RISING DAMP

Tell-Tale Signs of Rising Damp

When we inspect a building looking for damp, mould and timber rot, the signs of rising damp include the following:

• Crumbling masonry and brickwork – Moisture can compromise brickwork, masonry and mortar, breaking it down, causing the material to crumble to the touch.
• Moss growth on external walls – Vegetation growing on external walls is a sure sign that moisture is present, so do keep an eye out for moss and other fauna.
• Peeling wallpaper – Moisture causes the adhesive on wallpaper to lose its properties and if you see the corners start to peel away from the wall, this is a sign that excessive moisture is present.
• Bubbling paint – Emulsion paint bubbles when it meets moisture or it might become flaky and this is a visible sign that something is wrong.
• Bubbles in plaster – If a wall is damp, it can impact the plaster, causing air bubbles to form and this is an ideal environment for mould to form.
• Blown plaster – When a wall becomes damp, the plaster can crack and split, which is a sign that damp is rising from the ground, damaging internal walls.
• Mould & mildew growth – A moist atmosphere is ideal for mould and mildew to form, which is a health hazard. Prolonged exposure to mould can lead to serious respiratory conditions that may require hospitalisation. Dark corners are prone to mould growth, especially in a still, damp environment.
• Musky odour in the house – Damp leads to mould and that is usually accompanied by a strange musky smell in the house, which is quite evident.

If you notice any of the above signs, do not hesitate to contact London Damp Specialists on 020 8242 9391 or complete the online form on this website and we will be in touch in good time.

What Causes Rising Damp?

London sits on the Thames Valley, which is a clay-based region that has serious drainage issues and this means the ground holds moisture. Every building should have a damp proof course, or DPC, which is installed between brickwork courses near the ground level; the DPC is typically a thick strip of bitumen that acts as a barrier to prevent moisture crossing, thus keeping the building dry.

Compromised DPC Membrane

Ground movement can tear the DPC membrane, rendering the barrier ineffective, while time can also lead to the degradation of the DPC strip and the damage might not be immediately evident. By the time you realise damp is present, considerable damage could already be caused, which is why you should have the property professionally surveyed, which would reveal any damp, mould or timber rot issues.

Flooding

In the event the water level is higher than the DPC, the building will be affected and that will cause serious damage in a very short time. Water is drawn up by capillary action, impacting masonry, mortar, render and timber; the longer the period that the water level is high, the more damage will be the result.

Adjoining Properties

There are many terraced houses in London and because they are connected, a compromised DPC can impact the entire row of houses. If we survey a property and we find that the damp is coming from another house, we recommend that the customer contact the owner of the compromised house to inform them of the rising damp issue. Even building a low retaining wall can lead to rising damp if the brickwork is above the DPC line. Another possible cause of rising damp is leaning paving slabs against a wall, as this bypasses the DPC, allowing moisture to traverse up the external walls. Moisture can travel through building materials, so you should check that there are no materials in contact with the external walls.

Best Treatment Solutions for Rising Damp

There are a number of recommended treatments for rising damp; the most important thing is to source the issue with the existing DPC membrane, then a potential solution can be recommended. Replacing DPC might be possible, however, in many cases, the best solution is an injectable foam to create a new barrier. Removing damaged plaster and applying a waterproof render is merely a temporary solution and without resolving the DPC issue, the damp is likely to return.

If you suspect that rising damp is present in your London home, call London Damp Specialists on 020 8242 9391 or fill out the online survey booking form at the bottom of this page.