UK Building Regs Updates (Parts F, L, O & S) Webinar
Q&A and slides
Are all revisions applicable in England and Wales?
Yes, all revisions are applicable in England and Wales
Lighting calculations are required for apartments under Part L? Is there a criteria to be met?
Lighting efficacy (Lm/W) is entered within the SAP and SBEM modelling and can be altered – there are no specific targets, but a reduced efficiency will impact the overall SAP rating and emissions of the building. In general, somewhere in the region of 100 lm/W is what we would generally estimate in the initial stages.
What’s the (P/F)?
The P/F on the SBEM slides refers specifically to roofs (Pitched and Flat) with specific requirements for each within the non-domestic criteria.
What is the difference between the SBEM & SAP Assessments?
SAP (Standard Assessment Procedure) is the assessment method for Part L compliance applied to dwellings, with SBEM (Simplified Building Energy Model) the applicable modelling method for Buildings other than Dwellings.
Is the photographic evidence required on all projects? Including refurbishment, or just new and extension? Resi and non resi?
The photographic evidence requirements only applies to new build dwellings. Non-dwellings and extensions are exempt from this requirement.
With all the extra certification requirements, will this not just further reduce the number of homes built/completed per year?
There is a potential for this, but ultimately it is down to the industry to adapt and meet the requirements to ensure legal compliance. However, we are developing a system to assist clients in the collation and referencing of this information to oil the wheels as much as we can.
What about the costs on the end users to enter into a contract with the EVCP installer? This can be £2500 per annum.
The costs to the occupier are not mentioned specifically within the regulations, and if there is a contract to be signed up to then this should be clearly outlined to the resident within the legal documentation prior to contracts for rental or purchase.
In an ideal world the chargers would be installed by the developer as a standalone item, with no forward contract, with the resident able to benefit from the charging of their vehicle, only paying per unit of energy used.
On Part S, what happens if the number of associated parking spaces is less than the number of apartments?
In this specific instance, all spaces would need to have a EVCP provision. Where there are more spaces than dwellings, 1 per dwelling only applies.
Will the requirement to follow Part O (overhang, certain opening sizes and number of windows etc.) be given any consideration by the planners while trying to gain planning?
It is not necessarily in the interest of the planning officer to allow items external to the dwellings should this contradict other policies or be deemed to be visually detrimental. However, certain elements are needed to gain compliance.
Therefore, the issue of Part O compliance and Planning Compliance should be looked at separately. Any visual amendments would need to be cleared through planning and we strongly recommend that Compliance with part O Is looked at as soon as possible in the design process to ensure that any measures implemented form part of the application pack.
Under Part S is a replacement dwelling treated the same as a new build dwelling? i.e demolishing a single dwelling and erecting a new dwelling in its place?
Yes, this is deemed as a ‘new dwelling’ under Regulations, and therefore this policy applies.
Is there any allowance for brise soleil with the solar gain calcs?
Yes, this can be modelled within a dynamic model and will assist in the reduction of thermal gains. Internal blinds, surrounding buildings, and vegetation cannot be included within Part O modelling. For the simple assessments, horizontal shading should be included within high risk areas with a 50 degree cut off. Specific shading devices can only be accounted for within a dynamic assessment.
Can overheating be dealt with via mechanical ventilation in the case of not being able to account for natural ventilation?
Yes, this can be dealt with mechanically, however this is dependent on the orientation of the space, and also the use of the room which would impact the solution imposed. If you are looking to achieve compliance mechanically then this will need to be dynamically modelled to confirm. The use of mechanical extract can be implemented to reduce internal temperatures, however often, the volume of air needing to be moved can result in large, noisy fans being installed. In some cases the increasing of air flow via an existing ventilations system (MVHR for example) can allow marginal spaces to comply.
Why are A2A heat pumps so rarely installed in UK but so common in places like Scandinavia?
There is a nervousness on heating through air as this can cause issues around allergies and dust creation. In addition to a cultural bias towards warm panel heating in the UK. There is a limit to which you can heat air before the dust in the system is burned, causing smells and respiratory systems. Due to the relatively poor insulation performance of UK dwellings, the supply air temperature would have to be quite high, resulting in these issues persisting.
Who’s responsible for compiling the BREL report and who will assess the content?
Anyone can provide the BREL report. The SAP assessor will be responsible for reviewing the content and satisfying themselves that the appropriate documentation has been provided to enable an Energy Performance Certificate can be provided for the dwelling.
Do you see a requirement for attenuation on ventilation ducts?
The ventilation system (running at trickle ventilation speed) will need to meet the noise limits identified in the presentation. The need for attenuation on the ducts is dependent on a number of factors e.g. the duct layout, noise from outside coming in through the ducts, the fan selection and noise generated at the required fan duty, location of the ventilation unit. It may be possible to not provide attenuation but this would need to be considered on case by case basis/
In your experience when undertaking overheating assessments, if you don’t allow for windows to open at night does a dwelling overheat? How do you deal with this?
Yes typically if you are unable to purge heat through openable windows at night time then the dwelling may overheat. This can be dealt with by providing an alternative attenuated air path into the dwelling, running the MVHR system at elevated ventilation rates or even adding a cooling pack to the MVHR system to condition before being supplied into the bedroom and living room.
Have you found that electric vehicle charging provisions can result in network upgrades?
No not necessarily. We’ve certainly seen a need for network upgrades as a result of a combination of the need to switch from gas heated dwellings to electric heat pump heated dwellings. This combined with the need for EVC provision has increased the maximum electrical demand resulting in network upgrades, which may not have been required if heat pumps/EVC were not required.
Is Part L compliance affected If mechanical cooling is used to pass Part O?
Yes, as the SAP assessment must reflect that mechanical cooling is installed within the building. If mechanical cooling is provided, changes may be needed to ensure that the building complies with the standard energy efficiency requirements of Building Regulations Part L .
The requirements of background ventilators to meet part F. What are the options for these?
These can be in the form of air bricks, trickle vents or some sort of acoustic treated terminal. Minimum free areas are prescribed in Part F.
Do I need to inform the DNO when I install an Electric Vehicle charging point?
Electricity networks do require access to technical information for the EVC point including; capacity, power quality data, in order to assess individual applications for suitability to connect to the network. Useful guidance can be found in the following link: Connecting electric vehicles and heat pumps to the networks – Energy Networks Association (ENA)
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