Coming to the aid of the rescue service
Our Welsh office were asked to examine decay to the front right corner of the North Wales Fire & Rescue Service building in Beaumaris. Due to defects in the cast iron rainwater gutters, excess moisture has been allowed to penetrate the building fabric to cause dry rot. While it’s not quite an emergency it did need prompt action.
Peter Cox to the rescue
Surveyor Mike Jones said: “Due to a concealed defect in the rear face of the cast iron rainwater gutters, excess moisture has been allowed to penetrate the building fabric. This has been absorbed by the adjacent timbers resulting in the germination of the spores of the Dry Rot fungus (Serpula lacrymans) bringing about the breakdown of the timbers to the external wall plate, rafters, jack rafters and valley boards.”
Active dry rot may fill a humid cavity as a cotton wool-like mass, or grow across the surface of the timber as grey-white skin. It has a fresh white or greyish appearance and the relatively impervious outer layer, together with an unusual alkaline tolerance, allows the dry rot to survive in the mortar layers within masonry and walls. It is potentially capable of considerable destruction.
Our team removed the roof covering, hacked off the wall plaster to all affected areas and cut back the original ceiling fixed to the underside of the rafters. We supported existing rafters and cut back seven of them by 1m from the wall plate. We removed the external wall plate full length from the valley and cut back the valley boards by 1m. We then cut back three jack rafters.
Next, the team applied a surface application of fungicidal fluid to the brickwork and wire brushed the surfaces. Holes were formed at 450mm staggered centres in the walls and a fungicidal fluid applied to each hole together with a surface application to the hacked off walls. We renewed the affected timbers ensuring that all contact surfaces were coated with a bituminous solution and capped or laid on PVC DPC membrane.
Saving the day
All exposed timbers used were treated with our fungicidal fluid and all timbers reinstated in contact with, or adjacent to areas of brickwork that were not re-plastered received an application of Peter Cox Timber Water Repellent/Fungicidal fluid.
Mike adds: “The client was so impressed with our work that they also asked us to carry out specialist work to re-stud, insulate and plaster the walls.”