Apologies if this has been done to death but I would be grateful for
another opinion.

My 1930s house (no cavity walls, no felt under roof tiles) has about
100mm of oldish loft insulation (fibreglass I think - don't know how
old). Currently little of the loft is boarded and what is, is not really
usable.

I need to board a fair percentage of the loft for storage purposes.

What I am wondering is whether it is worth getting the loft reinsulated
before I board. As the new guidelines specify 250mm or so of insulation
depth I would have the problem of losing my joists for attaching the
boards to.

Should I leave the insulation as it is and just put my boards down.
Saving the £199[*] it will cost to reinsulate?

or

Should I reinsulate fully then negotiate (ie remove) the insulation
where I need to board?

or

Should I look for another insulation material to go under the boards
that won't rise above the joists?

At present, my instinct tells me to leave it as it is. Though maybe add
a little more insulation around the edges. Will what I store in the loft
help insulate?

It seems that good loft insulation and using the loft as storage space
don't necessarily go hand in hand.

Thanks, Dan

[* - A flat fee I have been quoted]

danw wrote:

What I am wondering is whether it is worth getting the loft reinsulated
before I board. As the new guidelines specify 250mm or so of insulation
depth I would have the problem of losing my joists for attaching the
boards to.

Should I leave the insulation as it is and just put my boards down.
Saving the £199[*] it will cost to reinsulate?

Possibly. I did this, though, before realising that my insulation is
probably inadequate, and now I regret it.

Should I reinsulate fully then negotiate (ie remove) the insulation
where I need to board?

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it away
from the joists into the gaps, and then pressing the boards down on top,
makes the whole lot a waste.

Should I look for another insulation material to go under the boards
that won't rise above the joists?

That's a possibility, though the material will almost certainly be more
expensive.

Will what I store in the loft help insulate?

Not to any real extent, unless you're storing loft insulation :-).


Another option might be to extend the joists upwards, by putting another
timber strip on top. Don't rely on these for added strength without some
serious thought (though they'd probably add some if well-fixed to the
joists) but they'd put your boards higher up with room for more insulation.

Pete

Pete Verdon wrote:
danw wrote:

What I am wondering is whether it is worth getting the loft
reinsulated before I board. As the new guidelines specify 250mm or
so of insulation depth I would have the problem of losing my joists
for attaching the boards to.

Should I leave the insulation as it is and just put my boards down.
Saving the £199[*] it will cost to reinsulate?

Possibly. I did this, though, before realising that my insulation is
probably inadequate, and now I regret it.

Should I reinsulate fully then negotiate (ie remove) the insulation
where I need to board?

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it
away from the joists into the gaps, and then pressing the boards down
on top, makes the whole lot a waste.


It doesn't....200mm of insulation squashed down to 100mm still has a lot
more insulating properties than 100mm


To the OP: add another 70 or 80mm of insulation (you can use any kind of
fibreglass for this, cavity batts will suffice and they are availible in
these thicknesses) and then board over.

Add another 200mm to the remainder of the loft if you feel like it

Phil L wrote:
Pete Verdon wrote:

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it
away from the joists into the gaps, and then pressing the boards down
on top, makes the whole lot a waste.

It doesn't....200mm of insulation squashed down to 100mm still has a lot
more insulating properties than 100mm

Really? I was under the impression that the purpose of the insulation
was simply to hold air in one place, with the actual inhibition of heat
transfer provided by the air. After all, glass isn't a particularly good
insulator (cold window-panes?) itself.

Pete

Pete Verdon wrote:
Phil L wrote:
Pete Verdon wrote:

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it
away from the joists into the gaps, and then pressing the boards
down on top, makes the whole lot a waste.

It doesn't....200mm of insulation squashed down to 100mm still has a
lot more insulating properties than 100mm

Really? I was under the impression that the purpose of the insulation
was simply to hold air in one place, with the actual inhibition of
heat transfer provided by the air. After all, glass isn't a
particularly good insulator (cold window-panes?) itself.

Pete

That's what I thought too, but we had to visit the factory where it's made
(which is incidentally only a mile away from where I live) when we were
installing CWI...the factory makes all kinds of insulation and on this
particular day, a FG mat was coming off the conveyor belt which must have
been easily 500mm thick, and it went through a compressing machine which
spat out rigid boards at the other side.
I mentioned about the air being the insulant and was informed that the FG
would retain '70 to 80% of it's original insulating properties'...this meant
that the boards, which were about 40mm, had the insulation properties of at
least 300mm matting

Phil L wrote:
Pete Verdon wrote:
Phil L wrote:
Pete Verdon wrote:

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it
away from the joists into the gaps, and then pressing the boards
down on top, makes the whole lot a waste.

It doesn't....200mm of insulation squashed down to 100mm still has a
lot more insulating properties than 100mm

Really? I was under the impression that the purpose of the insulation
was simply to hold air in one place, with the actual inhibition of
heat transfer provided by the air. After all, glass isn't a
particularly good insulator (cold window-panes?) itself.

Pete

That's what I thought too, but we had to visit the factory where it's
made (which is incidentally only a mile away from where I live) when
we were installing CWI...the factory makes all kinds of insulation
and on this particular day, a FG mat was coming off the conveyor belt
which must have been easily 500mm thick, and it went through a
compressing machine which spat out rigid boards at the other side.
I mentioned about the air being the insulant and was informed that
the FG would retain '70 to 80% of it's original insulating
properties'...this meant that the boards, which were about 40mm, had
the insulation properties of at least 300mm matting

I guess 18mm chipboard must have some insulating properties anyway?



--
Dave - The Medway Handyman
www.medwayhandyman.co.uk
01634 717930
07850 597257

danw wrote:
Apologies if this has been done to death but I would be grateful for
another opinion.

My 1930s house (no cavity walls, no felt under roof tiles) has about
100mm of oldish loft insulation (fibreglass I think - don't know how
old). Currently little of the loft is boarded and what is, is not really
usable.

I need to board a fair percentage of the loft for storage purposes.

What I am wondering is whether it is worth getting the loft reinsulated
before I board. As the new guidelines specify 250mm or so of insulation
depth I would have the problem of losing my joists for attaching the
boards to.

Should I leave the insulation as it is and just put my boards down.
Saving the £199[*] it will cost to reinsulate?

or

Should I reinsulate fully then negotiate (ie remove) the insulation
where I need to board?

or

Should I look for another insulation material to go under the boards
that won't rise above the joists?

At present, my instinct tells me to leave it as it is. Though maybe add
a little more insulation around the edges. Will what I store in the loft
help insulate?

It seems that good loft insulation and using the loft as storage space
don't necessarily go hand in hand.

Thanks, Dan

[* - A flat fee I have been quoted]

At current fuel prices I'd go celotex and FULL boarding. Floor grade chip.

Pete Verdon wrote:
danw wrote:

What I am wondering is whether it is worth getting the loft
reinsulated before I board. As the new guidelines specify 250mm or so
of insulation depth I would have the problem of losing my joists for
attaching the boards to.

Should I leave the insulation as it is and just put my boards down.
Saving the £199[*] it will cost to reinsulate?

Possibly. I did this, though, before realising that my insulation is
probably inadequate, and now I regret it.

Should I reinsulate fully then negotiate (ie remove) the insulation
where I need to board?

I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it away
from the joists into the gaps, and then pressing the boards down on top,
makes the whole lot a waste.

Should I look for another insulation material to go under the boards
that won't rise above the joists?

That's a possibility, though the material will almost certainly be more
expensive.

Will what I store in the loft help insulate?

Not to any real extent, unless you're storing loft insulation :-).


You would be surpised.

I have found te UFH floor under the sofa to be some 4-5 C warmer tha te
floor that just has a rug on it..inference being the sofa is doing some
insulation.

Piles of old newpaperes probably are as good as 60mm celotex.


Another option might be to extend the joists upwards, by putting another
timber strip on top. Don't rely on these for added strength without some
serious thought (though they'd probably add some if well-fixed to the
joists) but they'd put your boards higher up with room for more insulation.

Pete

On Fri, 22 Feb 2008 16:57:46 GMT, "Phil L"
wrote:


I don't see how this would help. Squashing 200mm of insulation into
100mm of space gives it the effectiveness of 100mm. So sweeping it
away from the joists into the gaps, and then pressing the boards down
on top, makes the whole lot a waste.


It doesn't....200mm of insulation squashed down to 100mm still has a lot
more insulating properties than 100mm


To the OP: add another 70 or 80mm of insulation (you can use any kind of
fibreglass for this, cavity batts will suffice and they are availible in
these thicknesses) and then board over.

And there's no undue pressure on the ceiling below?


Add another 200mm to the remainder of the loft if you feel like it

--
http://www.orderonlinepickupinstore.co.uk
Ah fetch it yourself if you can't wait for delivery
http://www.freedeliveryuk.co.uk
Or get it delivered for free

"danw" wrote in message
...
Apologies if this has been done to death but I would be grateful for
another opinion.

My 1930s house (no cavity walls, no felt under roof tiles) has about 100mm
of oldish loft insulation (fibreglass I think - don't know how old).
Currently little of the loft is boarded and what is, is not really usable.

I need to board a fair percentage of the loft for storage purposes.

What I am wondering is whether it is worth getting the loft reinsulated
before I board. As the new guidelines specify 250mm or so of insulation
depth I would have the problem of losing my joists for attaching the
boards to.

Should I leave the insulation as it is and just put my boards down. Saving
the £199[*] it will cost to reinsulate?

or

Should I reinsulate fully then negotiate (ie remove) the insulation where
I need to board?

or

Should I look for another insulation material to go under the boards that
won't rise above the joists?

At present, my instinct tells me to leave it as it is. Though maybe add a
little more insulation around the edges. Will what I store in the loft
help insulate?

It seems that good loft insulation and using the loft as storage space
don't necessarily go hand in hand.

Thanks, Dan

[* - A flat fee I have been quoted]

Fill between the joists with rockwool, or what you already have. Then put
over the joists rigid foam insulation. Over that chipboard. Screw right
through the chipboard and foam. Thos eliminated cold bridging.

Seal with silicon all holes in the ceiling and fit an insulated sealed
hatch.

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.

Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

On Sat, 23 Feb 2008 01:25:44 +0000, The Natural Philosopher
wrote:

Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

That's because they contain a lot of 'hot air'!

"The Natural Philosopher" wrote in message
...
Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

Figures please?

In article ,
Edward W. Thompson wrote:

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

That's because they contain a lot of 'hot air'!

:-D Outstanding.


A foot of newspapers weighs an _awful_ lot! My neighbour's roof
(outside) has discernible dips in it: he was told by an architect friend
that this was because he's got so much crap stored here there and
everywhere in his loft (carpets, furniture, etc.), and the weight is
dragging on the roof trusses.

danw wrote:
Apologies if this has been done to death but I would be grateful for
another opinion.

Thanks for all the replies. If I were to buy something such as Celotex
where should I go for it? And should I stick to 90mm?

Thanks, Dan

"The Natural Philosopher" wrote in message
...
Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

Figures please.

Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...
Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

Figures please.

Would you understand them If I wrote them?


You never have before.

"The Natural Philosopher" wrote in message
...
Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...
Doctor Drivel wrote:

"The Natural Philosopher" wrote in message
...

Piles of old newpaperes probably are as good as 60mm celotex.

You made that up. And what a fire hazzard.


Not as much as your polystyrene.

Newspapers are surprisingly good insulators.

A foot of newspaper is - if dry - a substantial layer.

Figures please.

Would you understand them If I wrote them?

Not with your crayon.