Summary: Learn how to deal with rising damp, what to do if you find rising damp, how to fit a damp-proof membrane, replace a damp-proof course, inject the silicone-based compound and seal the interior wall.
Damp patches on floors and around the bottom of walls could indicate a problem with rising damp. Other indicators of this problem include mould and peeling wallpaper. If you suspect rising damp, you could engage the services of a professional surveyor to determine the precise cause. Alternatively, you can use a damp meter to check the moisture level of the walls. These instruments are widely used in the building industry and provide accurate readings.
Concrete floors should be built with an integral damp-proof membrane (DPM), while walls should have a damp-proof course (DPC) between layers of brick near ground level. These are impervious layers built into walls and under floors that act as a barrier to moisture.
If the damp-proof course or damp-proof membrane have become damaged you will need to install new ones.
You can lay a new DPM over the concrete floor and construct a floating timber floor on top.
The layers required for laying a DPM over a concrete floor with a floating timber floor on top.
Firstly, ensure there is nothing against the exterior of the wall such as a flowerbed, garden refuse or building materials, allowing moisture to soak into the wall above the damp-proof course.
If this is not the case, you will have to install a new damp-proof course by injecting a waterproof silicone-based compound into the wall to form an impervious layer. This can be done from just the outside of the wall or from both sides. Some products work very effectively being injected only into the external wall, but always check with the manufacturer's instructions or your supplier that this is the case.
Drill holes in the mortar course at least 150mm above ground level.
With the damp problem now fixed outside, you should seal your walls from the inside.
Author: C J Mills Google+
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