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
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.
