Basement Tanking

Basement Waterproofing London Properties

Many London homes have below-ground living space and due to the underlying clay layer called the Thames Valley Basin, the ground holds moisture, making damp a real threat to basements and cellars across London. The UK has a damp climate with above average rainfall and this is the perfect environment for damp, mould and timber rot to thrive.

Various Types of Basements

The different types of basements include:

• Full Basement – This refers to a full underground space that covers the entire footprint of the house, which is common in London properties.
• Partial Basement – A basement that only covers a portion of the house footprint, which is popular in Victorian terraced houses.
• Walkout Basement – Typically built on a slope, a walkout basement would have at least one window that is above ground and a door that allows direct access to the outside.
• Walkup Basement – There are steps that leads down to a door at ground level, which is common in terraced homes.
• Daylight Basement – Also built on sloping ground, a daylight basement has one side fully above ground level.
• Traditional Cellar – Typically a dark space that is used to store wine or other items and this space would require ventilation.

Regardless of the basement style, we can offer a free assessment and a written quotation for damp-proofing work.

What is Basement Tanking?

Basement tanking is a term that refers to a specific waterproofing method that is very popular with London homeowners. Before work can commence, the basement must be emptied of furniture and other items, then all damaged plaster is removed from the walls and ceilings; the substrate is carefully prepared and waterproof render is liberally applied and left to fully dry. Special waterproof plasterboard is fixed to the ceilings and all joints taped, then a waterproof plaster is applied and a second coat is applied to all surfaces, followed by a skim pf plaster. Then the surfaces are ready to be wallpapered or painted. The floor is also waterproofed and the project is completed and after a couple of days, furniture can be returned and the space is ready for occupation.

Cavity Drainage System

This is a very effective alternative to basement tanking and it is suitable for area where moisture levels are high. Much like basement tanking, the underground space must be cleared of everything and all damaged plaster and other materials must be removed. Channels must be created on the floor with a sump area and a pump to send water to drainage points. Studded membrane is then carefully fitted to walls and ceilings, which creates a cavity that allows water to run down and into the channels in the floor, where is ends up in the sump area and it is then pumped to the drainage points.

Common Issues in London Basements

Below ground living space can be impacted by any of the following:

• Rising Damp – The most common problem in London basements and cellars; moisture can easily impact the walls and ceilings. Damp can rise from the floor and cause damage to plastered walls and a professional evaluation is advised.
• Condensation – Droplets of water can form on the walls if excess moisture is present, especially with no ventilation and this causes serious damage to plaster and timber. Before repairing the damp damage, it is essential to identify the source of the moisture and carry out damp-proofing work.
• Penetrating Damp – Moisture can enter a basement through the walls, which would cause damp patches that do not dry out. If dampness is severe, a damp-proofing professional would recommend installing a cavity drainage system.
• Woodworm – Dark and damp spaces are ideal breeding grounds for two species of beetle, namely, the Deathwatch Beetle and the Common Furniture Beetle. Tell-tale signs include rows of tiny holes in timber with small mounds of dust nearby, along with creamy white eggs in the nearby vicinity.
• Timber Rot – Both wet and dry rot can cause serious damage to a basement/cellar and we recommend a professional approach to eradicating the insects.

If you would like a free evaluation of your basement, contact London Damp Proofing and one of our PCA-certified damp surveyors would arrange to inspect the property and provide you with a detailed written report the following day.