Cavity walls are designed to prevent water from penetrating the internal walls of your home
Cavity walls are designed to prevent water from penetrating the internal walls of your home. The air space between the inner and outer walls allows any water that does get in to drain down to the footings. However, for this to work the cavity must be completely clear. If the cavity is not clear it can't function as intended.
The results of a blocked cavity wall are moisture being trapped and bridged from the outer and inner wall resulting in internal damp. From experience, this process is usually helped along by a previous poor cement repoint or old and missing mortar to the outer skin brickwork. You could also add high ground levels and a lack of functioning air bricks and many other factors to this but this page is about cleaning cavities.
Cavity wall cleaning may sound dramatic but actually it's a lot simpler and easier than it sounds. More importantly, it's a lot less costly than some modern magic damp proofing.
How a cavity wall may be blocked
The cavity may become blocked because:
- It was not cleared correctly when the house was constructed
- Old lime internal mortar has come away and built up over time
- Debris has got in during building repairs or modifications
- You have a nice tree that has grown into the wall...
- Insulation has dropped below DPC
All the above can form a bridge that carries moisture across to the interior of the house, which in time will cause penetrating damp and mould.
Cavity wall cleaning and clearing process
- We carefully remove bricks to gain good access to the cavity.
- A camera is inserted in the cavity and used to inspect the condition.
- If required the cavity will be cleared 150mm below the DPC
- The cavity will be cleared by means of a dust extractor and manual removal.
- Once cleared the bricks will be carefully replaced and finished with the appropriate mortar.
- We responsibly dispose of the removed matter.