of the changes in legislation and introduction of new ones.
So I wanted to create an episode covering the key changes that occur in the construction industry in 2022 now that we are officially into 2023.
The changes that occurred were with the Building Regulations that came into force in June 2022, the introduction of the Building Safety Act and the discussion around the introduction of the Future Homes and Buildings Standard estimated to come into force on 2025.
So what changes have occurred to the Building Regulations and to which Approved Documents:
The Approved Documents that have been updated and came into force in June 2022 were Parts L (Conservation of fuel and power) & F (Ventilation) with the introduction of the new Part O (Overheating) and Part S (Infrastructure for charging electric vehicles).
The key reason these documents have been updated and new ones were introduced is to assist the industry into achieving the UK’s carbon reductions target to net-zero by 2050 by cutting carbon for all new homes by 30% and 27% for other other buildings including shops and offices. The changes will also be used as a stepping stone towards the Future Homes and Buildings Standard to come into force in 2025.
So lets start with Approved Document F updates:
First looking at the updated for non-domestic buildings:
Under the new updates to Part F for non-domestic buildings, new guidance includes standards on minimising the ingress of external pollutants and the proper installation of ventilation systems and new guidance on performance-based ventilation standards will allow designers to assess ventilation strategies against individual volatile organic compounds, based on data from Public Health England, as an alternative route to using a total VOC limit.
The new updates recommend that all replacement windows in non-domestic buildings are fitted with background trickle ventilators unless it can be shown that replacement windows would not reduce useful ventilation or that a mechanical ventilation system is present. If outside noise is an issue, attenuating background ventilators are proposed to be fitted. New guidance also recommends that mechanically ventilated common spaces in offices have a minimum air supply rate of 0.5 l/s.m2, which is below the 1 l/s.m2 outlined in the government’s proposals.
A new requirement was also introduced in Part F regarding transmission of infection via aerosols by installing CO2 monitors in offices and specifically in ‘high risk’ rooms where there may be a risk of airborne infection.
Following the implications and issues highlighted from Covid-19, the guidance on recirculating systems was also updated stating that systems should be capable of operating in a mode that prevents the recirculation of air within spaces or between different spaces, rooms or zones within offices, unless suitable filtering or cleaning systems are in place.
Now looking at the updates for domestic buildings:
The Part F updates for domestic buildings introduces a new requirement that when energy efficiency work is done in buildings, the ventilation is not to be made any worse, in line with existing measures for controlled services and fittings.
A mandated checklist proposed is intended to make it easier for renovators to understand the impact of historic and potential future work to a building and whether the ventilation provision will be sufficient.
Ventilation guidelines will include a recommendation that replacement windows are fitted with a background trickle ventilator, unless it can be proven that the ventilation was not made worse.
To support homeowners, Part F now recommends that all installations of mechanical extract ventilation and installations of new background ventilators come with guidance on why ventilation is important for the health of buildings and their occupants. And a commissioning sheet and checklist, including design flow rates and maintenance requirements, should also be provided when ventilation systems are installed.
Moving on to the Approved Document L updates:
First looking at the updated for non-domestic buildings:
Under the Part L updates, non-domestic buildings will be require to achieve an average of 27% reduction in carbon emissions in relation to the 2013 standards. The governments position was that this mandate would achieve a balance between progressing towards the Future Homes and Buildings Standard and providing the industry with the time it needs to develop the supply chains and skills that will be necessary to meet the 2050 targets.
Another item Part L introduced is a new principal performance metric in measuring energy efficiency. Known as the ‘Primary energy’ to be used in combination with CO2 metrics to assess compliance with Part L, the Primary energy calculations take into account factors such as the efficiency of the building’s heating system; power station efficiency for electricity; and energy used to produce fuel and deliver it to the building. This approach, however, was faced with criticism from respondents and users that disagreed with using primary energy as the main performance metric to which the government responded that they will review the approach before implementing it into the full Future Buildings Standard.
Under the updates, new minimum efficiency standards were introduced for both new and replacement thermal elements, windows and doors. For example, the U-value of new walls under the new Part L(2) is 0.26W/m2 K, compared to 0.35W/m2 K previously and most types of new window, roof lights and curtain walling must achieve a U value of 1.6, versus 2.2 previously.
In terms of building services in new non-domestic buildings, the minimum efficacy of lighting installations has been increased to 95 luminaire lumens per circuit watt for general lighting and 80 luminaire lumens per circuit watt for display lighting. Lower efficacies in some rooms can be offset by higher efficacies in others and a separate standard for lighting that requires a high level of optical control, including innovative high excitation purity lighting, has been introduced.
The updates now also require that new non-domestic buildings require a building automation and control system if they include a heating or air-conditioning system of 180kW or over, rather than 290kW originally proposed. So new and replacement heating systems in both domestic and non-domestic buildings have introduced a new minimum standard to ensure that wet space heating systems in new buildings are designed to operate with a maximum flow temperature of 55°C. And finally, the new updates stipulate that all space heating and domestic hot water boiler installations in existing non-domestic buildings must now include new controls to improve the effective efficiency of the system. The minimum standards for air distribution, comfort cooling systems and lighting will also apply in existing non-domestic buildings. BACs must also have a maximum flow temperature of 55°C.
And Part L adopts CIBSE’s TM23 as the single approved methodology for testing airtightness for non-domestic buildings to avoid 'practical difficulties' of using multiple testing methodologies.
Now looking at the updates for domestic buildings:
New updates to fabric efficiency standards for new domestic buildings set the new U-values for new walls as 0.18W/m2k from 0.28W/m2 K and 1.4W/m2K or Window Energy Rating Band B for windows and roof lights from 1.6W/m2K or Window Energy Rating Band C. And U-values for doors have been updated to 1.4 from 1.8. However, fire doors are permitted to meet a U-value of 1.8 W/m2K in line with the previous standards.
The government has adopted a 'full fabric specification' for setting the level of the Fabric Energy Efficiency Standard (FEES) in new homes under Part L. Extensions to existing properties are now required to adhere to the SAP method of compliance for metrics of fabric energy efficiency and primary energy. According to the government, this will ensure that 'direct electric heating systems are not used in unsuitable circumstances resulting in high bills for householders.
And finally, additional updates were specified in relation to building services, where wet-space heating systems in existing domestic buildings must be designed to operate with a maximum flow temperature of 55°C, same as with non-domestic buildings, this was previously 75°C.
So that covers the updates to the existing Approved Documents, now lets look at the new documents introduced in 2022, starting with Approve Document O covering Standards for overheating in new residential buildings
So the new Approve Document O aims to ensure that new residential buildings, including homes, care homes, student accommodation and children’s homes are designed to reduce overheating with the rise in temperatures that we have been experiencing due to climate change. In terms of requirements and suitability in terms of location, it splits England into areas of 'moderate risk' and 'high risk' of overheating, the latter including urban and some suburban parts of London.
The regulation adopts a 'simplified' route, which is essentially a method of calculating overheating, which estimates compliance based on minimising solar gain and removing excess heat, so it sets standards based on whether the house or residential unit is cross-ventilated, its orientation and introduces a standard for the maximum amount of glazing allowed in a single room.
The alternative method in calculation overheating is through use of ‘Dynamic thermal analysis’ methods of overheating risk in homes allowing a more sophisticated analysis of buildings as an alternative route to compliance over the simplified method.
Guidance within the document includes acceptable strategies for limiting unwanted solar gain in the summer through shading and other means. Internal blinds or tree cover must not factor into a dynamic thermal assessment because they can subsequently be removed.
The measures proposed within Part O ensure overheating strategies are safe and usable by occupants, taking into account noise and pollution near the home, as well as the safety and usability of the windows and security, which may affect occupant behaviour. Information on overheating strategies must be passed to the building owner in the form of a Home User Guide.
And then we have the new Approved Document S:
Which requires all domestic new builds to have systems in place for the future installation for electric vehicle charging points.
The initial response and view from the industry on these changes are that the proposed uplifts are not high enough to enable significant reduction in carbon emissions in new buildings and the proposed measuring methods are confusing and not resolved and clear enough. Hopefully these concern will be met with the proposed 2025 Future Homes and Building Standard which has technical consultations lined up in 2023 and will introduce significant changes to make buildings net-zero carbon.
So that covers the changes to the Building Regulations, now let's briefly look at the new Building Safety Act.
This Act was introduced following the Grenfell Tower Fire tragedy in 2017 and the recommendations made by Dame Judith Hackitts Independent Review of Building Regulations and Fire Safety to prevent any such incidents from occurring in the future. It includes significant changes to building safety legislation for over 40 years and will make a clearer route of accountability for those who design, construct and manage higher risk buildings and how certain structures will be built, maintained and made safer. It will impact contractors, developers and organisations involved in the construction and design of in-scope buildings — defined as “higher-risk buildings” in England that are:
The act will also be introducing two new roles, the New Building Safety Regulator which will be a new body overseen by the Health and Safety Executive and will be responsible for enforcing more stringent regulations on safety and performance on high-rise buildings in securing the safety of the people in and around buildings and improving building standards.
And the second will be the Accountable Person(s) for residential high-rise buildings which can be landlords, freeholders who own or have responsibility for the building. If the building has more than one accountable person, the one responsible for the structure and exterior of the building will be the principal accountable person. And they will be expected to prevent building safety risks and reducing the seriousness of an incident, their duties will involve registering an existing building with the Building Safety Regulator which can be done between April 2023 and October 2023 and they must also register all new buildings before occupation. The Principal Accountable Person will be expected to prepare a Safety Case Report for the building, give safety case report to the Building Safety Regulator and apply for a building assessment certificate when directed by the Building Safety Regulator.
The government will also be able to restrict the ability of irresponsible developers to build new homes and the act will enable building owners to take legal action against developers, contractors and manufacturers for poor construction and defective products that have caused homes to be inhabitable in the past 30 years. And leaseholders living in buildings of more than 11 metres or at least five storeys will be legally protected from building safety costs.
In terms of The Building Safety Act and the architecture profession, it provides the ARB with further powers to regulate architects’ competence by ensuring they have the necessary skills, knowledge, experience and behaviours (SKEB) to perform their services. The ARB in turn released the Competency Guidelines for Fire and Life Safety Design that were published in March and comprise of 16 core competencies expected of architects. The Act will also include amendments to the Architects Act 1997 to enable the ARB to impose tougher sanctions on those who fail to meet the updated criteria.
The RIBA has also made its own changes requiring its UK chartered members, from 2023 onwards, to demonstrate an understanding of seven core areas including fire safety, design risk management and personal safety in order to renew their RIBA membership.
The Act will also impose further statutory obligations on architects under the new duty holder regime proposed for the lifecycle of higher-risk buildings. It implements Dame Judith Hackitt’s recommendation to replicate the existing titles assigned to duty holders under the Construction (Design & Management) Regulations 2015 (CDM 2015) to achieve what she described as ‘consistency and clarity across all regulatory requirements, to avoid unnecessary confusion’.
There will therefore be some changes and new responsibilities for the principal designer role:
The PD role is envisioned to be required to enforce a ‘robust ownership of accountability’ for the responsibility of managing design. Under the Building a Safer Future Consultation, writing about the PD HRRB (principal designer on a high-risk residential building) the MHCLG stated: ‘The PD HRRB should be part of the role of the lead designer, who will often be an architect but should always be the designer with the most appropriate professional background for the project.’ Thus imposing additional requirements on the Principal Designer which most likely be the architect.
The enhanced competency requirements could potentially be seen as a positive declaration of quality and professionalism for architects when compared against other designers. The RIBA has endorsed this position and stated that: ‘An architect is the best person to fulfil the principal designer role. When the Building Safety Bill becomes law, architects should rise to the challenge of increased responsibility’.
But in the post-Grenfell climate, which has seen architects’ Professional Indemnity Insurance (PII) premiums increase by as much as 300% over the last three years, it is not clear whether there is much uptake within the profession for taking on the significant liabilities associated with the principal designer role. Many architects have found that they are unable to obtain PII cover for issues relating to fire safety and increasingly seek to exclude this area of design liability from their appointments.
Previous consultations have suggested the principal designer’s duties will include obligations to: plan, monitor and manage the design at the pre-construction phase and co-ordinate all matters relating to building safety with designers and the client making sure it complies with the Building Regulations; they must then satisfy themselves that those involved in supporting the principal designer are competent and have appropriate organisational capability; and to take reasonable steps to ensure that designers are discharging their statutory duties and promoting the statutory objective. It would seem that for larger more complex projects a multi-disciplinary team will be required to take on these duties with at least a thorough knowledge of all Building Regulations, including fire safety requirements and potentially on smaller project it will be a role undertaken by a sole practitioner or a small company.
Fundamental questions remain
These are items yet to be fully determined and there remain fundamental questions concerning how these duties could be performed in practice and what the actual implication for architects will be in terms of responsibility, knowledge and insurance.
We can potentially expect that the standard appointment documents will have to be amended, that the Design and Build procurement route will have some changes imposed from these changes and PII insurers will need to consider whether they will offer related insurance cover and that those wanting to provide the new PD service will have to train & recruit staff as well as develop their management processes and on-going training programmes to meet the new requirements. The anticipated introduction of the new PD role is expected later in 2023.