Bathroom extractor venting into roof space

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Recently we had a loft extension, including a bathroom. Now winter is here we've noticed the ceiling extractor blows a cold gale in when the wind comes from the West, so I decided to find the vent outlet. Took the fan off and lo and behold - no ducting. They have left it venting into the roof space (see photo).

There is actually a lot of air blowing around up there and no evidence of dampness to my surprise, all that steam must be condensing as soon as it gets through the fan, no steam is apparent coming from anywhere outside the house. But this is still problematic, I'm concerned it might cause damp in the long run, and more importantly I can't see how to prevent arctic air blowing into the bathroom.

One option would be to fit a small length of duct with an internal non-return vent in it but if I fit ducting it might lead to condensation dripping back down into the fan. There's no access up there, the board you can see in the photo is the flat roof.

Any suggestions?

 
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I suggest you get the bandits who did the loft conversion to come back and bring their work into compliance with the law.
 
I suggest you get the bandits who did the loft conversion to come back and bring their work into compliance with the law.

I plan to, but can you tell me what is necessary? Does the law require ducting? A condensation trap?

Thanks!
 
From Part F of building regs...

5.5
Extract ventilation to outside is required in each kitchen, utility room
and bathroom and for
sanitary accommodation.
The extract can
be either intermittent or continuously operating.
The intermittent rate, and for continuous systems
the minimum extract air flow rates at the highest
and lowest settings, should be no less than
specified in Table 5.1a.

Yours doesnt go outside. Can it not be ducted to a vent in the fascia?

I think my main concern would be if the builder was this rough, what else is not done correctly??
 
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The law in this case is the Building Regulations, and specifically Parts C & L, but as you can see they don't explicitly require ducting. They don't explicitly require anything, in fact, not even in terms of performance.

Approved Documents C & L will contain guidance which if followed will lead to compliance. You're always free to find other ways to comply - doing what the ADs advise is never compulsory. It can be perverse to look for alternatives though, and I doubt you'd be ably to comply without ducting.

And I think you may have wider problems, but I'm not a builder or a roofer, so you should look into this via the Building forum. I'd be surprised if Building Control would approve a cold deck flat roof these days - warm deck is much preferred, so if what's on show is the bottom layer of a warm deck then there should not be air blowing around in the void, and the air there should not be cold. If it is a cold deck then removing insulation for a fan and a duct is a no-no, as is breaching the vapour control layer that you must have between the plasterboard and the insulation.

Who drew up the plans, wrote the specifications, and applied for Building Regulations approval for the extension?

By whom, and at what stages, was the work inspected?
 
Thanks Simon35. I agree, it is a bit worrying. They have been around for a very long time though, and this is the only issue so far.

Can anyone tell me if there are implications for us having a fan that was installed in a way that does not meet regs? Would it invalidate insurance for example?

Also, I expect the company will play ball, but what rights do I have if they refuse to put it right? The build is 6 months old.
 
And I think you may have wider problems, but I'm not a builder or a roofer, so you should look into this via the Building forum. I'd be surprised if Building Control would approve a cold deck flat roof these days - warm deck is much preferred, so if what's on show is the bottom layer of a warm deck then there should not be air blowing around in the void, and the air there should not be cold. If it is a cold deck then removing insulation for a fan and a duct is a no-no, as is breaching the vapour control layer that you must have between the plasterboard and the insulation.

Who drew up the plans, wrote the specifications, and applied for Building Regulations approval for the extension?

By whom, and at what stages, was the work inspected?

OK, this is worrying me now. I believe it is a cold deck design. There are ventilation grills all the way under the gutters outside, and there is a LOT of cold air blowing around above the insulation. I can't see a vapour control layer between plasterboard and insulation.

The plans were drawn up by the loft-extension company, they sell a package where they arrange all applications and inspections. I believe the inspections were done twice, once at the early stages, and once at the end.

How serious a problem might all this be?
 
this is the only issue so far.
That you know of. Also, things like condensation-induced rot, or insulation-related bills and damp can take a while to realise. Ditto structural if the roof turns out to be unable to withstand gales, or heavy snow, or someone walking on it.


Can anyone tell me if there are implications for us having a fan that was installed in a way that does not meet regs? Would it invalidate insurance for example?
It would probably mean you'd not succeed with any claims for damage due to condensation - doubt it would mean that your whole buildings insurance became null and void.


Also, I expect the company will play ball, but what rights do I have if they refuse to put it right?
https://www.gov.uk/make-court-claim-for-money/overview
 
It is of course possible that it could have been a mistake.

A neighbour of mine had a similar occurrence. Usually the builder makes the duct openings as well as fitting the duct and grilles. Then his electrician comes along and wires it up. In this instance, the electrician came first. Because the fan was not installed, and not wanting to have to come back later just for the fan, he fitted it into the ceiling and wired it up, assuming that the builder whom he had worked with on other jobs would make the opening in the outside wall and fit the duct as he had done before. When the builder arrives he sees the fan installed and assumes the job is done.

When it was discovered, the builder was very apologetic and came the next day to finish it off.

So the best thing you can do is contact the builder and see what he says.
 
Just a bit of empathy really. I've made a couple of silly mistakes recently :oops: and have been very appreciative of the understanding of others :D
 
You're right stem, they are completely happy to come and fix the ducting issue and acknowledge it was a mistake. not sure how they will manage that as it is a long way up in the air and has been decorated to a high standard!

Regarding the roof design, it is built according to the planned specification as a cold deck. If I had known more I might have asked for a warm roof, but I certainly can't claim they did anything wrong there.
 

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