Self Builders! Are you embarking on your first build? Confused by all these SAP calculations and air tests? Have no fear, BE is here with the essential checklist.
The regs are ever changing – whether it’s your very first experience of building regulations or perhaps you just haven’t built anything for a few years, you’ll need some key items for your building control officer (BCO).
These satisfy Part L requirements and need to be carried out by an accredited assessor (or ‘DOCEA’ – Domestic On Construction Energy Assessor). The process is split into two stages.
The design assessment must take place before anything is built, and ensures that what you intend to build will actually meet the energy regs or any local planning related energy policies. You will receive some reporting, which you hand to your BCO before you put a shovel in the ground.
The ‘As-Built’ assessment makes some checks on the finished product and results in some more reporting, including an EPC (energy performance certificate). You will save a lot of hassle, time and money by using the same assessor for both stages so make sure they are qualified to do both. The assessor does not need to visit site.
This is a test carried out towards the very end of the build and checks for gaps and cracks in the fabric of the building, which can contribute to heat loss. An engineer will visit your property and spend 1-2 hours fiddling with door frames, tubes and a big fan. The test itself will usually involve depressurise the dwelling (sucking air out) although for a Passivhouse test, both depressurising and pressurising are required.
You will be trying to reach a target set by your SAP Assessor (see above) and is a pass or fail procedure. Again you will receive a certificate which needs to reach your BCO.
You are very likely to be asked for calculations to demonstrate how you will meet the water use targets set by Part G of the building regs. This is currently 125 litres per person per day and is worked out by calculating the effect of different fittings, assumed uses and water saving technologies.
Much like SAP assessment, you need to provide a design stage report, then an as-built report.
Part F of the building regulations requires you to carry out testing to demonstrate that your ventilation system is working as it should. This applies whether you have very basic bathroom and kitchen extracts or sophisticated MVHR systems.
However – for whatever reason, BCO’s do not always request these….so whilst they are mandatory, we can’t promise you will be asked for them. We suspect that building control are generally taking a proactive stance and that if they suspect ill fitting ductwork or an inadequate system has been installed, they may well ask for the report.
5. Sound Testing (only if flats or adjoining properties)
Part E requires sound insulation testing to be carried out for flats or if there are adjoining properties.
An engineer will come to site and carry out a range of tests depending on the configuration of buildings. The tests provide performance data under both impact and airborne tests. Floors and walls will be tested on completion of the build and a report will be issued. This does rely on being able to access the neighbouring properties and again it is a pass or fail process.
So there you have it – you can either find consultants and contractors to provide all of these services, or you may find some really helpful folks who will wrap it all up in one package and take care of things for you!