Wednesday, 9 May 2012

Damp Problems and Advice

Given the current unseasonal rainfall, "this building is damp" may be the most common complaint regarding properties at the moment.
Are there damp ‘tide marks’ on your interior or exterior walls?
Are there signs of condensation on your walls and windows?
Is water escaping from roofs and gutters?
Is there mould on your walls, ceilings or around your windows?

If so, then you need to take action to prevent the dampness and obviate further problems such as peeling of wallpaper and paint, dry rot, wet rot, some kinds of woodworm, timber and structural damage, and health concerns. Some of these issues are very serious and can propagate through your property if left untreated.
See our web page for more about damp problems

Rising Damp

The classic form of ‘rising damp’ consists of moisture from the ground rising in through the wall by capillary action. Typical signs are the 'tide marks' of damp staining, often up to abouta metre above local external ground levels. Damp staining and visual damage can be seen indoors as well.
A solution is to insert a physical damp course in walls above ground level. Peter Cox recommends the DryWall Silane Diffusion method. This can be used for internal and external walls of any type and thickness, both brick and stone, including 280mm cavity brick walls.
Given the current level of rainfall and the high water table, external land drain installations to lower moisture levels in the ground can be very effective in certain instances.
See our web page for more about rising damp treatment.

Basement waterproofing

With the water table so high, dampness can enter basements, cellars, service pits and some ground-floor rooms where the floor is below ground level. Dampness comes in through the walls and floor due to water pressure from outside.
A Cavity Drainage Membrane is used for basement waterproofing. The interior walls and floor remain dry, while water is channelled into a drainage system, often using a sump and pump. As an alternatively, ‘tanking’ is the traditional solution for basement waterproofing, with a Cementitious Multi-Coat Render.
For more, see our basement waterproofing page

Penetrating Damp

Penetrating damp can also result when there is high rainfall, particularly with strong winds as well. Roofs, walls, windows, doors, chimneys, need to be in good order. Gutters, down pipes & drains should be clear, with no obstructions, leaks or overflows. The dampness and damage may be more localized if there is for instance a defective gutter that is overflowing
 It is important to diagnose the problem under the severe weather conditions and put in place a remedy. Otherwise the damage caused by long term damp can require more repair than the damp problem itself.

Internal damp

Water escaping from a water pipe, waste pipe, washing machine or the central heating system can cause damp patches to appear. Technically a leak rather than damp, these usually result in a very wet area close to (but not necessarily directly under) the source.
Condensation can cause damp problems resulting from poor ventilation, poorly heated rooms and too much moisture being produced by for instance showers, tumble dryers and cookers.
Cold surfaces and poorly ventilated areas are vulnerable to dampness and mould growth, for instance in cupboards, corners, behind heavy furniture and on cold outside walls. 
There’s more on our website regarding damp proofing

Damp Proofing Survey

A Peter Cox damp proofing survey report will evaluate your property and will inform you if and when early action is required. We will advise which damp proofing solutions are needed, based on:
  • Cost-effective treatments
  • Minimised risks
  • On-time installations
  • Future-proof solutions