Pics:

https://drive.google.com/drive/folde...Hc?usp=sharing

or short https://goo.gl/32e4PL


Tiler did a great job tiling (I diy'd the screed and concrete slab) and
I have tested the fall with water and it runs into the drain nicely.


I woke up this morning with one huge panic though:

I wish I had insisted on tanking membrane.

I took advice from the tiler (who's old school) and he said not to
worry. Asked a builder mate and he did see it was necessary as it's
ground floor, on it's own concrete/celotex/screed self contained in its
own DPM wrapper isolated from the rest of the house.

I see that and that coloured my thinking - after all, the worse that can
happen is the screed gets wet and maybe waterlogs the celotex and rots
its foil face off over years (that can happen apparently). In one
respect the problem will at least be isolated and not affect the house.


The stupid thing is that I said I was worried about the edges to wall as
there may be movement there, so tiler added tanking edging strip - and
seeing how easy that was, I wish I'd said: stop, get some sheet membrane
and complete the seal.


But I was working at home, and juggling a dozen things and didn't have
time to think it through. Conversely I was also worried that membrane
might fail mechanically at some point.


I cannot see anything in the Building Regs approved docs that mentions
wetrooms let alone specifying membrane. Although I found a vague mention
of a British Standard somewhere. I've keyword searched Part A structure,
C Site preparation and resistance to contaminates and moisture, G
Sanitation, hot water safety and water efficiency and H Drainage and
waste disposal.

Strange - would have thought there'd be a mention...


So, kicking myself here... Might ring the BCO (new one, #3) and double
check - he's going to see this for the drains, and therefore might
ask... Pain to redo this section, but less of a disaster than if the
thing is complete.


I don't see a huge risk myself, but like putting marmox on the walls, it
would have been a fairly small inexpensive not difficult extra step...

I'm surprised the tiler didn't say "just do it, we always do that"
unless they don't always do that?

===

That's what I hate about doing this project - all the technical stuff is
on my shoulders and I don't know any experts (apart from relevant people
here) so I don't have anyone to really confer with. Kinda assumed a
tiler would know what was necessary. Builder mate is more "relaxed" than
me too...

Sorry - bit of a depressed moan

Tim Watts wrote:

I don't know any experts (apart from relevant people here) so I don't
have anyone to really confer with. Kinda assumed a tiler would know
what was necessary.
On a similar note, how worthwhile are the 'uncoupling' membranes (e.g.
DITRA) that I see on youtube? Have some bathroom floor tiling coming up
over floorboards, so was planning on cement board first, is isolation an
issue above that? Need to know my finished floor level before I can do
other work, so can't change mind later ...

On 16/09/17 11:32, Andy Burns wrote:
Tim Watts wrote:

I don't know any experts (apart from relevant people here) so I don't
have anyone to really confer with. Kinda assumed a tiler would know
what was necessary.


On a similar note, how worthwhile are the 'uncoupling' membranes (e.g.
DITRA) that I see on youtube? Have some bathroom floor tiling coming up
over floorboards, so was planning on cement board first, is isolation an
issue above that? Need to know my finished floor level before I can do
other work, so can't change mind later ...

Based on my state of mind, over screed, I'd say "use one because (in
retrospect) it's not hard". I thought these things were hard to use, but
it seems you just use tile adhesive to put them down (some others are
paint on, some use primers, this is the one Topps Tiles sell - it's a
"fabric" covered sheet about 1-2mm thick).

Based on me just noticing you said "floorboards" I would say it is
mandatory - even I would have done that.

Have a look at Marmox - I *believe* you can use their sheeting with some
additional edge seals and jointing tape to form a wetroom. They even
have floor panels with slope angles built in that will make life simpler.

On 16/09/17 11:42, Tim Watts wrote:

Have a look at Marmox - I *believe* you can use their sheeting with some
additional edge seals and jointing tape to form a wetroom. They even
have floor panels with slope angles built in that will make life simpler.

Oh and they have a great tech support line you can phone in Kent where
you can speak to a guy who knows his stuff... I rang them to check
weight loadings on the board if screwed to the wall.

Tim Watts wrote:

I thought these things were hard to use, but it seems you just use
tile adhesive to put them down (some others are paint on, some use
primers, this is the one Topps Tiles sell - it's a "fabric" covered
sheet about 1-2mm thick).
This one? At the price, no point in not using it for extra precaution
against cracking.

http://www.toppstiles.co.uk/tprod8778/durabase-ci-matting-1m2.html

Based on me just noticing you said "floorboards" I would say it is
mandatory - even I would have done that. Have a look at Marmox -
I *believe* you can use their sheeting with some additional edge seals
and jointing tape to form a wetroom.

I'm not aiming for wetroom, but anything that stops 'enthusiastic
splashing' ending up on the kitchen ceiling is a bonus.

They even have floor panels with slope angles built in that will make
life simpler.
Marmox, hardybacker, no-more-ply ... much to choose between them?

On 16/09/17 12:32, Andy Burns wrote:
Tim Watts wrote:

I thought these things were hard to use, but it seems you just use
tile adhesive to put them down (some others are paint on, some use
primers, this is the one Topps Tiles sell - it's a "fabric" covered
sheet about 1-2mm thick).
This one? At the price, no point in not using it for extra precaution
against cracking.

http://www.toppstiles.co.uk/tprod8778/durabase-ci-matting-1m2.html

That's why I'm kicking myself...

Bah...


I'm not aiming for wetroom, but anything that stops 'enthusiastic
splashing' ending up on the kitchen ceiling is a bonus.

Ah - not mandatory then. But wise to design.

They even have floor panels with slope angles built in that will make
life simpler.

Marmox, hardybacker, no-more-ply ... much to choose between them?

Marmox will be warmer to the touch and goes from 4mm to very thick. 4
or 6mm will do you.

It's lighter to handle too - Hardibacker boards weigh a ton.

I've had 20mm Marmox multiboard under my bathroom ceramic tiles for 8
years and it's been very good. I did leave it out from where the bath
feet and bog go and screed that level with SBR/3:1 cement after priming
the existing screed with SBR then cenement/SBR slurry.

That avoids risk of deformation under high load parts.

In message , Tim Watts
writes
Pics:

https://drive.google.com/drive/folde...Hc?usp=sharing

or short https://goo.gl/32e4PL


Tiler did a great job tiling (I diy'd the screed and concrete slab) and
I have tested the fall with water and it runs into the drain nicely.


I woke up this morning with one huge panic though:

I wish I had insisted on tanking membrane.

Hmm.. I plan to tank mine. 'kin expensive materials though!

I've opted for a wall side linear drain 900mm long. This came with a bit
of pre-trimmed tanking material. There seem to be two schools... always
tank over a boarded floor/might be a good thing with an in screed heat
source.

Ground floor, no heat, little worry:-)
--
Tim Lamb

On 16/09/17 14:42, Tim Lamb wrote:


There seem to be two schools... always
tank over a boarded floor/might be a good thing with an in screed heat
source.

That was the ambiguity I faced - it did not seem cut and dried...


Ground floor, no heat, little worry:-)

I sounded it out with the less technical people at home and drew a
decision diagram...

If we tile the walls and BCO asks "is it tanked", "no", "do it again" -
big disaster. He's going to inspect the room for the drains and
ventilation so he might well ask.


If we phone him and say "er, might have a problem, do you *require* it
to be tanked":

Yes) We redo the floor. 4 days of cost and 3m2 of tiles. Not a disaster
but annoying.

No) We run the risk and the worse that *could* happen is the celotex
gets waterlogged. That could take maybe 10 or more years (guess)

And we have some exposed screed in the under basin cupboard - it is
monitorable.

No risk of damage to house as DPM isolates the floor on all sides.


So I guess I should phone the BCO's office on Monday.

But I cannot find a single thing in the Approved Docs and I bet they
never used to tank these things in the 1960s? Or did they?

On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...

On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

PS Thanks

Tim Watts wrote:

On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...

I put the damp proofing under the electric heating and under a 10mm
insulating layer. It is the builder's choice of a paint-on 'membrane'
and I have no faith in it. But since with the heating and ventilation
the floor never stays wet more than half an hour I have no worries about
it at all. Even if the celotex, which is now about 150mm down did get
soaking wet I can't see any significant harm resulting. FWIW, our BCO
had no interest in the issue.

--

Roger Hayter

On 16/09/17 15:43, Roger Hayter wrote:
Tim Watts wrote:

On 16/09/17 14:42, Tim Lamb wrote:


Oh: yes there is heat, but wet, not electric. So no danger...

I put the damp proofing under the electric heating and under a 10mm
insulating layer. It is the builder's choice of a paint-on 'membrane'
and I have no faith in it. But since with the heating and ventilation
the floor never stays wet more than half an hour I have no worries about
it at all. Even if the celotex, which is now about 150mm down did get
soaking wet I can't see any significant harm resulting.

Thanks mate. As I was saying, when you have no one to talk too, ito's
easy to lose perspective... Good job I can come here

I never have this problem at work - I work in systems admin, where non
optimal solutions are easily undone or fixed - in fact it's how I get
stuff done - rough it for 80% of the benefit, then tart it up for the
final polish later.

But equally, we try to work to "best practises" too, and that's damn
hard in building when most people don't give a monkeys

The only thing I'm nervous about right now is spending £200k on new
server infrastructure - if I feck that up, I get to be reminded of it
every day for the next 5 years. Or not at all if I feck it up enough!

FWIW, our BCO
had no interest in the issue.

That's heartening - I will ring our office and see. Last bloke I spoke
to seemed quite helpful.

In message , Tim Watts
writes
On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...

er.. movement due to expansion? The floor heating advice is adamant
about expansion foam next to internal walls as well as 25mm PIR
insulation at the external ones.

I plan to use wallboard rather than tiles although I might run a row of
half tiles around the bottom and use silicon rather than grout for the
joint.


--
Tim Lamb

On 16/09/17 18:50, Tim Lamb wrote:
In message , Tim Watts
writes
On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...

er.. movement due to expansion? The floor heating advice is adamant
about expansion foam next to internal walls as well as 25mm PIR
insulation at the external ones.

I did add the foam around the edges. My calcs suggest the expansion of a
3m long floor from 10C to 40C would be about 1mm overall give or take.
All my edges will be sealed 3 times (sealed gap around tiles yesterday),
will seal Marmox to floor and tiles will have finishing sealant. And we
do have edging membrane on all edges under the tiles too - so that's a
4th layer.

That was the bit I thought of and I feel confident that will be fine.

The weakness in the scheme, if any, will be due to any porosity of the
surface I think...


I plan to use wallboard rather than tiles although I might run a row of
half tiles around the bottom and use silicon rather than grout for the
joint.



That's what I've done in every place - even the main bathroom which has
a cold floor.

In message , Tim Watts
writes
On 16/09/17 18:50, Tim Lamb wrote:
In message , Tim Watts
writes
On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...
er.. movement due to expansion? The floor heating advice is adamant
about expansion foam next to internal walls as well as 25mm PIR
insulation at the external ones.

I did add the foam around the edges. My calcs suggest the expansion of
a 3m long floor from 10C to 40C would be about 1mm overall give or
take. All my edges will be sealed 3 times (sealed gap around tiles
yesterday), will seal Marmox to floor and tiles will have finishing
sealant. And we do have edging membrane on all edges under the tiles
too - so that's a 4th layer.

The screeders blurb wants expansion joints if the run exceeds 8m.
Fortunately I have a convenient doorway so I can hide the expansion
strip under that.

That was the bit I thought of and I feel confident that will be fine.

The weakness in the scheme, if any, will be due to any porosity of the
surface I think...

I'm planning on ceramic tiles:-)
--
Tim Lamb

Tim Watts wrote:

On 16/09/17 18:50, Tim Lamb wrote:
In message , Tim Watts
writes
On 16/09/17 14:42, Tim Lamb wrote:

Ground floor, no heat, little worry:-)

Oh: yes there is heat, but wet, not electric. So no danger...

er.. movement due to expansion? The floor heating advice is adamant
about expansion foam next to internal walls as well as 25mm PIR
insulation at the external ones.

I did add the foam around the edges. My calcs suggest the expansion of a
3m long floor from 10C to 40C would be about 1mm overall give or take.
All my edges will be sealed 3 times (sealed gap around tiles yesterday),
will seal Marmox to floor and tiles will have finishing sealant. And we
do have edging membrane on all edges under the tiles too - so that's a
4th layer.

That was the bit I thought of and I feel confident that will be fine.

The weakness in the scheme, if any, will be due to any porosity of the
surface I think...


I plan to use wallboard rather than tiles although I might run a row of
half tiles around the bottom and use silicon rather than grout for the
joint.



That's what I've done in every place - even the main bathroom which has
a cold floor.

About 20mm stainless steel coving looks nice, is easy to seal and will
take up a little movement. Not entirely cheap. But the do
prefabricated 90deg, 135deg, 180deg, 270deg joining bits, which is good.

http://www.schluter.co.uk/dilex-hks-ehk-products.aspx

--

Roger Hayter

On 16/09/17 21:13, Roger Hayter wrote:

About 20mm stainless steel coving looks nice, is easy to seal and will
take up a little movement. Not entirely cheap. But the do
prefabricated 90deg, 135deg, 180deg, 270deg joining bits, which is good.

http://www.schluter.co.uk/dilex-hks-ehk-products.aspx



That is nice - I've never seen that before...

In message , Roger Hayter
writes

I plan to use wallboard rather than tiles although I might run a row of
half tiles around the bottom and use silicon rather than grout for the
joint.



That's what I've done in every place - even the main bathroom which has
a cold floor.

About 20mm stainless steel coving looks nice, is easy to seal and will
take up a little movement. Not entirely cheap. But the do
prefabricated 90deg, 135deg, 180deg, 270deg joining bits, which is good.

http://www.schluter.co.uk/dilex-hks-ehk-products.aspx

Interesting. Ta.

The seating looks wide enough for a range of tile thickness.

My efforts at running mastic sealant do not find approval from the
boss:-( Tooling and tiles don't go well either.


--
Tim Lamb

Tim Lamb wrote:

In message , Roger Hayter
writes

I plan to use wallboard rather than tiles although I might run a row of
half tiles around the bottom and use silicon rather than grout for the
joint.



That's what I've done in every place - even the main bathroom which has
a cold floor.

About 20mm stainless steel coving looks nice, is easy to seal and will
take up a little movement. Not entirely cheap. But the do
prefabricated 90deg, 135deg, 180deg, 270deg joining bits, which is good.

http://www.schluter.co.uk/dilex-hks-ehk-products.aspx

Interesting. Ta.

The seating looks wide enough for a range of tile thickness.

There's some flexibility by varying adhesive thickness, but they do
different tile thickness ones from about 6mm to 15mm.



My efforts at running mastic sealant do not find approval from the
boss:-( Tooling and tiles don't go well either.



--

Roger Hayter