Damp Proofing

Damp bay wall and rotten floor joists - how to remedy?

Anonymous user 09/03/2024 - 3.31 PM

I have a damp issue that's affecting the bay window area and sub floor in my mid-terrace late Victorian house. From further investigations, including a report from an independent surveyor, this seems likely to have been caused by poor ventilation and the action taken by the previous owners to 'seal' the property up (covering up air bricks, UPVC windows etc). On the exterior of the wall, below the window, there is a layer of what looks to be textured/painted concrete render - this goes around the entire bay and into an adjoining porch. This then meets a plinth that has no obvious stop beading where it meets the render. I have already dug out a French drain which has fully exposed an existing air brick. The rest of the upper wall bricks are coated in white paint (I'm not sure if the pointing had been redone with cement). I've had several quotes for remedial work, but having trouble finding a holistic approach to resolving. Even companies who concede that the issue is not related to rising dampness still want to inject the wall and replaster with a waterproof sand and cement mix. I'm very reluctant to do this with the age of the property, thinking that it may make things worse in the long term. But I also can't afford to leave the problem for much longer. Would one solution be to remove the concrete render at the exterior and restore the brickwork with lime mortar? And on the inside, replaster with lime? I'm concerned with what state the exterior bricks may be in underneath if attempting this. I definitely need to sort the rotten timbers/wall plates out near the wall as a matter of urgency. Many thanks.