"Tim Lamb" wrote in message
...
In message , ARWadsworth
writes

We were arranging a simple bathroom extractor (timed on exit if
possible)
and realised the added expense of part P. One step further to a heat
recovery, low voltage extractor. But are there any *gotchers*?

Because large parts of the old ducting system are still there, a
centralised system might be possible but issues such as noise, cost of
running a dehumidifier, disposal of condensate, pressure balancing etc.
are a bit mind numbing.

I think we should pursue the cavity insulation aspect despite British
Gas.
I believe the building is based on a concrete frame so the cavities
might
be stopped at each floor.

My parents own the middle floor of a 3 flats. They managed to get cavity
wall insulation done recently. It just needs the people above and below to
have theirs done at the same time. Not everyone paid the same price as my
parents did not qualify for a full discount as it is not their place of
residence. I believe that they paid £150.

A humidistat fan in the bathroom may be better than a timed fan. And what
silly prices have you been quoted for a fan installing?

Huh! Still waiting.

Although the gas main (plastic up to the meter box) has been bonded,
incoming water supply and bathroom piping/metalwork have not.

We discussed fitting an in line ducted extractor with the estimator but,
as has been pointed out, any humidistat would have to be in the bathroom
itself and back to part P.

Unless it is a very small bathroom or the layout is awkard you can have a
humidistat in the bathroom. I realise part P would apply, this in many cases
is very little extra cost. Your additional costs are obviously the incoming
mains bonding and the supplementary bonding (either lots of wires and clamps
or use an RCD for the bathroom electrics). Once the electrics are up to
current standards the only extra cost of part P is the cost of registering
the work when you do a job.



Whatever is done has to be tenant proof.

Indeed. But is that possible?

Cheers

Adam