We had a dormer extention done last year for a bathrom. I have just
had a fault with the ceiling extractor fan and have taken it out of
the ceiling and found that it just vents straight into the roof void,
there are vents in the soffets but I am sure this is not the way to do
it. How should it have been done. Should it vent via a pipe through
the flat roof, and if so how.
Thanks

wrote:
We had a dormer extention done last year for a bathrom. I have just
had a fault with the ceiling extractor fan and have taken it out of
the ceiling and found that it just vents straight into the roof void,
there are vents in the soffets but I am sure this is not the way to do
it. How should it have been done. Should it vent via a pipe through
the flat roof, and if so how.
Thanks

Its not ideal, but its acceptable.

On Tue, 22 Jan 2008 12:16:58 -0800 (PST) someone who may be
" wrote this:-

We had a dormer extention done last year for a bathrom. I have just
had a fault with the ceiling extractor fan and have taken it out of
the ceiling and found that it just vents straight into the roof void,
there are vents in the soffets but I am sure this is not the way to do
it. How should it have been done. Should it vent via a pipe through
the flat roof, and if so how.

Roofs, especially flat roofs, should have as few holes in them as
possible. Zero is the ideal number, as there are then no holes
through which water will probably make its way eventually.

There are a number of ways it should have been done. One of them is
shown in http://www.ventaxia.co.uk/products/d...c/minivent.asp
but depending on your particular circumstances others may be better.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On 22 Jan, 21:11, The Natural Philosopher wrote:
wrote:
We had a dormer extention done last year for a bathrom. I have just
had a fault with the ceiling extractor fan and have taken it out of
the ceiling and found that it just vents straight into the roof void,
there are vents in the soffets but I am sure this is not the way to do
it. How should it have been done. Should it vent via a pipe through
the flat roof, and if so how.
Thanks

Its not ideal, but its acceptable.

The Builders have stated that the extractor flexible pipe should have
gone into the soffets, where there are holes/air vents and it has
somehow become detached, can't see how you could have attached it
though, the holes are lots of small slits. Is this normal?
Thanks

On Wed, 23 Jan 2008 04:01:27 -0800 (PST) someone who may be
" wrote this:-

The Builders have stated that the extractor flexible pipe should have
gone into the soffets, where there are holes/air vents and it has
somehow become detached, can't see how you could have attached it
though, the holes are lots of small slits. Is this normal?

It is normal to discharge air this way, as is illustrated in the
link I posted.

However, the discharge should be through a suitable terminal, which
will have a spigot onto which the ducting is connected. The
companies I mentioned will have suitable terminals in their
catalogues. The small slits are to ventilate the roof space, not to
form the discharge from extractor fans. If the builder did provide a
suitable terminal you will be able to see it, as it will be a
different size/shape to the slots. I suspect you will find that, for
whatever reason, they did not install one.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On 23 Jan, 10:01, David Hansen
wrote:
On Tue, 22 Jan 2008 12:16:58 -0800 (PST) someone who may be
" wrote this:-

We had a dormer extention done last year for a bathrom. I have just
had a fault with the ceiling extractor fan and have taken it out of
the ceiling and found that it just vents straight into the roof void,
there are vents in the soffets but I am sure this is not the way to do
it. How should it have been done. Should it vent via a pipe through
the flat roof, and if so how.

Roofs, especially flat roofs, should have as few holes in them as
possible. Zero is the ideal number, as there are then no holes
through which water will probably make its way eventually.

There are a number of ways it should have been done. One of them is
shown inhttp://www.ventaxia.co.uk/products/domestic/minivent.asp
but depending on your particular circumstances others may be better.

--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

My roof is a flat roof and the soffet overhang is about 3 inches wide,
not wide enough for the outlet grill, the extractor pipe is a bigger
diameter than the overhang. Thanks for the help

On Wed, 23 Jan 2008 07:01:57 -0800 (PST) someone who may be
" wrote this:-

My roof is a flat roof and the soffet overhang is about 3 inches wide,
not wide enough for the outlet grill, the extractor pipe is a bigger
diameter than the overhang.

I assumed that the fan discharged into the original loft, not the
flat roof.

There are oblong terminals, into which oblong ducting can be
connected, if a circular duct is too large to go through something.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Wed, 23 Jan 2008 04:01:27 -0800 (PST) someone who may be
" wrote this:-

The Builders have stated that the extractor flexible pipe should have
gone into the soffets, where there are holes/air vents and it has
somehow become detached, can't see how you could have attached it
though, the holes are lots of small slits. Is this normal?

It is normal to discharge air this way, as is illustrated in the
link I posted.

However, the discharge should be through a suitable terminal, which
will have a spigot onto which the ducting is connected. The
companies I mentioned will have suitable terminals in their
catalogues. The small slits are to ventilate the roof space, not to
form the discharge from extractor fans. If the builder did provide a
suitable terminal you will be able to see it, as it will be a
different size/shape to the slots. I suspect you will find that, for
whatever reason, they did not install one.


Yes. Often they don't. I have run a flexi pipe to a soffit, and put in a
grelle - a special one for the extractor. It was a right bloody fiddle
to get it all installed.

Its so easy to leave it out..and because soffit ventilation is vastly
overspecified (IMO), and chances are no one will ever notice.

On 23 Jan, 15:15, David Hansen
wrote:
On Wed, 23 Jan 2008 07:01:57 -0800 (PST) someone who may be
" wrote this:-

My roof is a flat roof and the soffet overhang is about 3 inches wide,
not wide enough for the outlet grill, the extractor pipe is a bigger
diameter than the overhang.

I assumed that the fan discharged into the original loft, not the
flat roof.

There are oblong terminals, into which oblong ducting can be
connected, if a circular duct is too large to go through something.

--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Thanks, I will look into it