1. LEVEL 4 Air Pressure Testing
Air Pressure Testing: ADL2A & ATTMA TS1

2. LEVEL 4 Air Pressure Testing
We are going to look at:
What it’s about
Why it matters
The Regulations
Where it can go wrong
The consequences of failure
Recommended approaches
The next set of slides we are going to cover the lists see above, then read each one. 2

3. LEVEL 4 Air Pressure Testing
What is it about?
Part L2A relates to ‘Work in New Buildings, other than Dwellings’
Substantial reductions on CO2 emissions must be achieved (and proven), compared to an identical ‘Notional Building’ that would have just complied with the 2002 version of Part L.
SBEM can be used a concept design stage to calculate the relative CO2 savings achieved by measures such as:
Improving U-values (e.g. through more insulation)
Improving HVAC & lighting efficiency
Reducing cold bridging and/or solar gain
Using ‘renewable’, and …..
Reducing air-leakage
Whether or not improved air-tightness is used as a ‘compliance tactic’ it must not exceed 10m3 of air leakage, per m2 of envelope, per hour at 50 Pascal's differential pressure.
The Key Requirement is to prove a reduction of CO2 emissions….
This slide gives us the reasons to undertake this action which as been around since 2002 Building regulations, read the slide 3

4. LEVEL 4 Air Pressure Testing
Why it matters ?
It contributes to UK’s CO2 Reduction Target (Kyoto), by causing buildings to be more energy efficient.
Enables right-sizing of HVAC Plant, and…
Reduced Energy Costs (for Heating & Cooling)
Protection of Building ‘Fabric’ by reducing Interstitial Condensation
More Comfort for Occupants (Improved Productivity)
Continue to read the slide but also add where necessary 4

5. LEVEL 4 Air Pressure Testing
The consequence of failure?
Air leakage accounts for a significant proportion of the overall energy losses in UK buildings.
In leaky buildings it can occur constantly, driven by wind, internal/external pressure differences and the ‘stack effect’.
Buildings don’t need to breathe, only people do!
Therefore….
“Build Tight – Ventilate Right!”
Again read the slide 5

6. LEVEL 4 Air Pressure Testing
Where it can go wrong?
Eaves details
Voids/cavities left open to interior
Voids above solid ceilings
Gaps between steel frame and inner-leaf masonry
Service penetrations
Unsealed dry-lining
Windows, doors, weather seals
Unsealed layers in built-up roof systems
Risers & plant rooms
Hollow floor planks
Leaky HVAC systems
Permeable materials
This diagram shows where leakage does occur and where builders can get things wrong. Go through each one 6

7. LEVEL 4 Air Pressure Testing
Where improved Air-tightness is not being used as a compliance tactic, the building must still be proven to meet the following minimum standard.… The rate of air leakage through the building envelope must not exceed 10m3 of air, per square-meter of Envelope, per hour at 50 Pascal's differential pressure (between inside & outside the building).
This regulation is for buildings constructed from 2002 to 2006, In 2006 onwards a default of 15 can be used. I believe it’s a step backwards when we see Europe on 5 and Sweden on 3. 7

8. LEVEL 4 Air Pressure Testing
The ‘Envelope’ is the “shell” of the building that contains the “conditioned air”. In most cases this would comprise the ground floor slab, the perimeter walls and the underside of the roof.
If the roof-void is naturally ventilated then the top floor ceiling becomes the top part of the envelope
Read the slide to indicated what constitutes an envelope 8

9. LEVEL 4 Air Pressure Testing
The regulation in ADL2A and ADL2B:
All buildings, with over 500m2 gross floor area, must be air-tightness tested to prove they do not leak air at a rate more than the target air-permeability rate required by the design (which must be no more than 10
Buildings with a gross floor area below 500m2 don’t necessarily have to be tested, but if they aren’t, an penalising ‘result’ of ’15’ has to be used for the SBEM calculations!
Extensions to existing buildings, have to be tested if they are over 100m2 and more than 25% of the existing total floor area.
Read the slide 9

10. LEVEL 4 Air Pressure Testing
Recommendation approach?
Reduced Air-Leakage can help with overall compliance
A lower ‘air-permeability’ figure (than the maximum of ‘10’) will count further towards the overall CO2 emissions savings required, as calculated by SBEM.
It can offset the cost of other carbon-reducing measures, such as using ‘renewable’ or more efficient services.
However, if a lower air-leakage rate is specified, it has to be ‘designed and built-in’, then proven by testing.
Currently, roughly half of the larger, more complex buildings tested fail to achieve the minimum Part L standard of ’10’ at the 1st attempt, despite it having been a requirement for the last 4 years! 10

11. LEVEL 4 Air Pressure Testing
This shows the size of the units we use and all our equipment are tested against a static certificated fan system which is checked annually by BSI. Thes units will provide around 30 c.m/sec () 11

12. LEVEL 4 Air Pressure Testing
This shows some of our small door units providing the pressure to undertake the test 12

13. LEVEL 4 Air Pressure Testing
Reasonable Pressure test Target Setting.
If When conducting the SBEM calculation on new builds, if the pressure test result is set too low and becomes unachievable.
Your final result will fail your EPC
So Please remember, (read the slide first) if your initial figure is too low than you will have to use the test results and re-calculate which could mean failure of your EPC. 13

14. LEVEL 4 Air Pressure Testing
ANY QUESTIONS OR FEEDBACK
Any questions or clarity needed over this topic and slides
I have a very short video of a leaky building. 14