Client: Housing Association/Property Maintenance Firm
Our client, a housing association in Banbury, tasked Timberwise with surveying a property to investigate dampness, condensation, and timber decay issues. This property was a two-storey residential house of brickwork construction, and was both occupied and furnished at the time of our inspection. The weather conditions were not recorded in the report.
Our preliminary diagnosis identified rising damp on the ground floor, condensation and black spot mould on the first floor, rainwater penetration, and wet rot in external timber joinery. Affected areas included the ground floor lounge, kitchen, rear left bedroom, first floor bedrooms, and the external fascias and soffits.
Challenges
The access for our survey was restricted due to the property’s fitted units, tiled walls, dry linings, and furniture. A full inspect of the bathroom and toilet was also restricted due to the tiled wall surfaces.
Testing of the solid concrete floor slab for damp-proof membrane performance was outside the inspection scope as it required destructive drilling for a full inspection.
Observations
The external inspection of the property revealed a number of problems. Our surveyor noted water staining to the gutter joints and masonry on all elevations, which indicated that they were leaking. The guttering and downpipes were noted to be generally in poor condition and in need of repair or replacement.
There was external cracking of the building’s brickwork, with stepped cracking found on the front, right, and rear elevations. The lintel above the front right window also needed attention from a structural surveyor.
Wet rot decay was found on the facia and soffits of all elevations during the inspection.
The internal inspection found an ongoing rising damp problem that was identified on the ground floor walls, with visible moisture in the lounge and kitchen internal wall caused by a breakdown of the existing damp proof course. High moisture metre readings were recorded on both the exposed internal and external masonry, with hygroscopic salt deposits (chlorides and nitrates) present in both the wall fabric and plaster.
The property was also suffering from a condensation problem. Moisture profiles taken indicated widespread condensation due to lack of extraction units in the kitchen, bathroom, and utility room, which had led to black spot mould growing in the first-floor bedrooms.
Water-stained, visibly damp, and defective plaster in the rear left bedroom was also found, which had resulted from rainwater penetration through the defective gutters and porous external brickwork.
A visual internal inspection indicated the upper surface of the concrete floor was dry at the time of survey, which suggested the presence of an underlying damp-proof membrane.
Solutions
To prepare the area for treatment, our team taped down dust sheets and hardboard to floor surfaces in working areas to reduce the amount of dust settling. Any free-standing items that couldn’t be moved were covered in a protective sheeting. All salt-contaminated wall plaster was hacked off and removed, before the removal of all of the existing timber skirting boards from treatment areas.
For the damp proofing, we drilled mortar joints at pre-determined centres and installed a DryTek DPC System horizontally along designated ground floor walls. We then injected a vertical DPC chemical barrier to prevent damp abridgement from the adjoining masonry.
We re-plastered the affected ground floor walls to a height of one metre using a salt-retardant DryTek Finishing System. The wall-to-floor junctions were then sealed below plaster level with a waterproof compound to prevent upward moisture vapour transmission.
We also removed all of the debris and waste accumulated from the project away from the site, to be disposed of properly.
We also strongly advised the client to source external contractors to repair the defective external guttering and testing the porous brickwork to prevent any further penetration from rainwater. The external decayed joinery, the fascias and soffits, would also have to be repaired or replaced.
Further recommendations were to also source a contractor to install extract units in the kitchen and bathroom, with the possible addition of a ceiling-mounted Positive Input Ventilation (PIV) system on the first-floor landing to help with the condensation and atmospheric moisture.
Skirting boards, kitchen units, and electrical fittings were to be replaced only after a drying period had elapsed.
Results
Our team successfully established an effective chemical horizontal DPC barrier to prevent capillary groundwater movement. We prevented hygroscopic salt migration to decorative surfaces using a specialised finishing system. We effectively provided the client with long-term structural preservation of their home, along with damp control, across all of the affected ground and first floor areas.
Do You Want Help with a Damp Solution?
Our dedicated and experienced team in Banbury are ready to talk to you about your options for property preservation. Don’t hesitate to call us on 0800 288 8660, or you can request a survey online.
