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Damp Proofing With Chemical Injection

brick wall If you discover that damp has got into your brick work you could imagine that it will cost a fortune to fix. Generally what it means is that for some reason your damp course has failed and you have a case of rising damp. This might sound scary, but new methods have made this a job which can even be completed by a good DIYer.

Rising damp generally comes from ground water which rises up through any permeable wall structure. The water is literally sucked up the wall by the masonry which acts as a wick. The water could rise as much as 1.5 metres unless something is in the way to prevent this.

This is where your damp course comes in. Unfortunately some homes were built without damp courses or they will have deteriorated over the years. In other cases the surrounding ground has risen or the house has subsided, meaning that the damp course is now too low.

If this has happened to you and the water has seeped inside your home you will need to first remove all the contaminated plaster and wood and then treat the problem on the outside wall. Chemical injection damp proofing is the ideal way to retrospectively apply a damp proof course.

Holes are drilled into the mortar joint at around 150mm above the ground level and to a depth of up to 20mm. There is usually one hole between each brick or around 4 -5 inches apart. It is also a good idea to drill holes from the inside of the property as well.

The silicone emulsion cream or liquid is injected into the mortar to control the rising damp with the use of a high pressure pump. You will notice that the colour of the bricks changes as they become filled with the solution. This will indicate when your holes are filled. The holes are then filled with mortar or plastic plugs. If you want to try this for yourself you will need to hire the correct pump for the job.

The cream reverts to a liquid once it has been injected and spreads out through the mortar and into the masonry. After 2 to 6 weeks the cream starts to cure and will provide a damp proof course. After this time you can complete your redecoration inside as the wall will need the chance to dry out completely.

It is important to realise that this is a long and messy job, but still possible to be done by a DIYer. You just need to take care to cover your furnishings and use protective gear to protect your face and hands from the chemicals.