MegaSack DRAW - This year's winner is user - rgwb
We will be in touch
Just after a bit of confirmation/advise.
I've just noticed that I'm getting condensation in the loft space of my 1970's house. It forms on the inside of the roof, and drips onto the insulation and stuff I store up there. it only happens when it's really cold outside (about freezing).
I'm guessing that the reason is that the air in the loft is warm, hence condensing on the cold roof. If this is the reason I should be able to reduce it by increasing the insulation in the loft (it's not upto current standards). Is that correct?
The other question is whether any long term damage is being done to the roof by this dampness?
Thanks
i looked into this also the other week, websites basically said its either drying of clothes on radiators, showering/baths with out vent etc in bathroom or insulation pushed up to edges of the eaves in the attic blocking air circulation
Yes, when I moved here the insulation was stuffed right into the eaves and it was soaking all the time. I cleared the insulation back which stopped it but either it's come back or I'm just noticing something that always happens in cold (and still) periods.
my attic is doing but i haven't gone up to check, but we do dry our clothes over winter on the rads, that moisture has gotta go some where, saying that i dont usually go up in lofts during winter so cant say i have ever noticed before
Mine does it too-does your central heating system have a header tank in the loft? Sometimes when its working overtime it vents into the header tank (causing some moisture up there). With about 6 people on average living in my house and filling it with moisture I aint suprised that some rises up there too. If it dripping off in constant locations just put a black bin liner up there to catch the drips, they will evapourate again when it warms up.
No header tank in the loft, just water tank. I'm more concerned about long term damage than damp 'junk'.
Thanks for the replies so far.
Same thing happening here in the extreme cold. Ours has just too little ventilation, (could do with more insulation, has 200mm but went to 400mm in last house and it made a difference). We are using a dehumidifier.
http://www.dry-it-out.com/dehumidifier-and-laundry-drier-DD122FW-Mk3
this is really useful, dries clothes quickly and obviously keeps moisture down in the house.
Answer - As per Swampi, and look at levels of insulation-really cheap at B&Q at the mo and amount of ventilation both in the house, and roof - there should be 10mm slot/vent in all the soffits all the way around - ours is a 60s build with a chalet roof, so on one side its ok but on the other there is none, so no cross ventilation. We are also looking at venting tiles, and maybe a positive air system. You may want to look at a de-humidifier if your insulation improvements don't solve the problem. The good thing about a de-humidifier is that at least you will get back the latent heat of condensation which will offset its running costs somewhat (it is essentially a mini heatpump).
you probably have the old felt roofing don't you and no beetle vents in the roof to allow ventilation of the roof space. Do you have soffit vents? The condensation is from a lack of air movement in the space. Increasing the insualtion should help as your preventing heaet from escaping and reducing the dew point. Also, don;t let the insualtion touch the felt at the eaves... you need a 50-100mm gap for ventilation
Yes, looks like roofing felt on the inside. Next time I'll up I'll try and increase the gaps in the eaves. Cheers.