Air tightness testing of buildings

All owners of single-family homes - both those who already use homes and those who are just building them - have probably heard about the thermovision test. However, it is also important to test the air-tightness of buildings. What is it about?

Air tightness test of the building

Air tightness test of the building

A tight building is one where there is no free circulation of air between the inside and outside and vice versa. Each house should be built in this way, because the leaks in its housing carry a number of risks, both for the building itself and residents (eg in the rooms there is an unhealthy and harmful microclimate). A leaky building is also excessive heat loss in the winter months, and what is connected with this is the high home heating bills. To eliminate these unfavorable phenomena, a leak test should be performed. It also allows you to check the quality of work performed by construction and installation companies. In many European and Scandinavian countries, the performance of such a test (and removal of leaks) is a compulsory document for receiving the building.

What is the leak test?

The leak test allows precise localization of any cracks and spots of defects in the external structure of the building (indicates the places requiring repair) and checking the operation of ventilation - is it in accordance with the applicable standards. The test consists in forcing the pressure difference between the building and its surroundings by using a fan that pumps a specific air stream - the pressure difference is 50 Pa. This causes all air to leak into the interior. Leaks must be identified. For this purpose, you can use the "hand" method, that is, applying your hand to point and linear places. The smoke generator or anemometerturns out to be useful , which will register the flow rate in m3 / h.

Thanks to maintaining constant pressure, specialized software calculates the amount of infiltrated air. This allows you to determine the so-called the n50 coefficient. It informs you how much air you get into your home within an hour and how many times you can change air volumes within an hour. The maximum permissible n50 multiples are given in the relevant standards.After conducting tests in accordance with Polish standards, reports are provided describing the obtained results of the vases, paying attention to the observed defects.

When should the leak test be carried out?

Leakage test is best performed at the finishing stage of the house, after closing the building, i.e. when the external partitions are plastered, window and door joinery is installed, inside it is possible access to a sealed shell, for example in the attic there is a vapor barrier foil, and there is no layer finishing (eg plasterboard lining). All connections and installations that pierce the building envelope should also be installed. The leaks observed at this initial stage will be cheaper to repair than in a building already commissioned. The leak test can be carried out throughout the year. The measurement usually covers the entire heated surfaces of a building or its parts, and necessarily rooms with mechanical ventilation or air conditioning. It is good to do them again after completing all the work to verify the results.