FAQ

Why do we have condensation in our houses?

Daily household activities (cooking, washing and drying laundry, and taking showers) produce large amounts of moisture in a house. An average family produces about 5 litres of moisture per day. Modern houses have sealed windows, insulated walls and no open chimneys which means that more moisture is trapped in the property resulting in damp problems with damp. The Holland Damp Proof System® can ventilate your walls and help remove this moisture.

Does double glazing cure condensation?
No, condensation occurs in the coldest points of the house. In a double glazed property walls are often cooler than the windows so condensation is attracted to the walls.

Does a dehumidifier cure condensation?
Dehumidifiers can reduce the humidity level in a room by blowing air over a cold coil which causes the moisture to condense. This condensation is then collected in a container. There are a number of issues with using dehumidifiers which make them only suitable as a temporary measure:

• They are costly to buy and run.

• They only work well in well heated rooms.

• They need to be emptied frequently.

• They can be noisy and take up floor space.

Do special mould paints cure condensation?
Special damp or mould paints are often only a temporary measure. These paints and coatings use biocide which is composed of toxic chemicals. Mould cannot grow in this toxic environment but the damp problem still remains and it will re-appear when the chemicals stop working. This can happen in days or months, depending on the type of chemicals used.

Does rising damp exist?
Cases of pure rising damp are rare. Many people have a chemical damp proof course installed in cases where it is not proven that rising damp was the problem. If you are not sure if your property suffers from rising damp, the Holland Damp Proof System® is a great solution because it works on all types of damp.

What is the difference between airbricks and the Holland Damp Proof System®?
Air bricks are simply holes in the wall. They usually go straight through the wall and let air in and out of the building.

Drawbacks of airbricks:
• They can be drafty and cause heat loss in the property.

• They can let insects and mice into the house.

• They are often blocked off by tenants .

• Black mould can start to grow around them in cases of condensation.

The Holland Damp Proof System® is completely different from an air brick. As it does not go through the wall, it has none of the disadvantages of airbricks. All the airflow happens within the system which is fitted within the walls. There are no ventilation holes and there is no loss in temperature in the house, but the moisture is still removed. In fact, once the system has dried out the wall, it will become a better insulator and this should make the house warmer, which could result in reduced heating bills.

Will the Holland Damp Proof System® make my house colder?
No. The house will feel warmer and you could end up with reduced heating bills for 2 reasons:
1. When walls dry they become better insulators.

2. When humidity levels in the air fall, less energy is required to heat the house (see scientific research below by Professor Richard Mollier from Dresden).

The relationship between RH (relative humidity), temperature and energy necessary to heat 1m3 of air. At a temperature of 20°C (= 68°F) and a RH of 80% 50 K joule is needed At a temperature of 20°C and a RH of 55% 40K joule is needed A saving of 10K Joule which is 20%.

Will insects nest in the hollow Holland damp proof bricks and come into the house?
There is no risk of insects getting into the house since the bricks do not go through the walls. Insects will not nest in the system since there is a constant flow of air through them.

Why can the Holland Damp Proof System® lower my heating bills?
Since the Holland Damp Proof System® dries out the walls, they become better insulators, keeping the heat inside the house. By lowering the humidity level of the air in the house, you will feel more comfortable at a lower temperature, which leads to lower heating costs. Less energy is required to warm air with a lower humidity level. (See also: Will the Holland Damp Proof System® make my house colder?).

Does the Holland Damp Proof System® need fitting on several levels in my house.
No, there is usually no need to fit the Holland Damp Proof System® on any other level than just above the ground floor level. Less than one in every thousand houses we treat has our system at a level other than the ground floor.

Does the Holland Damp Proof System® need to be installed all the way round my house?
Our trained surveyors can decide whether the whole or just part of a house can be treated with our system. It depends on the type of building and the type of damp problems within it.

Why is Holland Damp Proofing UK Ltd not a member of the Property Care Association (formerly the British Wood Preserving and Damp Proofing Association)?
The above organization is a trade and lobby organization for the chemical damp proofing industry and therefore does not represent Holland Damp Proofing UK Ltd, which offers an eco friendly and chemical free product.