damp loft "just been insulated" gaps question @ eves, edges

allan673

hi, i insulated the loft approx 7 weeks ago. with 170mm insulation. there was already 100mm down.
i noticed a slight damp patch in the upstairs bedroom so i went into the loft and the insulation i layed is quite damp, so is the roof felt :mad: (the north facing side is quite damp, the south side seems not too bad, weird)
i havent noticed it in the last 3 years weve been here, it only seems its since i insulated the loft. part of me wishes i had not bothered doing it.

ive put a dehumidifier up there now to dry it out.

the question im asking is what sort of gap (distance) should i have left between the eves and the insulation, where the insulation meets the eves at the ends. i dont think there is enough ventilation, could it be anything else please.

thanks in advance

andrew-b

Unless your roof has a leak then it sounds like a condensation prob caused by lack of ventilation is the most likely scenario. You need to leave at least an inch or more gap around the eaves..on a day like today you should be able to feel a cold draft coming up from all around the eaves. You could also get a tile or two in the roof replaced with extra vents...could be DIYed i guess if your happy with being at height on roof ladders but not a job i'd entertain doing myself. A roofing company or builder should be able to do this for you though.

But If it's localised to only one specific area (not totally clear from your first post) i would think it's more likely to be a leaky roof - if so take a walk outside with binoculars and have a look to see if any tiles above the area are out of place, cracked, broken etc.

ariba10

We had vent tiles fitted in the roof and that cured the problem we had.

allan673

thanks so much, i have at least a 2 inch gap around the eves so i presume thats ok? there is a patch wetter than other areas so it may be a leak. i will get the ladders out in the morning.

ariba10 - how many vent tiles did you have fitted please? do they go either side of the roof etc? i may go down that road.

is there a certain poition that the vent tiles go? at the bottom, half way up, at the top? cheers