Rising Damp Problems?

What is rising damp?

Rising damp (often called "salt-damp" or just damp) starts at the bottom of walls where water enters the internal wall from below. It is cause by moisture rising in the wall due to problems with the damp proof course which is a layer of waterproof material in the wall of a building near the ground used to prevent rising damp. Generally speaking it is moisture which rises up from the subfloor and damages masonry (brick and concrete) walls. Rising damp is also often a cause of moisture entering the living area of a home. The salts in the (efflorescence) moisture will cause deterioration to mortar and also to masonry bricks.

Whilst this can take place over a long period of time, it is always best to treat all rising damp issues before they become a problem.The excessive moisture which is causing the rising damp problems will be caused by either a lack of ventilation or a water leak or water intrusion into the subfloor due to a flood or storm.

Horizontal damp/penetrating damp

Horizontal damp is often mistaken as rising damp, but it causes the same type of damage to a building. Horizontal damp is moisture which impacts upon a building horizontally as opposed to coming from below. Typically, garden beds butting directly onto brick work are a major source of horizontal damp as the moisture from the garden bed will migrate to the brick work and penetrate into the building envelope, causing damage to floors, and walls, render and plaster.

Solutions to Rising Damp

Whilst a damp course will provide a barrier between the damp generally found in the subfloor from the rest of the building, it will not actually dry out the damp subfloor which is causing the damp problem.It is preferable to attempt to dry the subfloor first and therefore eliminate the excessive moisture which has caused the rising damp issues to occur.

Subfloor drying remediates rising damp

• If the subfloor is excessively wet due to a water leak, storm or flood, then it will require professional equipment to dry it out in the short term. If left alone, some subfloors will NEVER dry, or take years.
• We have had experience of returning to flooded properties several years after a flood, to find the subfloor still damp and still causing damage to the building envelope.
• We operate high end drying equipment which will quickly and efficiently dry any subfloor. Once subfloor is dried, ventilation must then be installed as moisture will continue to wick up to the surface for quite a while, depending on the severity of the flooding.

Subfloor ventilation and rising damp

• In the subfloor, the moisture present in the soil will cause long term moisture issues if it is unable to escape from the subfloor via passive vents. In sold brick houses, often just passive vents are not enough to prevent moisture issues and forced air ventilation systems are required. But the more passive vents the better. Forced air ventilation is guaranteed to dry out the subfloor and involves operating fans in the subfloor which draw the moist air form the subfloor and expel it externally.
• The better and more expensive subfloor ventilation systems also use fans to introduce fresh air into the subfloor, creating a vortex of fresh air in and stale air out. Dampco only installs this type of subfloor ventilation system - with fans inputting air and others expelling air.

Damp course treatment for permanent rising damp solutions

• This places a barrier between the source of the damp and the building, preventing rising damp from entering the building envelope and damaging the rendered walls. The dampcourse solution is injected into the lowest mortar course and, once it dries, creates an impenetrable barrier If the dwelling is double brick, the dampcourse needs to be injected into both sides of the wall in the affected areas.

Call us on 1300 382 826 or email us for more details or to arrange for a free inspection and a report on mould removal and treatment options.