Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather
(like we have at the moment). There's no obvious signs of damp around
the walls or floor and everything seems dry. The room is shaded with a
large hedge running to the side of it (if this makes any difference).
What could cause this problem and what can we do about it? It's not very
pleasant to be in the room.

Thanks

--
John Kelly

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John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this makes
any difference). What could cause this problem and what can we do
about it? It's not very pleasant to be in the room.

Thanks


Check the ceiling for any slight dampness which may not be visible.
Leave the window open slightly for a week or two to allow it to dry out
properly.
Last resort: get a dehumidifier and leave it running for a few weeks.

Phil L wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this makes
any difference). What could cause this problem and what can we do
about it? It's not very pleasant to be in the room.

Check the ceiling for any slight dampness which may not be visible.
Leave the window open slightly for a week or two to allow it to dry out
properly.
Last resort: get a dehumidifier and leave it running for a few weeks.

The window's been open (on the latch) since March. There's no sign of
dampness in the plaster or the floor. The air is heavy with damp though.
Is it somethig as simple as not yet having laid a floor (we're going to
put tiles down) in there?


--
John Kelly

remove dimspam if replying by email

"John Kelly" wrote:
Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather (like
we have at the moment). There's no obvious signs of damp around the walls
or floor and everything seems dry. The room is shaded with a large hedge
running to the side of it (if this makes any difference). What could cause
this problem and what can we do about it? It's not very pleasant to be in
the room.

Thanks

--
John Kelly

remove dimspam if replying by email

If it smells damp then it's damp. Even if the hedge shields the extension
from the sun I doubt that cutting the hedge down will fix the problem. I
would start with the floor, which I presume is concrete, and spread some
newspaper out and cover with a tarpaulin or plastic sheet. Check after a few
days to see if the paper is damp. Obviously it should be dry. The only DIY
way of checking the walls for damp I know of is to fix small pieces of glass
to the plaster with a ring of plasticine or putty, so that there is a space
between the plaster and the glass, and the air is sealed under the glass.
Check after a few days - if the glass mists up on the inner surface then
that indicates that moisture from the wall is condensing out onto the glass.
Have you reported your concerns to the builder? Has it got a flat roof? Is
that watertight? You could get a survey/damp report done by a chartered
surveyor or structural engineer.

"John Kelly" wrote:
The window's been open (on the latch) since March. There's no sign of
dampness in the plaster or the floor. The air is heavy with damp though.
Is it somethig as simple as not yet having laid a floor (we're going to
put tiles down) in there?


--
John Kelly

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I wouldn't lay tiles or anything else on the floor until the cause of the
damp smell is found, in case the source of the damp is the floor.

Phil Anthropist wrote:
"John Kelly" wrote:
Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather (like
we have at the moment). There's no obvious signs of damp around the walls
or floor and everything seems dry. The room is shaded with a large hedge
running to the side of it (if this makes any difference). What could cause
this problem and what can we do about it? It's not very pleasant to be in
the room.

Thanks

--
John Kelly

remove dimspam if replying by email

If it smells damp then it's damp. Even if the hedge shields the extension
from the sun I doubt that cutting the hedge down will fix the problem. I
would start with the floor, which I presume is concrete, and spread some
newspaper out and cover with a tarpaulin or plastic sheet. Check after a few
days to see if the paper is damp. Obviously it should be dry. The only DIY
way of checking the walls for damp I know of is to fix small pieces of glass
to the plaster with a ring of plasticine or putty, so that there is a space
between the plaster and the glass, and the air is sealed under the glass.
Check after a few days - if the glass mists up on the inner surface then
that indicates that moisture from the wall is condensing out onto the glass.
Have you reported your concerns to the builder? Has it got a flat roof? Is
that watertight? You could get a survey/damp report done by a chartered
surveyor or structural engineer.

Thanks - I'll be very upset if it is damp. We paid the builder off back
in march and it'll be difficult to get him back - we has a problem with
a badly installed window and he wasn't very good about it. I'll try the
paper and the glass bit and see. At the moment I've got a sheet of
plastic on the floor which I assume is the same as putting glass on the
wall - ie: it may get damp in a few days. Seems odd though that the room
only feels damp when damp outside.

--
John Kelly

remove dimspam if replying by email

John Kelly wrote:
Phil L wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this
makes any difference). What could cause this problem and what can
we do about it? It's not very pleasant to be in the room.

Check the ceiling for any slight dampness which may not be visible.
Leave the window open slightly for a week or two to allow it to dry
out properly.
Last resort: get a dehumidifier and leave it running for a few weeks.

The window's been open (on the latch) since March. There's no sign of
dampness in the plaster or the floor. The air is heavy with damp
though. Is it somethig as simple as not yet having laid a floor
(we're going to put tiles down) in there?

The bare floor shouldn't make any difference.
What kind of roof is on it, flat or pitched?
Is there insulation in the roofspace?
What is the plaster construction? - EG, drylined, render, bonding, browning
etc?

John Kelly wrote:
Phil Anthropist wrote:
"John Kelly" wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this makes
any difference). What could cause this problem and what can we do
about it? It's not very pleasant to be in the room.

Thanks

--
John Kelly

remove dimspam if replying by email

If it smells damp then it's damp. Even if the hedge shields the
extension from the sun I doubt that cutting the hedge down will fix
the problem. I would start with the floor, which I presume is
concrete, and spread some newspaper out and cover with a tarpaulin or
plastic sheet. Check after a few days to see if the paper is damp.
Obviously it should be dry. The only DIY way of checking the walls for
damp I know of is to fix small pieces of glass to the plaster with a
ring of plasticine or putty, so that there is a space between the
plaster and the glass, and the air is sealed under the glass. Check
after a few days - if the glass mists up on the inner surface then
that indicates that moisture from the wall is condensing out onto the
glass. Have you reported your concerns to the builder? Has it got a
flat roof? Is that watertight? You could get a survey/damp report done
by a chartered surveyor or structural engineer.

Thanks - I'll be very upset if it is damp. We paid the builder off back
in march and it'll be difficult to get him back - we has a problem with
a badly installed window and he wasn't very good about it. I'll try the
paper and the glass bit and see. At the moment I've got a sheet of
plastic on the floor which I assume is the same as putting glass on the
wall - ie: it may get damp in a few days. Seems odd though that the room
only feels damp when damp outside.

Sorry - no it hasn't got a flat roof. Forgot to add that bit

--
John Kelly

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"John Kelly" wrote:

Sorry - no it hasn't got a flat roof. Forgot to add that bit

So it's got a sloping roof with tiles? Can you look into the roof space to
check for signs of damp? What are the walls made of, brick outside, then an
insulation-filled cavity, then blocks inside, then internally plastered, or
some other construction?

Phil L wrote:
John Kelly wrote:
Phil L wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this
makes any difference). What could cause this problem and what can
we do about it? It's not very pleasant to be in the room.
Check the ceiling for any slight dampness which may not be visible.
Leave the window open slightly for a week or two to allow it to dry
out properly.
Last resort: get a dehumidifier and leave it running for a few weeks.
The window's been open (on the latch) since March. There's no sign of
dampness in the plaster or the floor. The air is heavy with damp
though. Is it somethig as simple as not yet having laid a floor
(we're going to put tiles down) in there?

The bare floor shouldn't make any difference.
What kind of roof is on it, flat or pitched?
Is there insulation in the roofspace?
What is the plaster construction? - EG, drylined, render, bonding, browning
etc?

The roof is a standard clay tiled roof - not flat. There is insulation
in the roofsapce. The new walls were built with that insulation board
between them and the plasterboard was bonded onto the walls and then
plastered over - drylined.

The only thing that concerned me at the time was when they concreted the
floor. Where they'd knocked through they put slate on what was left of
the old wall and then concreted over that. I asked if it needed anything
else and they said no.

--
John Kelly

remove dimspam if replying by email

Phil Anthropist wrote:
"John Kelly" wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this
makes any difference). What could cause this problem and what can we
do about it? It's not very pleasant to be in the room.

Thanks

--
John Kelly

remove dimspam if replying by email

If it smells damp then it's damp. Even if the hedge shields the
extension from the sun I doubt that cutting the hedge down will fix
the problem. I would start with the floor, which I presume is
concrete, and spread some newspaper out and cover with a tarpaulin or
plastic sheet. Check after a few days to see if the paper is damp.
Obviously it should be dry. The only DIY way of checking the walls
for damp I know of is to fix small pieces of glass to the plaster
with a ring of plasticine or putty, so that there is a space between
the plaster and the glass, and the air is sealed under the glass.
Check after a few days - if the glass mists up on the inner surface
then that indicates that moisture from the wall is condensing out
onto the glass. Have you reported your concerns to the builder? Has
it got a flat roof? Is that watertight? You could get a survey/damp
report done by a chartered surveyor or structural engineer.

Damp meters can be hired from plant hire shops, although they are fairly
expensive.....I'm a bit concerned about the walls being damp in a newbuild,
considering the blistering heatwave of a few months back, it /should/ be
bone dry by now...

John Kelly wrote:
Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather
(like we have at the moment). There's no obvious signs of damp around
the walls or floor and everything seems dry. The room is shaded with a
large hedge running to the side of it (if this makes any difference).
What could cause this problem and what can we do about it? It's not very
pleasant to be in the room.

I'm no expert by any means but when we had our extension built last
year I had a kind of similar problem. I looked up in the loft about 8
weeks after the build was complete only to find huge amounts of
moisture up there. It's a sealed loft (as is usual these days) with a
breathable membrane under the slates. But the membrane was obviously
nowhere near breathable enough to cope with the vast quantity of water
that has to dry out of a new build.

I put a dehumidifier in the upstairs room with the loft hatch (open)
and collected about 4 litres per day for 3-4 weeks. By then the loft
was dry, and it's never beena problem since.

I wonder if its possible that your loftspace could be harbouring a lot
of dampness?
Do you have a loft hatch?
Might be worth getting a dehumidifier in anyway.
Have you done your Building Control final sign-off yet? The BCO might
have some advice?

Jon.

On Sat, 02 Sep 2006 16:47:18 +0100, John Kelly
wrote:

|Our home had an extension built earlier this year. The extension was to
|the side of the house and involved knocking through. After 7 months the
|room smells damp or musty and seems particularly bad in damp weather
|(like we have at the moment). There's no obvious signs of damp around
|the walls or floor and everything seems dry. The room is shaded with a
|large hedge running to the side of it (if this makes any difference).
|What could cause this problem and what can we do about it? It's not very
|pleasant to be in the room.

Suggest you get the room as hot as you can for as long as you can. say
25-30 deg C for a week, with thermostated heaters. That should dry out
the walls, floor and roof. Do it before the warm weather ends and makes
the method *still* more costly.

Also put some extra insulation anywhere you can.

Brute force and ignorance sometimes works where other things have failed.

I have read the rest of the thread.
--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

Phil Anthropist wrote:
"John Kelly" wrote:

Sorry - no it hasn't got a flat roof. Forgot to add that bit

So it's got a sloping roof with tiles? Can you look into the roof space to
check for signs of damp? What are the walls made of, brick outside, then an
insulation-filled cavity, then blocks inside, then internally plastered, or
some other construction?

Yep - also it has plasterboard bonded to the breezeblock and then
plastered.

Unfortunately we can't look into the roofspace but the ceiling is very dry.

--
John Kelly

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Dave Fawthrop wrote:
On Sat, 02 Sep 2006 16:47:18 +0100, John Kelly
wrote:

|Our home had an extension built earlier this year. The extension was to
|the side of the house and involved knocking through. After 7 months the
|room smells damp or musty and seems particularly bad in damp weather
|(like we have at the moment). There's no obvious signs of damp around
|the walls or floor and everything seems dry. The room is shaded with a
|large hedge running to the side of it (if this makes any difference).
|What could cause this problem and what can we do about it? It's not very
|pleasant to be in the room.

Suggest you get the room as hot as you can for as long as you can. say
25-30 deg C for a week, with thermostated heaters. That should dry out
the walls, floor and roof. Do it before the warm weather ends and makes
the method *still* more costly.

Also put some extra insulation anywhere you can.

Brute force and ignorance sometimes works where other things have failed.

I have read the rest of the thread.

I'm good at brute force and ignorance :-)

--
John Kelly

remove dimspam if replying by email

Tournifreak wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather
(like we have at the moment). There's no obvious signs of damp around
the walls or floor and everything seems dry. The room is shaded with a
large hedge running to the side of it (if this makes any difference).
What could cause this problem and what can we do about it? It's not very
pleasant to be in the room.

I'm no expert by any means but when we had our extension built last
year I had a kind of similar problem. I looked up in the loft about 8
weeks after the build was complete only to find huge amounts of
moisture up there. It's a sealed loft (as is usual these days) with a
breathable membrane under the slates. But the membrane was obviously
nowhere near breathable enough to cope with the vast quantity of water
that has to dry out of a new build.

I put a dehumidifier in the upstairs room with the loft hatch (open)
and collected about 4 litres per day for 3-4 weeks. By then the loft
was dry, and it's never beena problem since.

I wonder if its possible that your loftspace could be harbouring a lot
of dampness?
Do you have a loft hatch?
Might be worth getting a dehumidifier in anyway.
Have you done your Building Control final sign-off yet? The BCO might
have some advice?

It's all been signed off and the builder's long gone - they finished in
early March. I may open up the roofspace anyway. I do feel a little
uncomfortable having a space in a house which I can't get to. The
builders seemed to think I was being silly suggesting such a thing
telling me it would spoil the look of the ceiling. By this time (4
months down the line) I was just wanting them to finish and go so left it.

--
John Kelly

remove dimspam if replying by email

The message
from John Kelly contains these words:

I'm good at brute force and ignorance :-)

I can do both at once!

--
Skipweasel
Pay no attention to that man behind the curtain.

Tournifreak wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this
makes any difference). What could cause this problem and what can we
do about it? It's not very pleasant to be in the room.

I'm no expert by any means but when we had our extension built last
year I had a kind of similar problem. I looked up in the loft about 8
weeks after the build was complete only to find huge amounts of
moisture up there. It's a sealed loft (as is usual these days) with a
breathable membrane under the slates. But the membrane was obviously
nowhere near breathable enough to cope with the vast quantity of water
that has to dry out of a new build.

I put a dehumidifier in the upstairs room with the loft hatch (open)
and collected about 4 litres per day for 3-4 weeks. By then the loft
was dry, and it's never beena problem since.

I wonder if its possible that your loftspace could be harbouring a lot
of dampness?
Do you have a loft hatch?
Might be worth getting a dehumidifier in anyway.
Have you done your Building Control final sign-off yet? The BCO might
have some advice?

Jon.

Newbuild should also have crossflow ventilation in roof spaces, usually a
soffit vent running the full length of the fascia board and airbricks in the
walls or ridge vents on the roof..what may have happened here is that they
have blocked the effectiveness of the soffit vent with insulation pushed too
tightly against the joist ends.

Phil L wrote:
Tournifreak wrote:
John Kelly wrote:
Our home had an extension built earlier this year. The extension was
to the side of the house and involved knocking through. After 7
months the room smells damp or musty and seems particularly bad in
damp weather (like we have at the moment). There's no obvious signs
of damp around the walls or floor and everything seems dry. The room
is shaded with a large hedge running to the side of it (if this
makes any difference). What could cause this problem and what can we
do about it? It's not very pleasant to be in the room.
I'm no expert by any means but when we had our extension built last
year I had a kind of similar problem. I looked up in the loft about 8
weeks after the build was complete only to find huge amounts of
moisture up there. It's a sealed loft (as is usual these days) with a
breathable membrane under the slates. But the membrane was obviously
nowhere near breathable enough to cope with the vast quantity of water
that has to dry out of a new build.

I put a dehumidifier in the upstairs room with the loft hatch (open)
and collected about 4 litres per day for 3-4 weeks. By then the loft
was dry, and it's never beena problem since.

I wonder if its possible that your loftspace could be harbouring a lot
of dampness?
Do you have a loft hatch?
Might be worth getting a dehumidifier in anyway.
Have you done your Building Control final sign-off yet? The BCO might
have some advice?

Newbuild should also have crossflow ventilation in roof spaces, usually a
soffit vent running the full length of the fascia board and airbricks in the
walls or ridge vents on the roof..what may have happened here is that they
have blocked the effectiveness of the soffit vent with insulation pushed too
tightly against the joist ends.

The fascia board is solid. No airbricks either from what I can make out.
The building inspector person seemed perfectly happy with it all when he
came round.

--
John Kelly

remove dimspam if replying by email

John Kelly wrote:
Phil L wrote:

Newbuild should also have crossflow ventilation in roof spaces,
usually a soffit vent running the full length of the fascia board
and airbricks in the walls or ridge vents on the roof..what may have
happened here is that they have blocked the effectiveness of the
soffit vent with insulation pushed too tightly against the joist
ends.

The fascia board is solid. No airbricks either from what I can make
out. The building inspector person seemed perfectly happy with it all
when he came round.

'Breathable' undefelt is *not* sufficient on it's own, I'm surprised the
plans were passed or the BCO let this go like this.
I meant the soffit vents are behind the fascia, is there a gap between
fascia and wall? - if so is there a plastic slotted vent, sometimes only an
inch across? - roof vents? (like raised tiles with a slot in them?)

Aslo in one of your earlier posts, you mentioned that you had polythene down
on the floor in this room? - if you lift it up, does the smell get worse and
is there any moisture underneath it?...either way I would leave this off the
floor for a while, in case it's trapping moisture in.

If you have no luck, you may have to cut an access hatch into the ceiling
and inspect the insulation for condensation, but if it were mine, the next
course of action would be a dehumidifier.

Phil L wrote:

'Breathable' undefelt is *not* sufficient on it's own, I'm surprised the
plans were passed or the BCO let this go like this.
I meant the soffit vents are behind the fascia, is there a gap between
fascia and wall? - if so is there a plastic slotted vent, sometimes only an
inch across? - roof vents? (like raised tiles with a slot in them?)

No there isn't. Like I say the building inspector did his usual turn up,
have a cup of tea, chat to the builders, and leave. Do they inspect
anything? Having said that he did insist the footings went down about
twice as deep as the builders had dug them so maybe he just knows what t
look for.

Aslo in one of your earlier posts, you mentioned that you had polythene down
on the floor in this room? - if you lift it up, does the smell get worse and
is there any moisture underneath it?...either way I would leave this off the
floor for a while, in case it's trapping moisture in.

It's bone-dry under the polythene. I've also put a newspaper on the
floor to see if it gets damp. After one night it's also dry.

If you have no luck, you may have to cut an access hatch into the ceiling
and inspect the insulation for condensation, but if it were mine, the next
course of action would be a dehumidifier.

Which, by chance, having come from a damp house previously, we have in
storage somewhere. Never thought I'd be digging it out for a new
extension though. I'm hoping that this is just damp from the building
process and once it's all dry then it won't need any more drying out.

Today it smells fine. Is it a co-incidence that yesterday was bucketing
down all night and day and today it isn't and yesterday it stunk of damp
and today it doesn't?

--
John Kelly

remove dimspam if replying by email

John Kelly wrote:

Today it smells fine. Is it a co-incidence that yesterday was bucketing
down all night and day and today it isn't and yesterday it stunk of damp
and today it doesn't?

Where does the rainwater go?. Leak in gutter, down pipe, drain disturbed
by new foundation?

djc wrote:
John Kelly wrote:

Today it smells fine. Is it a co-incidence that yesterday was
bucketing down all night and day and today it isn't and yesterday it
stunk of damp and today it doesn't?

Where does the rainwater go?. Leak in gutter, down pipe, drain disturbed
by new foundation?

Should be okay as the drain is all new. I'll lift the drain cover and
make sure it is all going where it should be. Bit stuck for time now as
(unfortunately my lottery numbers didn't come up) I've got a weeks work
to do :-(

--
John Kelly

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On Sat, 2 Sep 2006 21:32:35 +0100, Guy King
wrote:

The message
from John Kelly contains these words:

I'm good at brute force and ignorance :-)

I can do both at once!

You can get a very funny - musty/rotting smell from overheated plastic
light fittings.

I spent several months trying to track down the source of a
damp/rotting smell in my extension which came and went , before
discovering the slightly brown bayonet light fittings.

Robert
Robert

Phil L wrote:
John Kelly wrote:
Phil L wrote:

Newbuild should also have crossflow ventilation in roof spaces,
usually a soffit vent running the full length of the fascia board
and airbricks in the walls or ridge vents on the roof..what may have
happened here is that they have blocked the effectiveness of the
soffit vent with insulation pushed too tightly against the joist
ends.

The fascia board is solid. No airbricks either from what I can make
out. The building inspector person seemed perfectly happy with it all
when he came round.

'Breathable' undefelt is *not* sufficient on it's own, I'm surprised the
plans were passed or the BCO let this go like this.

According to the BBA it can be, depending on the design and
construction of the roof. See he

http://www.bbacerts.co.uk/pdf/brtu.p...rane%20roof%22

Certainly, our new roof has no additional ventilation - our builder
appeared to be under the impression that this was very common practice
these days.

Jon.

"Tournifreak" wrote in message
ups.com...

Phil L wrote:
John Kelly wrote:
Phil L wrote:

Newbuild should also have crossflow ventilation in roof spaces,
usually a soffit vent running the full length of the fascia board
and airbricks in the walls or ridge vents on the roof..what may have
happened here is that they have blocked the effectiveness of the
soffit vent with insulation pushed too tightly against the joist
ends.

The fascia board is solid. No airbricks either from what I can make
out. The building inspector person seemed perfectly happy with it all
when he came round.

'Breathable' undefelt is *not* sufficient on it's own, I'm surprised the
plans were passed or the BCO let this go like this.

According to the BBA it can be, depending on the design and
construction of the roof. See he

http://www.bbacerts.co.uk/pdf/brtu.p...rane%20roof%22

Certainly, our new roof has no additional ventilation - our builder
appeared to be under the impression that this was very common practice
these days.


It is, we have just (2002) had an (excellently constructed) extension
finished. Breathable membrane was on the approved plans and passed on the
building with no additional ventilation.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

Bob Mannix wrote:
"Tournifreak" wrote in message
ups.com...
Phil L wrote:
John Kelly wrote:
Phil L wrote:
Newbuild should also have crossflow ventilation in roof spaces,
usually a soffit vent running the full length of the fascia board
and airbricks in the walls or ridge vents on the roof..what may have
happened here is that they have blocked the effectiveness of the
soffit vent with insulation pushed too tightly against the joist
ends.
The fascia board is solid. No airbricks either from what I can make
out. The building inspector person seemed perfectly happy with it all
when he came round.
'Breathable' undefelt is *not* sufficient on it's own, I'm surprised the
plans were passed or the BCO let this go like this.
According to the BBA it can be, depending on the design and
construction of the roof. See he

http://www.bbacerts.co.uk/pdf/brtu.p...rane%20roof%22

Certainly, our new roof has no additional ventilation - our builder
appeared to be under the impression that this was very common practice
these days.

It is, we have just (2002) had an (excellently constructed) extension
finished. Breathable membrane was on the approved plans and passed on the
building with no additional ventilation.

Thanks for confirming that it's okay in that respect. I was getting a
little worried...

Since sunday morning (the rain stopped) it's been absolutely fine.
Smells perfectly normal in there now.

--
John Kelly

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replying to robert, IpsoFatto wrote:
Hi,
I hope you don't mind me reactivating this thread - I just came across it and
@John Kelly's issue describes exactly a problem we're having with a garage
extension we had done. Â*I wonder if you might be able to tell me if you were
able to resolve this and if so, how?Any advice would be much appreciated -
we're at hte point of considering a surveyor to come around and do an
investigation as the smell in humid weather is so strong, while the rest of
the time, there is absolutely no smell at all. Â*It's very odd. Grateful for
any advice!

--
for full context, visit https://www.homeownershub.com/uk-diy...se-280186-.htm

On Friday, 7 August 2020 01:44:05 UTC+1, IpsoFatto wrote:
replying to robert, IpsoFatto wrote:
Hi,
I hope you don't mind me reactivating this thread - I just came across it and
@John Kelly's issue describes exactly a problem we're having with a garage
extension we had done. Â*I wonder if you might be able to tell me if you were
able to resolve this and if so, how?Any advice would be much appreciated -
we're at hte point of considering a surveyor to come around and do an
investigation as the smell in humid weather is so strong, while the rest of
the time, there is absolutely no smell at all. Â*It's very odd. Grateful for
any advice!

You should find online diagrams of all the usual sources of water. Just check for them.


NT

Were any pipes or inspection covers etc, moved when it was built to allow
them to still be accessed. However the only in humid weather sounds more
like a leak that will not dry due to the high humidity periods. Could be
some kind of organism is present.
Brian

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This newsgroup posting comes to you directly from...
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Note this Signature is meaningless.!
wrote in message
...
On Friday, 7 August 2020 01:44:05 UTC+1, IpsoFatto wrote:
replying to robert, IpsoFatto wrote:
Hi,
I hope you don't mind me reactivating this thread - I just came across it
and
@John Kelly's issue describes exactly a problem we're having with a garage
extension we had done. I wonder if you might be able to tell me if you
were
able to resolve this and if so, how?Any advice would be much appreciated -
we're at hte point of considering a surveyor to come around and do an
investigation as the smell in humid weather is so strong, while the rest
of
the time, there is absolutely no smell at all. It's very odd. Grateful
for
any advice!

You should find online diagrams of all the usual sources of water. Just
check for them.


NT

On Saturday, 2 September 2006 16:47:18 UTC+1, John Kelly wrote:
Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather
(like we have at the moment). There's no obvious signs of damp around
the walls or floor and everything seems dry. The room is shaded with a
large hedge running to the side of it (if this makes any difference).
What could cause this problem and what can we do about it? It's not very
pleasant to be in the room.


Probably just the smell of new plaster and cement.
Get yourself a de-humidifier. It'll probably fix the problem in a few days.

It must be run with all the windows and doors shut.

On Saturday, 8 August 2020 08:18:23 UTC+1, harry wrote:
On Saturday, 2 September 2006 16:47:18 UTC+1, John Kelly wrote:

Our home had an extension built earlier this year. The extension was to
the side of the house and involved knocking through. After 7 months the
room smells damp or musty and seems particularly bad in damp weather
(like we have at the moment). There's no obvious signs of damp around
the walls or floor and everything seems dry. The room is shaded with a
large hedge running to the side of it (if this makes any difference).
What could cause this problem and what can we do about it? It's not very
pleasant to be in the room.


Probably just the smell of new plaster and cement.
Get yourself a de-humidifier. It'll probably fix the problem in a few days.

It must be run with all the windows and doors shut.

pointless in this weather!


NT