With any existing or new build, airtightness is crucial to prevent unnecessary energy and heat loss. A Blower Door Test can can be used to check if the construction of your home or building can measure what the leakage rate is. Whilst not compolsary it is recomended that blower door testing be carried out on all buildings as it gives important insight into the quality of the build. When constructing a new home or building, the best time to undertake a Blower Door Test is after it has insulated but before the plasterboard is installed. If leaks are found, they can be easier to fix at that point.