Condensation in my loft

TechnoBoy

I've sent my pregnant wife (second Trimester) into the loft space to fix this.

The loft hasn't been that cold to be honest - not as cold as outside.

Here is a photo of a bit that I got a snap of before she'd finished them all ... this wasn't the worst of it.



And after:



She's also going to move stuff away from the edges.

And then we're going to seal up the holes between the Airing cupboard and the loft, and finally stick the dehumidifier in the loft to get everything started.

Then put a draught strip on the loft-hatch.

Finally, at some point, going to insulate the extractor fan pipes from the two bathrooms.

Update: Insulation's been moved away from the eaves - and boxes moved to give a better airflow.

The holes from the aircupboard to the loft have been filled - though the aircupboard is now a little damp ... I may need to put a ventilation grill in.

I've put a wireless temperature thingy in the loft so I can keep an eye on how warm/cold it is.

The dehumidifier is in the loft and running on maximum - though hasn't collected much water.

The felt looked dryer already --- and it seemed a little more breezy up their.

We'll take the dehumidifier out tonight and keep an eye on the results over the next couple of weeks.

Petrarch74

One of the main causes of condensation is not allowing air flow into the loft space, sometimes over zealous loft installers (not many, mind) can lay the insulation over the soffit vents. You can use very simple eaves ventilation protectors to prevent this. See h**p://guide.rockwool.co.uk/tools/installation-guides/building-insulation/rockprime-blown-loft-insulation.aspx (replace ** with tt).

mickash

TechnoBoy

I have the same problem as you in my loft, your pictures could have been taken in my loft.

Has your condensation been reduced or cleared since you increased the ventilation and blocked up the holes in your ceiling.

I have also moved the dehumidifier up there but in 24 hours only collected about a pint of water and the condensation didn't decrease.

Michael.

TechnoBoy

Hi Michael,

I checked yesterday, when temperatures where -2°C and all the condenstation had cleared and was gone. It was as dry as a bone.

We stopped using the airing cupboard to dry things - I believe this was a major contributor to the water getting into the loft.

The dehumidifier didn't do very much - collected a few dribbles during the course of the day so I removed it.

yakyak

I also recently went up into the loft to put the Xmas decorations back. It seems that the beams are damp to touch, and if rubbed with a finger they leave a black mark. There also seems to be a bit of mould building up in certain areas.

The house was built in 1955, and I recently had a roofer come round to investigate as I thought the flashing had gone. He said that it was down to condentation, but he also said that our roof was in good condition, and that the condensation was nothing to worry about...

Looking at the roof timber, they look to be have been soaked about halfway through. This was partly down to a missing tile I had replaced about a year ago, but in other areas where there were no issues with missing tiles, the timbers feel damp. There is also some evidence of drips of water on the loft boarding I put down. Our roof is felted with some black stuff, it feels quite brittle, but there are no gaps or tears in it. It does feel cold, but I'm not sure if its wet...

The roof has probably been building up condensation for quite a while - a joiner moved our loft hatch to above the landing, he failed to put any insulation around the edge, so I presume that warm air has been seeping through the gap for quite a while. Coupled with the fact that my wife likes the central heating on as she is at home during the day.

Is it worth getting a second opinion with regards the roof condensation? Do the timbers take a long time to dry out?

Strawb_2

i cant believe this problem is happening to so many other people.
I opened the loft hatch about 10 days before Christmas to get the Christmas decor. box down which is inside a polythene bag and everything seemed to be ok.
Yesterday I did the return trip and opened the loft hatch to get the box back to fill with the deceorations and was amazed to find that the top of the polythene bag was wet.
Being cocerned that we had a leak I got the steps out and torch and was horrified to find that water drops were on the inside of the roof felt and had dripped down some of the roof timbers and onto the insulation.
Our house is 11 years old and does have soffit vents running the length of both sides of the house.
the south facing side of the roof was fine and dry and all the condensation was coming off the opposit north facing side of the roof. we have not had this problem before.
I am obviousy concerned about the situation.
Do you think that the problem could be solved by the Easyvent or the plastic water pipe remedies which I have read about on here ?

The roof timbers look new and clean but i am worried about them having got wet...what would anyone reccommend be done with these , if anything ?

amyface

mickash wrote: »

TechnoBoy

I have the same problem as you in my loft, your pictures could have been taken in my loft.

Has your condensation been reduced or cleared since you increased the ventilation and blocked up the holes in your ceiling.

I have also moved the dehumidifier up there but in 24 hours only collected about a pint of water and the condensation didn't decrease.

Michael.

Ditto! - that pic was very similiar to mine - I'd added space blanket in the last 9 months and whilst the eves were not totally blocked by the previously laid insulation, moving some of this at either side to allow more airflow appears to have solved things.

stevelloyd71

mickash wrote: »

TechnoBoy

I have the same problem as you in my loft, your pictures could have been taken in my loft.

Has your condensation been reduced or cleared since you increased the ventilation and blocked up the holes in your ceiling.

I have also moved the dehumidifier up there but in 24 hours only collected about a pint of water and the condensation didn't decrease.

Michael.

New to the forum but we've got exactly the same problem. In the summer of 2008 I added some extra insulation to the loft (house was built in 1969 and the amount of loft insulation was minimal). I put 100mm inbetween the joists and then a further 170mm at right angles to that (We checked that none of the insulation blocked the eaves.)

The condensation during the winter of 2008/9 was absolutely terrible with the roof felt being soaking wet, dripping down onto the boards/insulation and the roof timbers being wet and showing signs of mould growth. I got a roofer in to check this and he installed 8 Marley roof ventilation tiles at a cost of over £600 but we never had any really cold weather after that to see if this solved the problem. I went into the loft in the spring to wipe down and spray mould remover from the roof timbers.

However, the condensation problem is back again just as bad this winter and I'm not really sure what to do now. I really don't have the money to do any further major roof ventilation work.

Does anyone have any experience as to whether it is safe to leave the condensation to occur during the winter months and let the roof dry during the spring/summer - or does this have a risk of the roof timbers become rotten?

Is the simple and cheapest solution to remove some of the loft insulation? Perhaps take off the cross layer of 170mm? We never had any condensation problems before I added the extra insulation - so this should work. Not an ideal solution I know, but it would be the cheapest/easiest solution at this time of short money supply.

Any suggestions/advide would be greatly appreciated.

TechnoBoy

How is water getting into the loft to cause condensation?

Having you filled the holes where the pipes run up to the loft from the the airing cupboard?

Are there any other holes between the loft and the top floor? Is the hatch for the loft got a draft seal on it?

Here's a blog post where I documented how I solved our condensation issue, http://gardenhens.blogspot.com/2009/12/sodden-loft.html .... the key is to stop damp air getting into the loft from the rooms below.

Good luck!

stevelloyd71

TechnoBoy wrote: »

How is water getting into the loft to cause condensation?

Having you filled the holes where the pipes run up to the loft from the the airing cupboard?

Are there any other holes between the loft and the top floor? Is the hatch for the loft got a draft seal on it?


Good luck!

Thanks for the prompt reply TechnoBoy. There is a very small gap around each pipe hole running from the airing cupbroard to the loft. I can't imagine that these would cause such a big problem but I'll seal them up at the weekend anyway.

The loft hatch was uninsulated and didn't have a seal until we had the problem last winter (it was just a square of wood). I added some polystyrene insulation to the back of the hatch and then put some 'P' rubber strip round the edge to seal any gaps. I would like to put a proper loft trap there but our opening seems to be a non standard size (670mm x 670mm approx.)