SmartVap 100 Internal Building Wrap 1500mm x 30m Roll - Residential Grade draught seal There maybe other cheaper products

There maybe other cheaper products on the market

With air coming from down low in a door

It can also be used to test the efficiency of duct sealants and to calculate duct performance overall

Here's why downlights are still a good option:

SmartVap 100 Internal Building Wrap 1500mm x 30m Roll - Residential Grade draught seal There maybe other cheaper productsProctorPassive SmartVap 100 An internal membrane which provides an air tight barrier for mainly residential buildings, when installed optimally Features: It is semi translucent, and is also light weight, to aid installation It is a double layer polyamide film that provides variable vapour diffusion resistance depending on the ambient humidity conditions to help prevent condensation, mould and timber rot occurring in ceilings, walls and floors. Comes