Damp proof membrane for walls

damp proof membrane for wallsApplying a damp proof membrane for walls can be an excellent solution for damp problems in the home. A damp proofing membrane has several advantages. Firstly, it is a relatively cheap and easy process to install one – DIY kits are widely available and you certainly don’t need to consider yourself a DIY expert to attempt the work yourself. Secondly, damp proof membranes are suitable solutions for a variety of cases of damp (more of that later). And, thirdly, damp proof membranes offer long lasting protection against damp, particularly issues such as condensation and black mould spots.

What are the main uses for a damp proof membrane?

Damp proof membranes are best suited for properties that have just had a new damp proof course inserted. In virtually all cases of damp (except where structural damage has occurred), remedial treatment such as a new DPC will be sufficient. However, because of the effects of damp, surfaces may have deteriorated. This is where a damp proof membrane for walls really comes into its own, as it can provide a key for that deteriorating surface.

Damp proof membranes are also useful to isolate already damp walls or those contaminated with salt.

What is a damp proof membrane and how do they work?

Damp proof wall membranes are essentially a plastic sheet. Different materials are used depending on the intended application, the extent of the damp and the finish that is required on the wall – always seek advice about what might be the most appropriate membrane to use.

The thickness of a damp proof membrane is typically 0.5mm to 1mm with stud sizes ranging from 1mm to as much as 8mm. Some membranes use a dry lining system as a finish. Others have a mesh welded in to allow for rendering and plastering after application.

The cavity, or air gap, that a damp proofing membrane has creates up to 10 litres of space in between the membrane and the wall.

A damp proof membrane for walls has a long life expectancy (typically over 30 years) and is very strong and flexible too. As they can compensate for any structural movement over time, they provide longevity and peace of mind.

The membrane provides a physical barrier between the existing damp wall and the new finish. It also prevents any vapour and moisture, along with salts and contaminants, from impacting on the internal finish of the wall. They significantly prolong the life of the new internal finish.

Is a damp proof membrane the solution?

Certainly, if used in conjunction with a new damp proof course, a damp proof membrane can be an excellent solution. This is because it adds an extra (and long lasting) protection from damp which is a fantastic way of treating surfaces that have been damaged by damp.

Applying a damp proof membrane to an internal wall is also cost-effective and as they can be installed with very little, if any, surface preparation, it’s no surprise that it is a popular solution.

For DIY enthusiasts, it’s a project that most will feel confident enough to take on. The installation really only requires cutting the membrane to the correct size, placing it to the wall and neatly folding the membrane around the corners.

Then all that is required is drilling and fixing the membrane to ensure a tight fit and applying the wall finish to the membrane.

Of course, if the membrane isn’t of the appropriate type or thickness and isn’t applied with a well-fitting and tight fit, then you run the risk of it failing. Therefore, it’s never a bad idea to seek, at the very least, professional advice if you are considering the solution of a damp proof membrane for walls.


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