It is mandatory for new dwellings in the UK to undergo building air tightness test in conformity with Part L1A and L2A or part F1 of The Building Regulations. Individual home builders or building companies must engage an accredited air testing company and the air tightness testing cost is to their account. The building must match air permeability rating and SAP calculations. Costs are not fixed since building type and size varies and cost also depends on other variables.
Representative cost of air tightness tests
Air tightness testing cost varies according to various factors. Typical costs you can expect to pay are given below.
- House with 2-4 bedrooms: The cost depends on the size, interior volume and other parameters and also the number of tests. One test can cost around £250. Two tests set you back by £375, three tests cost around £500 and four tests cost £600 or so.
- Larger homes: The starting price is £300 for one test, £450 for two tests, £550 for three tests and £700 for four tests.
- Flats: For flats the test costs are lower. Expect to pay £200 for one test, £250 for two tests, £300 for three tests and £375 or so for four tests.
The costs of such tests would be high for builders taking on residential development construction activity. However, there is relief in that if accredited construction details are used then only 1 of each dwelling type must undergo building air tightness test. There are other stipulations as well that builders can follow to reduce costs. If the builder constructs a building following the same design pattern in the preceding year had passed the test then the test may be waived. If you, as a home owner, add an extension and if it is below 1000 sq. mtrs area then the test is not mandatory.
Think of the benefits
- Commercial builders cannot avoid the building air tightness test and associated costs but one must consider the benefits for builders and for buyers of such properties:
- Leaks can result in about 40% losses. Leaks lead to higher energy consumption. When you switch on the air conditioner in summer then cold air will leak out and your air conditioner has to work harder and longer. In winter cold air enters the interiors and your heating system must consume more fuel to keep interiors heated to the required temperature. Both situations do not arise if air test is followed by remedial action to plug leaks and builders may be able to sell dwellings at a higher price.
- Individual home owners will find that the tightness tests reveal gaps that can then be sealed. The result is more comfort and reduced fuel bills. If not for savings in fuel cost then at least from the perspective of reducing impact on the environment one should have the air test carried out on their property. If your home is well insulated and sealed it can give you better returns should you ever wish to sell it in future.
The best way to reduce air tightness testing cost is for builders and individual home owners to consult air pressure testing service provider right at the planning stage. If that is not possible since construction may be complete or nearing completion then it is a good idea to adopt best practices to seal all possible areas where leaks can occur and then just have one test conducted.
