Is this damp, stormy weather causing you problems? Do you get dampness inside your house when driving rain lashes the outside of your walls?
Cavity wall insulation and damp
We’ve noticed that people have been complaining about damp problems (such as black mould, condensation, staining and damp internal walls) when cavity wall insulation has been installed. Examples are “I bought cavity wall insulation, so why is my house damp?” in the Daily Telegraph and “Will insulating my cavity walls cause damp” in YouGen.
When damp problems can occur
There are instances where damp problems can occur with cavity wall insulation. “Cavity wall insulation: damp problems” by Which describes some contributing factors. These may include:
- Where a property is exposed to high levels of wind-driven rain
- When a property is not sheltered by other buildings, trees or land formations
- Where external walls are in poor condition with cracks in the brickwork or defective pointing.
- When the cavity itself is poor, with bridging by rubble or by mortar clinging to the wall-ties.
How damp problems can occur
Penetrating damp, caused by wind-driven rain can soak the external brickwork. The cavity wall filling becomes damp and loses its insulating properties, especially so if it is loose-blown or fibre insulation that fills the cavity.
This may result in the signs of dampness being visible, such as stains, peeling wallpaper and mould. To complicate matters, the external brickwork can freeze when damp, leading to cracking and further degradation.
Masonry Protection with DryWall Thermotek
If your walls are filled with cavity insulation, then there is a solution! Drywall Thermotek
Thermotek does not block the pores of the masonry, it lines them with silanes and siloxanes that repel water, thus the masonry can still ‘breathe’.
One single-coat application of DryWall Thermotek repels penetrating damp, plus it provides significant thermal insulation as well by keeping the wall and insulation dry. For instance, in single-skin brickwork there is a measured energy saving of up to 29%. It is suitable for brick, stone and concrete.
Check out the Peter Cox Drywall Thermotek page, for more about this valuable wall treatment and to arrange a survey.