Wet rot attack to a staircase

6 November 2013

Our surveyors and technicians come across many different problems caused by fungal decay attacks. Here we have a case where an outbreak of fungal decay, in this case wet rot, caused damage to a staircase making life for the occupants of the property far from easy.

Timberwise Manchester were called to a property in north Manchester to provide a survey and report looking at possible damp, woodworm and fungal decay issues. The surveyor identified dampness (both rising and penetrating damp), due to a cracked soil pipe from within the rear elevation wall, which allowed severe moisture penetration to the fabric of the building. It was also clear that the pathway levels to the rear elevation were higher in relation to the internal floor. Due to the moisture penetration, the instrumental readings had shown high readings of dampness and soluble salt contamination on internal walls and timbers.

Rising damp is due to moisture rising from the ground into a wall, which also carries soluble salts that can be deposited in the wall fabric and plaster, as the moisture evaporates. Certain salts, in particular chlorides and nitrates, are hygroscopic; which are capable of attracting and absorbing moisture from the atmosphere when the relative humidity is high. As a result this caused damp staining to the rear elevation and ceiling of the dining room, as well as fungal decay to adjacent timbers including the surrounding skirting and staircase. Our Timberwise team recommended an installation of our DriWisetm damp proofing system to create a chemical damp proof course and prevent the moisture penetrating the property. In addition to replastering the walls using limelite renovating plaster as it incorporates a salt deterrent additive.

The fungal decay found was a case of wet rot, which usually occurs in persistently damp conditions, needing an optimum moisture content of 40 – 60 percent to thrive. Unlike dry rot, the conducting strands of wet rot fungi do not extend far from their nutrient wood so they cannot travel through masonry and brickwork. However, wet rot has been known to hollow out giant beams and is responsible for much of the wood decay found in buildings. Although it may not be as serious as dry rot; it is still a common cause of structural defects.

To amend the timber damage, our technician removed the lower treads and risers including stringer, ensuring that all contact surfaces were coated with a liberal coating of fungicidal fluid and capped, or laid, on DPC membrane. In addition to replacing the damaged skirting boards to walls where damp proofing and re-plastering was carried out.

Remedial works carried out on the staircase

Before                                                                  During                                                                After

If you suspect your property has damp issues and is causing problems within your home, it is essential to contact a specialist to identify what is exactly causing the problem and as a result recommend the correct treatments for the property.

Further information about wet rot can be found on our Wet Rot page or you can speak direct to your local Timberwise office for specialist damp or Wet Rot advice on 0800 288 8660 or complete our on-line survey request form to arrange a surveyor to visit.