A system that helps keeps a basement or cellar free from water is better know as Basement tanking.

A basement tanking system will either be installed when the basement, cellar or similar building is being built or a different system is applied to a building when it is already established. Basement tanking is a term used in the dampproofing industry which basically means a waterproofing system designed to prevent water from gaining entrance into a basement or similar underground structure.

External basement tanking systems are more commonly used when the basement is first built. The main idea of them is to keep water away from the junctions where the walls and the floor meet, since this is a weak spot formed by a joint. There are various designs used when making an external tank, but most of them use a waterproof membrane that is basically wrapped around the concrete. It is installed before the cement is poured, and after the forms have been removed it is basically wrapped around the entire concrete section, effectively enclosing it inside of a tank. Drainage pipes are installed to protect the outer edges.from constant water. Surrounding the area with gravel helps to carry the water away from the cement and the membrane, rather than allowing the water to constantly beat against them.
Here at London Damp Specialists Ltd we are experts in all areas of damp and the avoidance of it. Get in touch with us today to discuss your requirements and let us visit your property or business to analyse the problem and come up with a suitable remedy. Call our experienced team today on Outer London 020 8528 3864 or Inner London 020 7458 4864.

A basement or cellar is a space of a building that is either completely below the ground level or partially below the ground, mainly for utility purposes such as:

  • Car parking
  • Wine storage
  • Storage of any materials
  • Heating system
  • Air conditioning system
  • Distribution purposes

There are many types of basements depending upon the location and utility.
Daylight basement is located on a slope, where part of the floor is above ground with a door to the outside. Part of the floor lower than the ground level is the true basement space and attached with ventilated windows to prevent damp problems. Look-out basement is constructed even on a flat area where the basement walls extend above the ground level with the windows above grade. Walk-up basement is one that has exterior entrance through a stairwell with basement doors to prevent rainwater from accumulating it. A finished fully underground cellar is a room below ground level in a house which is used for storing wine or coal. It has to remain at constant cooling with small forms of ventilation. Underground crawl space is a type of basement where one cannot stand upright but crawl on the soil below. It is mainly used for storage and rat-proofing purposes.

Basement of a building forms the foundation of the structure and it has to be constructed with utmost care and preventive measures. In warmer regions, basements are not built usually, but in colder regions, foundation must be below the frost line. Basement walls should have the surrounding earth backfilled around them to return the soil to grade. Putting up gravel and French drain is necessary to stop water from entering the basement at the bottom of the wall. Walls below grade must be sealed with water repellant coating. Concrete floor constructed must be facilitated with proper draining solutions. Small extractor fans and dehumidifiers can be fitted to dry out the condensation issues. Sump pump helps the best to draw out water rising in the basement and pouring outside the foundation area. Damp proofing materials can be applied to the basement walls and proper drainage systems enhance protection.
Basements become not the part but the foundation of houses. Skillful construction and maintenance play vital roles in longstanding productivity.

The pressure of water in the ground causes moisture to flow into your basement, cellar or service pit.

The foundation must be insulated as dampness located in the basement is a real threat to the building and immediate measures are advisory to prevent serious outcomes.


Make sure that there are no cracks and holes in the foundations, basement walls and floor.
Basement waterproofing is a technique that deals with the ways to prevent water from entering the basement of the building. Basement waterproofing is sealing the basement off the ground water with insulations, sealants, sump pumps and special drainage systems to ensure good utility space and foundation. Most typical causes for wet basement are condensation, run off and groundwater swelling.

Noticing dampness and mould growth indicates condensation problem leading to wetting the walls and floor of the basement. Usage of a dehumidifier for a considering period prevents basement wetting for a long time. Simply aerating the basement by opening the windows can provide the best preventive measure.


This is a rigid plastic unit with maintenance access ports. Runoff occurs due to melted snow and rain water running from the house due to hydrostatic pressure forcing water through gaps or cracks in walls. Preventing run off is made by making the outside ground to slope away from the building (at least one inch vertically for every 12 inches horizontally) and the downspouts are away from the foundation in leak-free condition. When runoff water travels through water, mould and algae appear as symptoms of dampness.

Groundwater swelling takes place when the water table exceeds the high point and causes wet basement with water bubbling up from the joints between the wall and floor. Expert advice is requested in this case. Mainly the grade of soil surrounding must encourage water to flow away from the foundation and not towards the house.


Water is collected from the floor channels and discharged into the sump chamber.
Water must be made to flow away from the foundation by forming slopes. Gutters and downspouts must be free from blocks and leaks and avoid pooling. Downspouts must discharge water 5 feet away from the foundation. Plants and gardens must not be close to the foundation as the decaying matter allows water to enter the cracks in the wall. Coating with water repellant paints on the wall, applying concrete sealers and insulating with waterproof membranes can reduce wet basement condition. Cracks in joints and walls must be repaired to prevent the entry of water with sealants and concrete. Allowing a sump pump while construction helps to draw water when the level rises higher than the limit and discharge it outside. French drain system can be introduced for serious water issues for a controlled draining system of ground water and runoff water and also installing hydro clay to fill the voids helps to prevent water seeping inside the foundation.



For sound masonry and longevity of the foundation, there are products on the market which act as water repellants and sealants preventing basement dampness. A cemented multi-coat render system has a high performance in resisting the water seepage through the cracked wall or joint. It is designed for applying on to appropriately framed background that is uneven and has high level of cracks. The render also has an adhesive coat that sticks to the cracks resulting in good texture and comes in a variety of colours. Cemented multi-coat render applied on the external wall acts as weather resistant repelling damp infestations and growth of moulds and algae. It is easy to apply as it is ready mixed and suitable for most types of brickwork or block work.

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