Rising damp is considered one of the most controversial types of damp nowadays. In case you have a problem with rising damp, then you are in the right place. This article will tell you what rising damp is, how you can get rid of it, and other interesting information.
It is a significantly rare form of damp affecting the walls of buildings. Rising damp is caused by the moisture from the ground that eventually travels up through walls by the capillary action, which means that groundwater gets sucked up through the tiny tubes in bricks, such as a series of straws. The water contains salts that can travel up through a wall. Around an affected wall, you may notice other porous building materials like plasterwork as well as timber found in floorboards, skirtings, and joists. All these materials easily absorb groundwater and you can find evidence of wet rot in timber.
In most cases, rising damp is noticed by the water damage it usually causes to the internal walls of the building. It could be something like a damaged sewer pipe or missing mortar on the outer wall. Paint and plaster deteriorate and the wallpaper loosens. Then the visible stain also appears on a wall in the tide mark’s form at a point where groundwater has reached. Chances are high that you’ll also see salts blooming on an internal surface, which is something usually associated with a rising damp, leading to a debonding of plasterwork and paint. Externally, mortar or exterior wall coatings may crumble as well, followed by white salt stains, which may also appear on walls.
Causes Of Rising Damp
The majority of buildings have a form of barrier installed at a lower level of a wall for preventing water from rising up in that way. It’s called the damp proof course or DPC, which is made of water-resistant, non-absorbent materials like bitumen, plastic, and slate, depending on the period property was built. At times, these physical DPCs fail over time. In fact, in older houses, they often don’t exist at all. In case you don’t have the DPC or there’s evidence suggesting that it has failed, there’s nothing you can do to prevent water from travelling up the wall. In other cases, the DPC may remain intact, but it may be bridged. This is exactly where damp from the ground starts travelling up past a DPC because of the construction fault.
Some examples of this include:
- External or internal plasters/renders overlapping a DPC.
- Debris in a wall cavity or the subfloor void.
- External ground levels raised above a DPC.
- Solid floors.
- Inappropriate insulation material in a cavity.
- Intersecting masonry structures or abutting garden walls.
Signs Of Rising Damp
The following signs are some of the most common ones of the rising damp you need to look out for:
- Dark patches on the walls, which are damp to touch. However, to fully make sure that it’s actually a rising damp, first try determining that the brickwork/masonry is really wet and not just wallpaper or plaster.
- Tide marks of salts.
- Mould with a musty and damp smell.
- Discoloration and fragmenting plaster.
- Staining of the wall coverings, blistering paint, and peeling wallpaper.
- Decaying timber e.g. floorboards, floor joists, skirting boards.
Rising Damp Treatment
You can treat rising damp by using damp proofing injection cream. It is considered both an economical and effective way of treating it. You can choose between individual cartridges or complete kits of cream from a variety of brands. Once you choose the cream, all you need to do is inject, or hand-pump it into the specially-positioned holes in a mortar course. After it’s inserted, a damp proofing cream then reverts to the liquid, allowing it to penetrate bricks while achieving complete absorption.
Once it cures, it creates the powerful water-repellent barrier as well as a new chemical DPC, which can prevent water from rising up a wall. Alternatively, you can consider installing a new damp proof membrane so that it can act as the damp proof course. However, this can be much bigger as well as more complicated since it involves both installing the physical damp proof membrane as well as taking out every brick along a failed mortar course.
As you can see, rising damp can be quite a hassle to deal with, especially if you don’t take care of it in time. Fortunately, there are efficient methods you can use to get rid of it. All you should do now is choose the method you prefer to solve the issue.