Serious condensation these cold mornings

Ricky2 · 17 Dec 2007

7year old 4 bedroom house in Cornwall conventional tiled roof

Went up in loft 2 days ago and was alarmed to see water drips on the loft floor. There are no water pipes in roof so assumed had a leak

Further investigation showed it to be very heavy condensation starting in the very apex of the roof timbers and following the black fabric all the way down to the walls

We have vents about every 18" around the soffits so assumed there would be plenty of air, but obviuosly this is not the case

Am tempted to out an airbrick each end of the roof for better airflow

Does this make sense please?

noseall · 17 Dec 2007

yes it does make sense.

is the loft ceiling insulated?

if so, how thick is the insulation?

Ricky2 · 17 Dec 2007

Yes Noseall it is insulated
About 10" thick I would guess, double in places
Centre part is boarded over the insulation with chipboard flooring (which is how I saw the drips)
Only exception is the loft hatch, plastic with some sort of insulation incorporated

Just been up there to check on how a de-humidifier I stuck up there this morning is working. Got about 1/3 pot already and roof directly above it is drier. Also wind now got up in Cornwall and seems to make a difference

Thanks for the help

JohnD · 17 Dec 2007

do you ALWAYS use the extractor in the bathroom?

does anyone drape wet washing about the house?

do you use an unvented tumble drier?

are there any water tanks in the loft?

is the loft hatch a tight fit?

Ricky2 · 17 Dec 2007

John Thanks

Never use the extractors. Use window in times of need!
Washing is dried in the dryer (which is vented thru' wall to outside)
Absolutely no water pipes or tanks in loft. Boiler is a combi and no storage tanks anywhere
Loft hatch is a perfect fit

House generally is very very dry and have to use water thingys clipped on the raditaors in a few rooms to add some humidity and avoid static shocks.

weird isn't it!!!

JohnD · 17 Dec 2007

my guess is that water vapour is rising up from the house, especially from the bathroom. It gets through gaps round lamp fittings and ceiling switches, also round pipes if you have any going through the ceiling.

Warm dry air in the house holds much more water than cold damp air in the loft.

go up into the loft on a cold frosty night with a torch and look for any rising steam.

extra ventilation in the loft will help, pref at opposite ends so you get a through-current of air.

Ricky2 · 18 Dec 2007

Wonderful suggestion John thank you. Will try that with a torch.
Am making great prgoress drying out with the de-humidifier
Will then go up when its raining next to make sure there is no leak
Assuming there isn't will get local builder to put an airbrick each end of the roof

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Serious condensation these cold mornings

Similar threads