Having failed to pay proper attention during earlier discussions I
wonder if someone can kindly highlight the conclusions?

Early next week I hope to be laying polypipe under floor heating and
will shortly thereafter be badgered by my builder for a decision on
flooring so he can lay screed.

I doubt there is sufficient space to use battens or plywood and yet
match existing floor levels so gluing direct seems the obvious route.
This also reduces the *insulation* effect of the flooring.

Flooring seems to come in a huge range of thickness and a variety of
substrate materials to say nothing of the fixing options! Entrance, hall
and shower room are likely to be in 300 x 300mm ceramic tiles which,
having measured some existing, are about 13mm thick: including fixing.

I suppose minor variations can be taken care of at thresholds but is
sub-15mm engineered wood going to do the job?

What happens to expansion/contraction with glued fixing?

Can you still get that very thin door matting to drop in a 13mm deep
well?

regards
--
Tim Lamb

Tim Lamb wrote:
Having failed to pay proper attention during earlier discussions I
wonder if someone can kindly highlight the conclusions?

Early next week I hope to be laying polypipe under floor heating and
will shortly thereafter be badgered by my builder for a decision on
flooring so he can lay screed.

I doubt there is sufficient space to use battens or plywood and yet
match existing floor levels so gluing direct seems the obvious route.
This also reduces the *insulation* effect of the flooring.

Flooring seems to come in a huge range of thickness and a variety of
substrate materials to say nothing of the fixing options! Entrance, hall
and shower room are likely to be in 300 x 300mm ceramic tiles which,
having measured some existing, are about 13mm thick: including fixing.

I suppose minor variations can be taken care of at thresholds but is
sub-15mm engineered wood going to do the job?


Yes, but do NOT glue it. Lay floating.

What happens to expansion/contraction with glued fixing?

It bubbles up/cracks the glue.

Can you still get that very thin door matting to drop in a 13mm deep well?

Not particularly, no. Do a deeper well in the screed.

regards

Tim Lamb wrote:

Can you still get that very thin door matting to drop in a 13mm deep well?

yes, plenty available, including solid rubber, rubber matrix, carpet
tile, jute-like mats, etc. The lighter types of mat can tend to curl
slightly if thin, and ideally will want gluing down. Solid rubber
behaves very well, if you're not looking for a scraping action.


NT

In message
, NT
writes
Tim Lamb wrote:

Can you still get that very thin door matting to drop in a 13mm deep well?

yes, plenty available, including solid rubber, rubber matrix, carpet
tile, jute-like mats, etc. The lighter types of mat can tend to curl
slightly if thin, and ideally will want gluing down. Solid rubber
behaves very well, if you're not looking for a scraping action.

Good.

We have the Jute-like mat. Still OK after 15 years of muddy wellies:-)

regards

--
Tim Lamb

In message , The Natural Philosopher
writes
Tim Lamb wrote:
Having failed to pay proper attention during earlier discussions I
wonder if someone can kindly highlight the conclusions?
Early next week I hope to be laying polypipe under floor heating and
will shortly thereafter be badgered by my builder for a decision on
flooring so he can lay screed.
I doubt there is sufficient space to use battens or plywood and yet
match existing floor levels so gluing direct seems the obvious route.
This also reduces the *insulation* effect of the flooring.
Flooring seems to come in a huge range of thickness and a variety of
substrate materials to say nothing of the fixing options! Entrance,
hall and shower room are likely to be in 300 x 300mm ceramic tiles
which, having measured some existing, are about 13mm thick: including

I suppose minor variations can be taken care of at thresholds but is
sub-15mm engineered wood going to do the job?


Yes, but do NOT glue it. Lay floating.

Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

What happens to expansion/contraction with glued fixing?

It bubbles up/cracks the glue.

Oh! Right.

regards
--
Tim Lamb

Tim Lamb wrote:
In message , The Natural Philosopher
writes
Tim Lamb wrote:
Having failed to pay proper attention during earlier discussions I
wonder if someone can kindly highlight the conclusions?
Early next week I hope to be laying polypipe under floor heating and
will shortly thereafter be badgered by my builder for a decision on
flooring so he can lay screed.
I doubt there is sufficient space to use battens or plywood and yet
match existing floor levels so gluing direct seems the obvious route.
This also reduces the *insulation* effect of the flooring.
Flooring seems to come in a huge range of thickness and a variety of
substrate materials to say nothing of the fixing options! Entrance,
hall and shower room are likely to be in 300 x 300mm ceramic tiles
which, having measured some existing, are about 13mm thick: including
I suppose minor variations can be taken care of at thresholds but is
sub-15mm engineered wood going to do the job?


Yes, but do NOT glue it. Lay floating.

Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?
You will curse without it. Clack,clack, clack...:-)

What happens to expansion/contraction with glued fixing?

It bubbles up/cracks the glue.

Oh! Right.

regards

Tim Lamb wibbled:


Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

I used Tredair Boardwalk - seems successful. It's a 4mm dense underlay with
acoustic reduction properties and an integral vapour barrier (foil top).

Cheers

Tim

In message , Tim S
writes
Tim Lamb wibbled:


Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

I used Tredair Boardwalk - seems successful. It's a 4mm dense underlay with
acoustic reduction properties and an integral vapour barrier (foil top).

OK. Noted.

So 15mm for Kahrs mid range plus 4mm underlay.... I'll ask the builders
to allow for 20mm flooring in the main area. On line ceramic tile
suppliers are rather coy about publishing tile thickness but the
existing total 13mm so I may attempt a different screed height for the
entrance and shower room.

regards

--
Tim Lamb

Tim Lamb wrote:
In message , Tim S
writes
Tim Lamb wibbled:


Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

I used Tredair Boardwalk - seems successful. It's a 4mm dense underlay
with
acoustic reduction properties and an integral vapour barrier (foil top).

OK. Noted.

So 15mm for Kahrs mid range plus 4mm underlay.... I'll ask the builders
to allow for 20mm flooring in the main area. On line ceramic tile
suppliers are rather coy about publishing tile thickness but the
existing total 13mm so I may attempt a different screed height for the
entrance and shower room.


4-6mm decent floor tiles. Add 3mm for cement over screed, and more like
6mm over wood. Its easy enough to spend more on tile cement and make the
bed thicker ..in my case up to 20mm to allow for crap screeding.


regards

In message , The Natural Philosopher
writes
Tim Lamb wrote:
In message , Tim S
writes
Tim Lamb wibbled:


Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

I used Tredair Boardwalk - seems successful. It's a 4mm dense
underlay with
acoustic reduction properties and an integral vapour barrier (foil top).
OK. Noted.
So 15mm for Kahrs mid range plus 4mm underlay.... I'll ask the
builders to allow for 20mm flooring in the main area. On line ceramic
tile suppliers are rather coy about publishing tile thickness but the
existing total 13mm so I may attempt a different screed height for the
entrance and shower room.


4-6mm decent floor tiles. Add 3mm for cement over screed, and more like
6mm over wood. Its easy enough to spend more on tile cement and make
the bed thicker ..in my case up to 20mm to allow for crap screeding.

er... ours are 300 x 300mm square and around 10mm thick.

regards

--
Tim Lamb

Tim Lamb wibbled:

In message , Tim S
writes
Tim Lamb wibbled:


Hmm... so it has to be a *click* version? What about the membrane they
seem to insist on?

I used Tredair Boardwalk - seems successful. It's a 4mm dense underlay
with acoustic reduction properties and an integral vapour barrier (foil
top).

OK. Noted.

So 15mm for Kahrs mid range plus 4mm underlay.... I'll ask the builders
to allow for 20mm flooring in the main area. On line ceramic tile
suppliers are rather coy about publishing tile thickness but the
existing total 13mm so I may attempt a different screed height for the
entrance and shower room.

regards


Sounds about right - I came up 35mm ish - but I also has 12.5mm mamrox and
3-4mm tile adhesive.


Cheers

Tim