All Property Repair cellar and basement conversion work is backed by a waterproof membrane guarantee. With Property Repair you can be sure your cellar conversion or basement conversion is fully guaranteed.
Instead of using precious building land around your home, losing valuable outdoor space and incurring high building costs, long delays and a lot of construction mess, why not make use of your cellar? Create the space you require and increase the value and investment of your home by undertaking a basement conversion or cellar conversion.
With rising house prices and the current economic climate basement and cellar conversions are more popular than ever. When undertaken correctly with a specialist cellar conversion company a basement conversion can add significant value to your home.
Sourcing specialist materials, textures, fixtures and fittings, providing detailed architectural drawings, dealing with all the relevant authorities for planning permissions and building regulations, right down to the finishing touches – Property Repair can help you create the rooms you want and the space you need.
Waterproofing Effectively Cellar & Basement Conversions
Even if you do not intend to carry out a full conversion to your cellar, waterproofing it will still add value to your home, providing a useful storage area and giving future buyers the option of turning it into another room if they wish.
Being below ground, the earth surrounding the cellar acts as a route for water to enter through the walls, and in order to prevent this from happening, the walls must be fully waterproofed. There are several ways in which to do this, either by sealing the walls using a surface coating, known as wet basement tanking, or through the use of membrane systems.
The way these systems work is by applying a waterproof coating directly to the inside of the porous cellar walls to prevent moisture from seeping in. They do not remove the water, they simply create a barrier.
For a tanking system to work well, the walls that the tanking product – these range from cementitious coatings, bituminous coatings, membranes, paints and sealants – is being applied to must provide a good ‘key’ (i.e. a scratch coat). Tanking systems also require the brickwork of the house to be stable due to the fact that tanked walls need to resist water pressure that will build up. In older homes, preparing walls to take whatever coating is being used can be quite time-consuming, involving hacking off old plaster, raking out old mortar, repointing and applying salt-neutralising products.
Waterproof coatings can be applied using a trowel or are sometimes sprayed on, with the aim of forming a bond with the masonry substrate, to create a completely waterproof barrier. Plaster can then be applied on top of these coatings.
Attention must also be applied to weak points in the structure – typically the wall/floor junction – where water is most likely to enter.
Cavity Drain Membrane Systems
Membrane systems are used on most cellar conversions, particularly in areas with high water tables and on older properties, as they do not rely on sound substrates for their effectiveness.
The majority of these systems involve studded membranes, often made from high-density polyethylene, being fixed to the walls with plastic plugs, fitted with mastic seals behind the head. Water is allowed to flow down within the cavity created to the floor – which will also be covered with a membrane – and into a drainage system.
The floor can be covered with screed, or a layer of insulation and chipboard. The stud profile also means an air gap is created, acting as a depressurisation zone for any water that comes in through the walls, so that as the water enters, under great pressure, it loses its force and falls behind the membrane, down to a drainage conduit, which channels water out, often with the assistance of a pump. This can then be covered with plasterboard. The floor can be sealed with either a membrane and concrete, or a studded membrane, but you should seek professional advice regarding which will be best in your area.
Inevitably all this will add to the floor height of the cellar, reducing headroom. Unless the remaining headroom is not lower than that used for new, modern homes – around 2.35m – a dig out and underpinning of the walls will be required before any waterproofing work can begin.