Installing the underfloor heating has neared the top of the jobs list.

Despite much reading of suppliers PDFs and head scratching there are
still areas of uncertainty:-)

Current thinking for the screeded area is to use self adhesive clip
rails over the Celotex foam. Spacing between rows seem to vary from
750mm to 2.0m depending on source.
Question for the chemists... what is the surface coating on the
aluminium foil? Cleans off readily with acetone and accepts the supplied
tape readily but *duct tape* needs it cleaned off first.

Floor heating suppliers provide a thin foam perimeter sheet to provide
expansion space for the screed but Celotex show an upstand of PIR foam
to insulate perimeter walls. Do I use both?

There may be more to follow...
--
Tim Lamb

On 30/07/2017 10:17, Tim Lamb wrote:
Installing the underfloor heating has neared the top of the jobs list.

Despite much reading of suppliers PDFs and head scratching there are
still areas of uncertainty:-)

Current thinking for the screeded area is to use self adhesive clip
rails over the Celotex foam. Spacing between rows seem to vary from
750mm to 2.0m depending on source.

Have you looked at the staple fixing options? You can get a long arm
device that sticks staples into the floor (without needing to bend etc)
to hold the pipes in place.

Question for the chemists... what is the surface coating on the
aluminium foil? Cleans off readily with acetone and accepts the supplied
tape readily but *duct tape* needs it cleaned off first.

Floor heating suppliers provide a thin foam perimeter sheet to provide
expansion space for the screed but Celotex show an upstand of PIR foam
to insulate perimeter walls. Do I use both?

How resilient is the foam they suggest?

(there is some, but not much give in PIR foam when the load is
distributed over a wide area)


--
Cheers,

John.

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

In message , John
Rumm writes
On 30/07/2017 10:17, Tim Lamb wrote:
Installing the underfloor heating has neared the top of the jobs list.

Despite much reading of suppliers PDFs and head scratching there are
still areas of uncertainty:-)

Current thinking for the screeded area is to use self adhesive clip
rails over the Celotex foam. Spacing between rows seem to vary from
750mm to 2.0m depending on source.

Have you looked at the staple fixing options? You can get a long arm
device that sticks staples into the floor (without needing to bend etc)
to hold the pipes in place.

Yes. Travis Perkins hire out the tool at £21/week. The recommended
Celotex has a multilayer surface to provide a more reliable fixing. My
supplier could not promise a reasonable delivery as PIR insulation
deliveries from Celotex have suddenly become unreliable. I'll probably
go with clip rails at 1m and shove in some intermediate clips and at the
bends.

Question for the chemists... what is the surface coating on the
aluminium foil? Cleans off readily with acetone and accepts the supplied
tape readily but *duct tape* needs it cleaned off first.

Floor heating suppliers provide a thin foam perimeter sheet to provide
expansion space for the screed but Celotex show an upstand of PIR foam
to insulate perimeter walls. Do I use both?

How resilient is the foam they suggest?

Not very! Light finger tip pressure would flatten it.

(there is some, but not much give in PIR foam when the load is
distributed over a wide area)

OK. Double up for the perimeter walls and foam only for the partitions.
My longest run is 8m which is the threshold for expansion joints
although I could hide one at a doorway.



--
Tim Lamb

Tim Lamb wrote:

John Rumm wrote:

Have you looked at the staple fixing options? You can get a long arm
device that sticks staples into the floor (without needing to bend etc)
to hold the pipes in place.

Yes. Travis Perkins hire out the tool at £21/week.

RRP £343.79 !!

On 30/07/17 21:27, Tim Lamb wrote:
In message , John
Rumm writes
On 30/07/2017 10:17, Tim Lamb wrote:
Installing the underfloor heating has neared the top of the jobs list.

Despite much reading of suppliers PDFs and head scratching there are
still areas of uncertainty:-)

Current thinking for the screeded area is to use self adhesive clip
rails over the Celotex foam. Spacing between rows seem to vary from
750mm to 2.0m depending on source.

Have you looked at the staple fixing options? You can get a long arm
device that sticks staples into the floor (without needing to bend
etc) to hold the pipes in place.

Yes. Travis Perkins hire out the tool at £21/week. The recommended
Celotex has a multilayer surface to provide a more reliable fixing. My
supplier could not promise a reasonable delivery as PIR insulation
deliveries from Celotex have suddenly become unreliable. I'll probably
go with clip rails at 1m and shove in some intermediate clips and at the
bends.

Question for the chemists... what is the surface coating on the
aluminium foil? Cleans off readily with acetone and accepts the supplied
tape readily but *duct tape* needs it cleaned off first.

Floor heating suppliers provide a thin foam perimeter sheet to provide
expansion space for the screed but Celotex show an upstand of PIR foam
to insulate perimeter walls. Do I use both?

How resilient is the foam they suggest?

Not very! Light finger tip pressure would flatten it.

(there is some, but not much give in PIR foam when the load is
distributed over a wide area)

OK. Double up for the perimeter walls and foam only for the partitions.
My longest run is 8m which is the threshold for expansion joints
although I could hide one at a doorway.



Why are ytou using celotxe fore floor insulation? Unless its first
floor, everyone else uses polystyrene...


Dont knock yourself out about how to locate the pipes. Anything that
will stand presurising and then screeding or concrete floating will do.
Meat skewers and tie wraps os probably good enough.

On the new builds here they simply pushed plastic staples in by hand.


Edge expansion is unimporatnt, as long as there is one.


--
€œIt is hard to imagine a more stupid decision or more dangerous way of
making decisions than by putting those decisions in the hands of people
who pay no price for being wrong.€�

Thomas Sowell

In message , The Natural Philosopher
writes
On 30/07/17 21:27, Tim Lamb wrote:
In message , John
Rumm writes
On 30/07/2017 10:17, Tim Lamb wrote:
Installing the underfloor heating has neared the top of the jobs list.

Despite much reading of suppliers PDFs and head scratching there are
still areas of uncertainty:-)

Current thinking for the screeded area is to use self adhesive clip
rails over the Celotex foam. Spacing between rows seem to vary from
750mm to 2.0m depending on source.

Have you looked at the staple fixing options? You can get a long arm
device that sticks staples into the floor (without needing to bend
etc) to hold the pipes in place.
Yes. Travis Perkins hire out the tool at £21/week. The recommended
Celotex has a multilayer surface to provide a more reliable fixing. My
supplier could not promise a reasonable delivery as PIR insulation
deliveries from Celotex have suddenly become unreliable. I'll probably
go with clip rails at 1m and shove in some intermediate clips and at
the bends.

Question for the chemists... what is the surface coating on the
aluminium foil? Cleans off readily with acetone and accepts the supplied
tape readily but *duct tape* needs it cleaned off first.

Floor heating suppliers provide a thin foam perimeter sheet to provide
expansion space for the screed but Celotex show an upstand of PIR foam
to insulate perimeter walls. Do I use both?

How resilient is the foam they suggest?
Not very! Light finger tip pressure would flatten it.

(there is some, but not much give in PIR foam when the load is
distributed over a wide area)
OK. Double up for the perimeter walls and foam only for the
partitions. My longest run is 8m which is the threshold for expansion
joints although I could hide one at a doorway.



Why are ytou using celotxe fore floor insulation? Unless its first
floor, everyone else uses polystyrene...
Good question. Specified by architect in building reg. plans. Should
have been GA3000Z but hard to get locally.


Dont knock yourself out about how to locate the pipes. Anything that
will stand presurising and then screeding or concrete floating will do.
Meat skewers and tie wraps os probably good enough.
:-)

On the new builds here they simply pushed plastic staples in by hand.
OK


Edge expansion is unimporatnt, as long as there is one.
Right.

I was curious about the glue issue when I found duct tape would not
reliably attach to offcuts I was assembling for machine cutting.



--
Tim Lamb