Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to take
the pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are
9" deep and Rockwool 6". Perhaps lengths of plain galvanised fencing
wire stapled between the joists? Any impact on wi-fi transmission?


--
Tim Lamb

"Tim Lamb" wrote in message
...

Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the job
done! Ground floor no real problems: grooved insulated sheet to take the
pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and particularly
not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both systems
call for insulation between the joists and in contact with the underside of
the floor. PIR foam is not cheap, needs careful cutting/fitting together
with supporting battens. Rockwool is cheaper and easy to cut and fit
but... how do you stop it ending up resting on the ceiling plaster board,
light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are 9"
deep and Rockwool 6". Perhaps lengths of plain galvanised fencing wire
stapled between the joists? Any impact on wi-fi transmission?




When we did up the house and holiday cottages, I bought rolls of garden type
green nylon netting off ebay, and stapled it to the joists, laying
insulation batts suspended by it.

Andrew

On 12/6/2016 10:37 PM, Andrew Mawson wrote:
"Tim Lamb" wrote in message
...

Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to
take the pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing.
The dormer cheeks are double or triple timbered and the intervening
space filled with ladder work on joist hangers. Elsewhere walls have
double supporting timbers.

I have been considering cross battens but this adds a huge cost and
the suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists
are 9" deep and Rockwool 6". Perhaps lengths of plain galvanised
fencing wire stapled between the joists? Any impact on wi-fi
transmission?




When we did up the house and holiday cottages, I bought rolls of garden
type green nylon netting off ebay, and stapled it to the joists, laying
insulation batts suspended by it.

Andrew


I was going to suggest string rather than wire, but I like that idea
even more.

Yes I've seen that orange netting often used around peoples new driveways
for stopping public walking on wet cement. Tat stuff is used by construction
companies by the roll and then tossed away cos its cheap, Used indoors it
should last for ages.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Andrew Mawson" wrote in message
news
"Tim Lamb" wrote in message
...

Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the job
done! Ground floor no real problems: grooved insulated sheet to take the
pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and particularly
not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both systems
call for insulation between the joists and in contact with the underside
of the floor. PIR foam is not cheap, needs careful cutting/fitting
together with supporting battens. Rockwool is cheaper and easy to cut and
fit but... how do you stop it ending up resting on the ceiling plaster
board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are
9" deep and Rockwool 6". Perhaps lengths of plain galvanised fencing wire
stapled between the joists? Any impact on wi-fi transmission?




When we did up the house and holiday cottages, I bought rolls of garden
type green nylon netting off ebay, and stapled it to the joists, laying
insulation batts suspended by it.

Andrew

On Tuesday, 6 December 2016 22:26:03 UTC, Tim Lamb wrote:
Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to take
the pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are
9" deep and Rockwool 6". Perhaps lengths of plain galvanised fencing
wire stapled between the joists? Any impact on wi-fi transmission?


--
Tim Lamb

Rigid foam bats can be bought far more cheaply as "seconds".
(Minor damage)
Just Google "insulation boards seconds" to find some local toyou.

In message ,
newshound writes
On 12/6/2016 10:37 PM, Andrew Mawson wrote:
"Tim Lamb" wrote in message
...

Insulation between joists below under floor heating.



When we did up the house and holiday cottages, I bought rolls of garden
type green nylon netting off ebay, and stapled it to the joists, laying
insulation batts suspended by it.

Andrew


I was going to suggest string rather than wire, but I like that idea
even more.

OK chaps. Several ideas to investigate there.

The green nylon garden netting with wide spacing for Pea and Bean
supports is not UV stable but I guess that is not a problem between
floors.

Staples with soft wire zig zag? Easy to do in modest lengths.

Seconds PIR I had not considered but it would need to be hugely cheaper
as I estimate 150mm Rockwool is around a quarter the cost of 75mm foam.
And there is still the cutting plus support battens.

I suppose one has to consider fire risks and any impact on through
ceiling mounted light fittings.

Architect site meeting tomorrow. I'll run this by him.

Thanks

--
Tim Lamb

On Tue, 6 Dec 2016 22:25:53 +0000, Tim Lamb
wrote:

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

The upstairs under floor heating here has the heating pipes clipped in
thin aluminium sheets to act as heat spreaders. The heat spreaders
were cut to fit odd shapes. Insulation is fibreglass laid below them.
The flooring chipboard is fixed on top.

Upstairs under floor heating is generally much less critical than
downstairs as the downstairs heat rises and (assuming a well insulated
house) keeps the upper floor at a constant and slightly lower
temperature than downstairs even with no upstairs heating.

On Wednesday, 7 December 2016 09:56:52 UTC, Peter Parry wrote:
On Tue, 6 Dec 2016 22:25:53 +0000, Tim Lamb
wrote:

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

The upstairs under floor heating here has the heating pipes clipped in
thin aluminium sheets to act as heat spreaders. The heat spreaders
were cut to fit odd shapes. Insulation is fibreglass laid below them.
The flooring chipboard is fixed on top.

Upstairs under floor heating is generally much less critical than
downstairs as the downstairs heat rises and (assuming a well insulated
house) keeps the upper floor at a constant and slightly lower
temperature than downstairs even with no upstairs heating.

I'm struggling to see the point of much underfloor insulation upstairs. Upstairs UFH will add a limited amount of heat to downstairs, and downstairs UFH compensates accordingly.


NT

Tim Lamb explained :
? Any impact on wi-fi transmission?

It will block, or severally reduce the range.

On Wed, 7 Dec 2016 02:44:28 -0800 (PST), wrote:


I'm struggling to see the point of much underfloor insulation upstairs. Upstairs UFH will add a limited amount of heat to downstairs, and downstairs UFH compensates accordingly.

I agree, I suspect ours was added because the instructions said so
(it was 25 years ago).

In message , Peter Parry
writes
On Wed, 7 Dec 2016 02:44:28 -0800 (PST), wrote:


I'm struggling to see the point of much underfloor insulation
upstairs. Upstairs UFH will add a limited amount of heat to
downstairs, and downstairs UFH compensates accordingly.

I agree, I suspect ours was added because the instructions said so
(it was 25 years ago).

Could be:-)

There is also the issue of de-rating electrical wiring run through
insulation to say nothing of elevated temperatures in the void. Perhaps
a supplementary query for the electricians.

I have been following the LED thread but not learned much yet:-)

Looking at the thermal finning on some recessed LED fittings, I rather
wonder if surface mount might be better.



--
Tim Lamb

In message , Harry Bloomfield
writes
Tim Lamb explained :
? Any impact on wi-fi transmission?

It will block, or severally reduce the range.

There is always Devolo as I don't know of any radio hams within 400m.

--
Tim Lamb

On 06/12/2016 22:37, Andrew Mawson wrote:

When we did up the house and holiday cottages, I bought rolls of garden
type green nylon netting off ebay, and stapled it to the joists, laying
insulation batts suspended by it.

Andrew

I did similar ... just put the aluminium reflector foil under the pipes
(industrial bacofoil) then 150mm rockwool pressed in place .. and used
a lattice of nylon cord zig zagging from joist to joist ... stapling in
place on the joists.

By having rockwool slightly oversize it self supported itself ... cord
just stops sag over time.

Tim Lamb wrote:
Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to
take the pipes covered with standard chipboard or screed for the new
bit.
Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing.
The dormer cheeks are double or triple timbered and the intervening
space filled with ladder work on joist hangers. Elsewhere walls have
double supporting timbers.

I have been considering cross battens but this adds a huge cost and
the suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists
are 9" deep and Rockwool 6". Perhaps lengths of plain galvanised
fencing wire stapled between the joists? Any impact on wi-fi
transmission?

Insulation isn't needed for upstairs floors, any heat 'lost' isn't actually
lost - it's just transferred downstairs into the living space which will
reduce the amount of power required to heat that space.

In message , Phil L
writes
Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists
are 9" deep and Rockwool 6". Perhaps lengths of plain galvanised
fencing wire stapled between the joists? Any impact on wi-fi
transmission?

Insulation isn't needed for upstairs floors, any heat 'lost' isn't actually
lost - it's just transferred downstairs into the living space which will
reduce the amount of power required to heat that space.

You are right of course but I think this is more to do with heat
management in local zones. Not much point in having individual roomstats
if the whole house is thermally linked.




--
Tim Lamb

On Tue, 06 Dec 2016 22:25:53 +0000, Tim Lamb wrote:

Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to take
the pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are
9" deep and Rockwool 6". Perhaps lengths of plain galvanised fencing
wire stapled between the joists? Any impact on wi-fi transmission?

How about fibreglass inside a plastic sleeve - as used for insulation
everywhere?

The sleeve holds it together so it doesn't need very much support.

Not much good in your case, but if insulating a ceiling above plaster
board it is very easy to staple the plastic to the joists which holds it
in place until you get the plasterboard up.

String or netting stapled below the insulation should work well. Doesn't
have to be very robust with squishy fibreglass rolls.

Cheers


Dave R



--
AMD FX-6300 in GA-990X-Gaming SLI-CF running Windows 7 Pro x64

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

In message , David
writes
On Tue, 06 Dec 2016 22:25:53 +0000, Tim Lamb wrote:

Insulation between joists below under floor heating.

Having promised no wall hung radiators I am now stuck with getting the
job done! Ground floor no real problems: grooved insulated sheet to take
the pipes covered with standard chipboard or screed for the new bit.

Upstairs life gets expensive and difficult. All the suppliers call for
insulation below and in contact with the heated floor. In a chalet
bungalow, there is no such thing as a standard floor joist spacing. The
dormer cheeks are double or triple timbered and the intervening space
filled with ladder work on joist hangers. Elsewhere walls have double
supporting timbers.

I have been considering cross battens but this adds a huge cost and the
suggested sizes (30mm x 70mm) are not found off the shelf and
particularly not untreated.

Pre-grooved chipboard is an alternative and cheaper solution. Both
systems call for insulation between the joists and in contact with the
underside of the floor. PIR foam is not cheap, needs careful
cutting/fitting together with supporting battens. Rockwool is cheaper
and easy to cut and fit but... how do you stop it ending up resting on
the ceiling plaster board, light fittings and electrical wiring?

Chicken wire netting? Some sort of cross batten or?? My floor joists are
9" deep and Rockwool 6". Perhaps lengths of plain galvanised fencing
wire stapled between the joists? Any impact on wi-fi transmission?

How about fibreglass inside a plastic sleeve - as used for insulation
everywhere?

The sleeve holds it together so it doesn't need very much support.

Not much good in your case, but if insulating a ceiling above plaster
board it is very easy to staple the plastic to the joists which holds it
in place until you get the plasterboard up.

String or netting stapled below the insulation should work well. Doesn't
have to be very robust with squishy fibreglass rolls.

I'm going with the garden netting stapled to the joists.

Interesting conversation with the architect concerning fire protection.
Apparently 12mm plasterboard has only a 20 minute rating. I asked if the
glass fibre would stretch this to the required 30 minutes and avoid the
need to add 9mm board over the existing.

He thought it might be worth running by building control but reckoned
that the 9" joists might be good for the extra time anyway.

Cheers


Dave R




--
Tim Lamb