Will soffit vents solve condensation problem?

[JohnD]

if you have (effectively) a hot bath steaming night and day in your loft, then that has got to be the first thing to deal with.

 

[Glengyle]

John, can you suggest a suitable sealant/gel/seal to create an airtight bond between the hot water tank and lid. I enclosed the open ends of existing WBP ply lid and covered it with thick black polythene sheet (the stuff you use for preventing weeds popping up), then wrapped the tank and covered the lid with space blanket and loft insulation. Left it overnight but when I checked this morning there has been a slight leakage at one end of the lid - there was some moisture on the insulation. The top edge of the tank which the lid sits on is about 20mm wide aluminium.

ps, a combi boiler is now top of the household maintenance list for next year.

 

[kevnurse]

IMHO you should take this additional problem to the plumbing forum. I'm not sure that you should seal that tank. Not only is it a hot water store, but it appears to be an expansion vessel as well. Its a very strange set up.

 

[Glengyle]

Thanks Kev. When you say expansion vessell what do you mean? There is an overflow pipe from the tank to outside the house so presumably this would prevent the tank being fully sealed.

 

[kevnurse]

OK, you didn't mention the overflow pipe, so you should be OK to seal the tank, but this is a very strange hot water system. I've never heard of a hot water tank in the loft. I have regularly heard of a cold water tank becoming hot due to a system failure, which is what I think you have. Before you permanently seal the tank, write to the plumbing forum, sort out the hot water problem, if required, and the loft condensation should disappear.

 

[Glengyle]

It is definitely a hot water tank. It has a label with the name of the tank on the side - can't remember it off hand but I'll check during the week. The next door neighbour had the same set-up. I'll ask the plumbing forum about the sealing. Cheers.

 

[kevnurse]

As you have seen, the plumbers are not au fait with your arrangement. Can you send in a photo? There are some instructions at the top of this page: "Upload pictures" should help....

Kev

 

[Glengyle]

Hi Kev, one or two of the plumbers will be pleased to know that I no longer intend sealing the lid to the tank. After fitting a lid to the cold water feeder part of the tank (this lid was missing, got my neighbours old one) there is no moisture leakage from the tank - the insulation I covered the tank with is dry. If/when I remove the insulation again I will take some photos and add to the plumbing thread. Also the roof boards seem to be drying out now

Thanks again folks.