What is causing this damp patch??

Question

I always noticed a damp smell in my London living room but did not know what caused it. When I decided to replace my carpet I lifted the carpet + underlay and I found a small area of damp/wet floorboards around the stone hearth from the previously blocked up chimney. I checked that there was no leaking pipe + I had my chimneys capped with covers incorporating vents for airflow. I have a number of air bricks to allow air flow under the floorboards. But the damp patch has returned! What is the cause?

Answer 1

Hi Stephen, name's Will ...I believe your question still leaves a bit to the imagination. You could clear some things up for me in this fashion ... I am, at this point assuming that your house is completely a wood frame house, I cannot possibly guess as to siding/stucco/etc., but have you per chance thought to check your shingles/ roofing(leaks in roofs have funny ways of showing up where we least extect them), ...what is "ground level" in relationship to the floorboards in question/i.e.,is it possible that your floorboards are wet due to saturation point of soil, if so, prehaps your rain gutters (if you have them) need to have extentions put on your downspouts to dispose of the water further away from the house. If your house is block, check for cracks in the blocking. Good luck in finding your solution and keep in mind that once you do solve your wetness problem, any wood has been a part of this wet problem that is to remain as part of the house should be well cleaned with a good mold killer available at most home builder supply houses such as Home Depot, Lowes, etc. Take care.

Answer 2

Have this problem myself and it is an expensive repair. Every so often the bricks or stones from a hearth have to be waterproofed. If this is not done, the brick/stone acts as a wick for water and then deposits the water at the lowest and/or highest point. In my case, it is the ceiling. Your stonework needs to be watersealed. The unsealed brick or stone will absorb humidity from the air until the stone is saturated which will then slowly release the stored water to another convenient location.

Answer 3

it's very common for roofs to leak around chimneys. you could make sure the chimney has proper flashing or even just get up there with a little tar to spread around it.

Answer 4

You might wan't to check your roof. My brother-in-law and sister bought this house that had simalar problems. We had to rip out the subfloor and put new carpet in. After we put a new roof on.
best of luck stephen.
grev