DELTA® cellar products reliably safeguard outer and inner walls from moisture penetration.

Basement protection

A cellar has many functions, no matter whether it is used as living space, serves to store personal articles, or accommodates important domestic equipment, such as the central heating system. At the same time, it has to meet numerous requirements. These include, on the one hand, the load imposed on it by the other floors that are built on it and the lateral pressure of the soil. On the other hand, there are diverse challenges of natural origin, such as an entire range of water-related impacts like surface or façade water in case of heavy rain, fissure water, impounded water, and groundwater. To ward off all these factors, the cellar needs to be waterproofed, or it will be threatened by water damage, mould, or faults in the static of the building. Therefore, foundation protection is a subject of central importance for house owners as well as builders. Made by Dörken, the DELTA® cellar products reliably safeguard outer and inner walls from moisture penetration.

Damp in the cellar

Damp in the cellar – this is not a rare problem. A slightly mouldy smell, dilapidated plaster, or even mould infestation – these are typical signs. In the long run, inadequate cellar protection will cause elementary harm to the foundation walls.

Water finds many ways into masonry. It even migrates into concrete. Damp rising from the foundation hampers the use of cellars and may even reach the ground-floor apartment. The consequences include mould infestation and mould spores in the interior air. These are dangerous to health and trigger a multitude of diseases and allergies. Moreover, damp walls charge the air with water, making the interior climate unhealthy. The presence of water in the walls damages various functional layers, such as interior and exterior plastering and of course the heat insulation. Next to possible damage to the masonry, this causes considerable energy losses. Moreover, subsequent repairs to the cellar masonry may be extremely complex and very costly.

This list of possible consequences shows that cellar protection pays. DELTA® foundation protection, drainage, and waterproofing systems provide comprehensive and sustainable protection for your cellar rooms.

What does cellar protection consist of?zoom

What does cellar protection consist of?

There are many ways of protecting a cellar. While acute problems, such as leaks or mould infestations, do require rapid action, cellar protection may also be planned ahead as part of a cellar conversion or construction. After all, a functional cellar that is comprehensively protected does increase the residential and market value of the entire building. But what would you need to comprehensively safeguard your home against damp? The most important aspects of cellar protection will be described below.

Drying a cellar

A dry cellar is the basic prerequisite for any construction or rehabilitation measure. Even though a damp cellar wall may not always call attention to itself by visible spots or bad smells there still may be moisture in the walls. Therefore, it is advisable to consult an expert on the condition of the cellar walls. If damp or moisture is discovered, the message is: fight causes, do not treat superficialities.

But how can it become necessary to dry out a cellar in the first place? Cellars are wholly or at least partially surrounded by soil, which is moist at least. For this reason, cellars and/or subgrade building elements should at least be protected from soil moisture. Depending on the condition of the ground, it may be necessary to provide higher-quality waterproofing – possibly reinforced by a continuous drainage system – to ward off groundwater or accumulated seepage water. Information on the condition of the soil may be obtained from a building-ground expert. If, for instance, fissure water is discovered in the building ground, this may lead to water pressing laterally into the outer cellar wall. In such cases, expertly planned waterproofing together with a continuous drainage system that envelops the entire cellar will provide protection from leaks. However, older buildings especially do not have such waterproofing. Thus, many do not have horizontal barriers (damp-proof courses) in their walls, which may lead to moisture problems caused by capillary rising damp. Others again have a coat of tar or bitumen as their only waterproofing. This kind of waterproofing is no longer state of the art these days as cellar rooms are increasingly frequently used for residential purposes, so that dampness in the cellar is no longer acceptable. Further damp-related problems may be caused by condensation moisture in laundry rooms, for example, by leaky pipes, or by external influences such as driving rain.

Keller trockenlegen: Trockene Wand statt nasser Schwamm

Waterproofing a cellar

Kellerabdichtung mit DELTA®-THENEzoom

The waterproofing is the most important component of cellar protection. No building should be without it, and it should always meet the individual requirements of the surrounding elements. Therefore, it is necessary to investigate even in the planning stage what the construction of the cellar should be like. If it is to be placed on a foundation slab of normal reinforced concrete with walls built on top of it, all soil-boundary surfaces must be waterproofed to withstand the local water action. Where pressing water or groundwater is present, a so-called black tank may be used. This normally consists of a multi-layered bituminous waterproofing that entirely covers the cellar as well as the foundation slab. Alternatively, a so-called white tank may be envisaged, in which case the cellar will be made entirely of waterproof concrete. Next to a special concrete mix, the reinforcement requires particular attention in this case, for it should ensure that the width of the cracks caused by the shrinkage of the concrete remains within admissible minimum limits. Joints between elements and/or between walls and the foundation slab are sealed by tapes in the concrete. Where conditions like soil humidity or seepage water prevail, conventional waterproofing will be sufficient, consisting of the waterproofing of the foundation slab, cross-sectional waterproofing (horizontal barriers or damp-proof courses) in the walls, and waterproofing on the outer walls of the cellar. In this way, the waterproofing of a cellar determines its construction.


Cellar rehabilitation

When a cellar is built from scratch, all options to protect it are available. Integrating the waterproofing methods described above in its planning is no problem. Where older houses are concerned or, at worst, moisture damage is already apparent, refurbishing the cellar is in order. This may take various forms: if the masonry is to be rehabilitated, the protection of the foundation may be effectively enhanced by installing a DELTA® damp-proof course. When a cellar is to be converted, special requirements apply, such as heat insulation. To make cellar rooms habitable and usable, they need to be heat-insulated as well as waterproofed, in which case a perimeter insulation appears indicated.

Keller sanierenzoom

Products for cellar protection

The cellar products of the DELTA® brand represent flexible system solutions for foundation protection and drainage. We use top-quality material only; witness the service life and functionality of our products. Thus, for example, the DELTA®-SOFTFLEXX damp-proof course is convincing because of its unusual elasticity, which is why it is used in many varieties of masonry. Separating the subsoil from the foundation walls, the DELTA®-MS sub-base course keeps groundwater from rising up. The DELTA®-TERRAXX protection and drainage system is a genuine classic. It serves to protect the cellar waterproofing, which is why no cellar should be without it. 

Moreover, DELTA®-GEO DRAIN QUATTRO and DELTA®-TERRAXX have a certified service life of 100 years!

Dörken GmbH & Co. KG

Dörken GmbH & Co. KG
Wetterstraße 58
D-58313 Herdecke

Tel          +49 23 30/63-0
Fax         +49 23 30/63-355

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