Loft condensation

[CharlotteBog]

I have lived in my house for over 25 years.
The loft has always been dry and stuff stored there has remained in good condition.
I went up yesterday to get the Xmas box and noticed the loft felt damp. The joists felt very cold and there were drops of water in some places.
The fabric items in the xmas box smell musty.

Things to factor:
We are in the middle of a very cold snap, following a very warm summer ie. there have been large changes in temp.
We have episode of much heavier rain than we used to have.
I replaced old wooden windows/door with uPVC 5 years ago - house is less draughty.
I got a power shower last year and the pump is in the loft.
I have never had the roof tiles checked, but I guess I'd soon find out if there was a crack/hole!
The loft is not very well insulated.
I am mid terrace.

Where do I start to resolve this? It has motivated me to sort out what's in the loft - to get rid of stuff I don't need and to better protect things I do, but I would like to know if this is something I need to worry about?

What sort of tradesperson might I ask to investigate?

Something has changed probably. Some ideas :

i) Your extraction fans run through the loft and there is a problem with pipe.

ii) You have blocked off the loft ventilation in some way. Lofts need to be ventilated to remove the humidity.

iii) There is a leak somewhere and the leaked water is evaporating causing the loft to be more humid.

iv) You have changed your living conditions below so that you are generating more humidity and that has made the loft more humid.

It could be that the new windows mean that your house in general is more humid. Maybe not causing a problem until this damp period recently. If the loft is poorly ventilated it is possible this extra humid air is making its way into the loft and not being properly ventilated. If this is the case it might be better to remove the humidity from your house

I would start by looking at the humidity in your house. You should be able to get humidity meters for little money on amazon.

I use smart life wi fi monitors in the loft to monitor temperature and humidity. They are about £10 each.

Our loft was damp and we have purchased these ventilators for the felt so far they seem to be helping, cheap and easy to install
Felt Lap Vent White G630 (ukbuildsupplies.com)

We had a similar problem and a roofer fitted ventilation units which sorted it. I agree that probably the work on your house has changed humidity levels.

I would get the roof checked, including the chimney. Following the extensive rain we've had, more roofs are developing new leaks. Roofers have never been so busy from what I hear. It's also possible that existing vent tiles have become blocked.

If your house is noticeably warmer than before and the loft is well insulated, that could be a factor, but if the windows were replaced 5 years ago and this has only just happened, then it is less likely in my view.

Agree on checking the humidity levels generally and perhaps getting a dehumidifier if it's a problem.

Thank you everyone.
I don't need to panic and I have lots of things I can look into and quite quickly and cheaply remedy.
I appreciate the advice.

We've had the exact same problem this year. No changes since we moved into the house but the first time we've had this problem. Got the decorations out of the loft and everything is damp.

Our attic was soaking with condensation. We also fitted the vents that just slot into the felt overlaps. They made a big difference. It’s best to fit them on both sides of the roof so that you get some through-breeze.
I think a lot of houses are very damp this year because it’s been so wet, once the heating goes on all the moisture heats up and travels up into the attic and condenses. So it might just be the wetter autumn that’s responsible rather than a change to your house.

We also fitted the vents that just slot into the felt overlaps. They made a big difference. It’s best to fit them on both sides of the roof so that you get some through-breeze.

You see, this is where I get stuck. How did you know to do this? And when you say "we fitted", you mean you did it yourself, or got someone in?

I don't know if I need to talk to a roof person, a loft person or someone else.

@CharlotteBog we did them ourselves. Really really easy. No tools or know-how required.
If you look at the underside of the roof and can see the felt there are lines where one layer of felt overlaps the next. The vents are just shaped pieces of plastic. You push them between the two layers of felt. They hold the two layers apart which allows air to blow in through the gap.
They’re very basic, no mechanics or electronics. Just a way of holding the felt open. I will find you a link to show you.

This explains it pretty well. Don’t be put off by all the DIY stuff in the intro - it’s much easier than any of that.

You can jump to about 2.40 for the actual vent fitting.

He talks about vented eaves. We don’t have those so relied entirely on the lap vents.

@Helenahandkart

Thank you! I think I'm a little bit in love with Steve. I haven't watched the whole video yet (at work). I do wonder if it's our new shower which has made the difference. We went from crappy, crappy shower to super, amazing power shower.
I will watch properly later and see if it's something I can do myself. My loft isn't boarded out and I don't have a loft ladder so quite as simple as popping up and sorting it out.

I bet he can teach me how to sort my radiators out as well.

Knock knock
Who's there?
Helena
Helena who?
Helena Handcart 😂

That is interesting.

I have vented eaves. The loft never gets too humid, but there is a lot of heat leak into the ceiling because the ceiling insulation terminates before the vents to keep the vents clear.

I would prefer to cover the area over the eave vents completely, but obviously have not done this because I have been concerned over how much that will affect the loft humidity. However, if I install those vents, it will probably allow me to move the insulation further to close off the eave vents while maintaining a decent airflow to prevent humidity build up.

I have humidity meters in the loft so I may try that and see what happens.

You’ll be fine. Just keep to the joists! (I say that as someone who put their foot through the ceiling whilst boarding their own attic 😂)

Steve's great! I am inspired to nip up into the loft send DH up into the loft to sort this out.

Op, is your loft hatch anywhere near your bathroom? Mine is right outside the bathroom door and the steam was working its way up through the gaps around the hatch. There's now insulating tape/bubble wrap around the edges and I have to make sure I keep the bathroom door closed when the shower is in use (I open the window wide and the extractor helps get rid of the steam).

You are a genius!
The hatch is very near the bathroom and not at all well insulated. I wonder if it's something as simple as that.
There isn't tonnes of steam around the house and I do ventilate well after we've used the shower, but it is definitely making more steam than the old crappy one.
This is something I can very easily do myself, and will keep the house warmer.

Thank you.

Ah good to hear! Yes, I have various things in place - strips of bubble wrap taped to the loft side of the hatch work pretty well. Basically anything that stops steam getting through the cracks around the edge. Good luck!