In passive house design and construction we have 2 main measurements.

First one is the differential pressure measurement (also called as the Blower-Door Test) (EVS-EN 13829:2001) (modified version of ISO 9972:1996, Determination of air permeability of buildings).

Differential pressure measurement is the measurement of the resulting air flow rates over a range of indoor-outdoor static pressure differences. It can be performed during the construction or after the construction has been done. However, performing the tests during the construction gives us more reliable results.

However, it’s better to use the fan pressurization method for diagnostic purposes and then measure the actual infiltration rate with tracer gas methods (a single tracer gas measurement will give limited information on the performance of ventilarion and infiltration of buildings)

The Equipments used :

–          air-moving equipment : used to induce a specific range of positive and negative pressure differences across the building envelope.

–          Pressure-measuring device : with an accuracy of ±2 Pa in the range of 0 to 60 Pa.

–          air flow rate measuring system : device to measure air flow rate within ± 7 % of the reading.

–          temperature measuring device : with an accuracy of  ± 1 K

The differential pressure measurement test result directly affects the specific annual heat demand, thus influencing the combined uncertainty for the specific annual heat demand. (The aim of my master’s thesis is to be able to add a worksheet into PHPP, where we can calculate all the uncertainties,thus the Passive House institute can put this uncertainty value into their certificates, both for the passive house components, and to passive houses)

The second measurement is the thermographic Analysis (currently ThermaCAM B4 infrared camera is in use by Passive House OÜ, calibrated by  FLIR Systems AB, Sweden). As the differential pressure tests, the thermography can be performed during and after the construction. However, it is mostly used when inspecting the building, to detect the possible leaks.

Thermography is not a decision point in building inspection. It just gives us an idea where we might have & have problems. These suspicions must be verified by other methods, such as moisture meters, humidity&temperature datalogging, tracer gas testing, etc.

A few illustrations on thermographic analysis in passive houses :