I have recently insulated under the timber floor (has a void about
18").,
with slab polystyrene. (was free, and the sort used in flat roof
insulation).
The stuff was cut to fit the joists and is pressed down onto tanalised
battens.
Battens are roof lathes and the polystyrene is 50mm.
Extra to this is cooking foil pasted onto the surface This cost less
than £2 for the whole room.
.. An attempt to duplicate
aka Kingspan. No vapour barrier other than the foil and not over the
joists.On top is new
chipboard flooring.
My question to you luvverly people is...IS THIS SAFE. Have I got to
undo.

Polystyrene - fire safety - toxic fumes, bad news.
Polystyrene - contact with pvc insulated wiring - hardening and
cracking of insulation.

I think if your floors ablaze, the polystyrene fumes are the least of
your worries;-)

good point about the PVC tho


wrote:
Polystyrene - fire safety - toxic fumes, bad news.
Polystyrene - contact with pvc insulated wiring - hardening and
cracking of insulation.

Thank you for the replies, not sure whether to post at top or bottom.
However, had the idea that the foil would delay spread of flames and
flames would burn away from it anyway.
Flooring is screwed down so not a big job to dismantle. Could have
sworn Kingspan was Polystyrene with added foil, and is recommended for
under floor. Also I notice Wickes sell Polystyrene for the same
purpose.
Is consulting the Local Authority Building Inspector FREE.??



wrote:

I think if your floors ablaze, the polystyrene fumes are the least of
your worries;-)

good point about the PVC tho


wrote:
Polystyrene - fire safety - toxic fumes, bad news.
Polystyrene - contact with pvc insulated wiring - hardening and
cracking of insulation.

"ken70" wrote in message
ups.com...

Could have
sworn Kingspan was Polystyrene with added foil,

Kingspan is polyurethane

--
Mike W

On 21 Dec 2006 07:09:07 -0800 Ken70 wrote :
Could have sworn
Kingspan was Polystyrene with added foil, and is recommended for
under floor. Also I notice Wickes sell Polystyrene for the same
purpose.

Most Kingspan/Celotex boards are polyurethane which is a much
better insulator - 25mm PU is as good as or better than 40mm EPS

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk

ken70 wrote:

I have recently insulated under the timber floor (has a void about
18").,
with slab polystyrene. (was free, and the sort used in flat roof
insulation).
The stuff was cut to fit the joists and is pressed down onto tanalised
battens.
Battens are roof lathes and the polystyrene is 50mm.
Extra to this is cooking foil pasted onto the surface This cost less
than £2 for the whole room.
. An attempt to duplicate
aka Kingspan. No vapour barrier other than the foil and not over the
joists.On top is new
chipboard flooring.
My question to you luvverly people is...IS THIS SAFE. Have I got to
undo.

If it is flooring grade insulation then chances are it is treated with a
flame retardent anyway. So it will melt if you heat it enough, but ought
not add to the spread of flames. So if you keepo it out of contact with
any PVC it ought to be ok.

Note that kingspan etc are not the same - they are Polyisocyanurate
(PIR) foam.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

ken70 wrote:
Thank you for the replies, not sure whether to post at top or bottom.
However, had the idea that the foil would delay spread of flames and
flames would burn away from it anyway.
Flooring is screwed down so not a big job to dismantle. Could have
sworn Kingspan was Polystyrene with added foil

No. It's foam with added foil, and twice the price of polystyrene.
Presumably it smells sweeter when ablaze.

, and is recommended for
under floor. Also I notice Wickes sell Polystyrene for the same
purpose.
Is consulting the Local Authority Building Inspector FREE.??



wrote:

I think if your floors ablaze, the polystyrene fumes are the least of
your worries;-)

good point about the PVC tho


wrote:
Polystyrene - fire safety - toxic fumes, bad news.
Polystyrene - contact with pvc insulated wiring - hardening and
cracking of insulation.

On Thu, 21 Dec 2006 07:09:07 -0800, ken70 wrote:

Thank you for the replies, not sure whether to post at top or bottom.
However, had the idea that the foil would delay spread of flames and
flames would burn away from it anyway. Flooring is screwed down so not a
big job to dismantle. Could have sworn Kingspan was Polystyrene with added
foil, and is recommended for under floor. Also I notice Wickes sell
Polystyrene for the same purpose.
Is consulting the Local Authority Building Inspector FREE.??



snipped

================================
I did this same job about three years ago except that I used just the
polystyrene without foil. I asked my local BCO about suitability and he
said there were no problems with using polystyrene in this way.

I was aware from posts elsewhere that PVC wiring and polystyrene was a bad
mix so I made sure that the wiring runs were kept separate from the
polystyrene. As far as fire risk is concerned I don't think I've ever
heard of a fire starting under a suspended floor so I think the risk must
be quite minimal.

Cic.

--
================================
Testing UBUNTU Linux
Everything working so far
================================

Stuart Noble wrote:

No. It's foam with added foil, and twice the price of polystyrene.
Presumably it smells sweeter when ablaze.

It doesn't burn _very_ well, but it does catch fire.
So I found out when using some of it to protect the walls whilst
chopping some 1/4" plate with an angle grinder in-situ in the lounge.

:¬)

--
http://gymratz.co.uk - Best Gym Equipment & Bodybuilding Supplements UK.
http://gymratz.co.uk/polar-heart-rate-monitors/ Polar HeartRate Monitors
http://fitness-equipment-uk.com - UK's No.1 Fitness Equipment Suppliers.
http://water-rower.co.uk - Worlds best prices on the Worlds best Rower.

In article ,
Stuart Noble writes:
ken70 wrote:
Thank you for the replies, not sure whether to post at top or bottom.
However, had the idea that the foil would delay spread of flames and
flames would burn away from it anyway.
Flooring is screwed down so not a big job to dismantle. Could have
sworn Kingspan was Polystyrene with added foil

No. It's foam with added foil, and twice the price of polystyrene.
Presumably it smells sweeter when ablaze.

One of its combusion products is cyanide, although I doubt you
would be able to smell the almonds amongst the other things.
You can smell it when you cut the sheets with a knife (it's
probably a more complex cyanide-based molecule in this case).

Combusion products of polystyrene are pretty nasty too because
it does a bad job of burning all the products, and you end up
with significant amounts of unburned styrene, carbon monoxide,
benzene, toluene, etc coming off. If it's old polystyrene, you
also get combustion products from the incomplete burning of the
CFC used to expand it, which can include hydrogen fluoride.

--
Andrew Gabriel

Only cables are from defunct E7 system, disconnected at both ends, and
laid flat on the void concrete 'floor'.The polystyrene was free from a
retired flat roof specialist, so is probably treated.
Will see the BCO in the New Year, one option being to add gypsum board,
tho barely room for this.......... Muchass Grassiuss.

Andrew Gabriel wrote:

In article ,
Stuart Noble writes:
ken70 wrote:
Thank you for the replies, not sure whether to post at top or bottom.
However, had the idea that the foil would delay spread of flames and
flames would burn away from it anyway.
Flooring is screwed down so not a big job to dismantle. Could have
sworn Kingspan was Polystyrene with added foil

No. It's foam with added foil, and twice the price of polystyrene.
Presumably it smells sweeter when ablaze.

One of its combusion products is cyanide, although I doubt you
would be able to smell the almonds amongst the other things.
You can smell it when you cut the sheets with a knife (it's
probably a more complex cyanide-based molecule in this case).

Combusion products of polystyrene are pretty nasty too because
it does a bad job of burning all the products, and you end up
with significant amounts of unburned styrene, carbon monoxide,
benzene, toluene, etc coming off. If it's old polystyrene, you
also get combustion products from the incomplete burning of the
CFC used to expand it, which can include hydrogen fluoride.

--
Andrew Gabriel

On 21 Dec 2006 04:06:05 -0800, a particular chimpanzee named "ken70"
randomly hit the keyboard and produced:

I have recently insulated under the timber floor (has a void about
18").,
with slab polystyrene. (was free, and the sort used in flat roof
insulation)....

My question to you luvverly people is...IS THIS SAFE. Have I got to
undo.

http://www.vencel.co.uk/products/ins...oors&nav=nav_1
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

Thank you Hugo...lots to read....think I'm covered but checking with
County Hall after the holiday.
If not O.K'd cheapest way out would to paint on some flame retardent.
Got the original info from a 'Which' DIY book (published 1999), should
have come here first. :-)


Hugo Nebula wrote:

On 21 Dec 2006 04:06:05 -0800, a particular chimpanzee named "ken70"
randomly hit the keyboard and produced:

I have recently insulated under the timber floor (has a void about
18").,
with slab polystyrene. (was free, and the sort used in flat roof
insulation)....

My question to you luvverly people is...IS THIS SAFE. Have I got to
undo.

http://www.vencel.co.uk/products/ins...oors&nav=nav_1
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"