Damp Proofing Service - Bedford

Help and Advice

Making a cellar usable:If you have an older house with a cellar, the likelihood is that it will be a damp and musty place fit only for the storage of some old tins of paint. Anything left in an untreated cellar is likely to become mouldy and unusable fairly quickly.

Because cellar walls are below ground, moisture held in the earth which abuts your cellar walls will find its way through the walls causing continual damp in the cellar, and because their will always be damp in the earth, the problem will never go away. The damp will also make the room feel permanently cold and will probably deposit mineral salts and mould all over the walls, making it impossible to decorate effectively.

Unless the house was built with a cavity drainage system, the most cost effective way of making the cellar a usable space is by Tanking, the application of a fluid waterproof slurry ( blend of cement and chemical additives) to both the walls and floors of the room. The slurry dries to create a waterproof barrier, preventing the ingress of moisture and leaving a dry surface, ready to decorate.

Before tanking can begin, the walls and floors of the cellar will need preparation to ensure the best possible result. This will include removal of existing plaster and paint n order to expose the underlying brickwork. Any loose masonry or mortar would need to be rectified and the walls and floors cleaned to ensure that any dust and debris is removed.

The tanking slurry will normally be mixed on site, and two coats applied. Once the application is complete, walls can (and should) be rendered and a floor screed applied to make the space more habitable and to protect the tanking layer. Re-rendering can normally be done within a day or two of tanking.

Preventing Condensation:You will tend to notice condensation more in the colder weather. The reason it occurs is because warm air is able to retain a higher proportion of moisture than cold air, so when your daily activities such as cooking, ironing, and even breathing produce moisture, it just becomes suspended in the air. When that warm air meets a colder surface (such as a window pane), the air cools and can no longer hold the same level of moisture, so it deposits it on the cold surface.

We've provided a few ideas on how to avoid condensation where possible

Clothes Drying

Try not to dry clothes in your home. If this is not practical, keep the door of the room where clothes are drying closed. Open the windows, as this will allow the moisture from the clothes to escape outside and will prevent it circulating around your home. – If you use a tumble drier make sure it is vented to the outside or use a condensing dryer.

If possible, try to dry damp clothes outside of the house. If you have to dry them inside, make sure that you open the windows to help vent the moist air. If you use a tumble drier, it should either be a condensing model which extracts the moisture into a tank for disposal, or its hose should be vented to the outside of the home

Rising Damp: Generally a result of ground water leeching up through the wall or floor. To prevent this becoming a major problem, a damp-proofing membrane is usually specified when a house is first built. Over the years, however, this can break down causing tell-tale signs. You’ll probably spot peeling wallpaper near your skirting boards, signs of rotting in the skirting boards themselves and crystalline deposits on the walls.

A common cause which can be fairly easily rectified is where you’ve allowed the level of the ground outside the house to rise above the damp course of your brickwork. Perhaps you’ve heaped soil against an outside wall inadvertently; this will allow Ingres to moisture and cause rising damp problems.

Generally, however, the problem will be a breakdown in the damp proofing and it is likely to persist and get worse over time, so if you see the signs, you should call a local damp proofing specialist as soon as possible.

Wet Rot: Wet rot is not particularly uncommon and will tend to be found in the timber older buildings. It is a less serious problem than dry rot and normally easier to rectify. Wet rot is caused by the fungus coniophora puteana which infects damp wood causing decay.

If you live in an older house, check around the window frames by applying a little pressure with your thumb. If you can feel the wood gives and feels a little spongy, it’s likely that you have wet rot. Often, you can find wood with a perfectly normal looking surface that looks quite sound (particularly if painted) but which has rotted underneath.

Wood will not normally rot without some external influence and it is quite likely that if you find some wet rot, it will be due to some structural defect that has developed causing water to collect on the wood without allowing it to dry out, and thereby attracting the fungus.

The first thing you should do is to identify the source of the water ingress and rectify the problem, possible sources to investigate include loose roof tiles, blocked or leaking guttering, cracked bricks or missing mortar or damaged damp proof course.

Having fixed the source of the problem you will find that the rotten wood can be cut out and replaced by a skilled carpenter, or of course you would have the option of replacing the wood in its entirety. If the timber is structural, for example a joist, it should not be repaired, it should be replaced by a new pre-treated timber.

Penetrating Damp: Penetrating damp is quite a common problem in homes. Symptoms include:

• Plaster detaching from walls
• Water stains appearing on masonry.
• Damp patches on interior walls
• Stale, Fusty smells
• Growth of black mould/mildew

Penetrating damp, which is the ingress of moisture through the wall is something that affects many buildings. Penetrating damp can often lead to other damp retention issues and to damage to the fabric of your home. Penetrating Damp is often caused by:

• Brickwork being porous
• Defective pointing
• Leaking guttering and downpipes
• Defective joints around doors and windows

When it rains, or water runs off onto the brickwork, the moisture can soak into the masonry but generally evaporates before reaching interior walls. Where there are abnormally high levels of moisture, usually caused by one of the problems mentioned, the moisture is unable to evaporate quickly enough to prevent water ingress through to the inner wall. This is where you begin to see the symptoms listed above. If you think you may have problem, call Beds Blast Cleaning straight away

Damp Proof Membranes A look at the options

The Wall Surfaces

There are many options available for helping to eradicate damp on the walls. Damp proof membranes are one such option as they can be installed on most wall surfaces. Membranes act as an impermeable layer, separating the damp brickwork from any inner surface. Often meshed, they can generally be plastered over to give a new, damp protected inside surface.

Damp Courses

Failure of an existing damp course is often the root cause of damp problems, and in some older properties, a damp course may never have even been installed. Installation or replacement of a physical damp course, or of a chemical dpc is a major job and requires specialist advice to determine which solution will work most effectively given the construction of your houses