Eat yer heart out @onoff: I can't put this off any longer

[ProDave]

we have a squegee on a long pole so we can dry the floor without bending.

[ProDave]

2 minutes ago, Nickfromwales said:

 

If you’ve tanked and sealed properly you don’t have to panic about that detail.  

It is preferable but not life or death. I’ve done enough “grief free” wetrooms to know ?

A true Wetroom install should be OK to use WITHOUT EVER TILING IT, remember that and you’ll be fine. ?

 As @Jeremy Harris pointed out, if you do walls first with multipanel, and then tile the floor you risk the detail of water running down the wall and sitting in a channel and soaking into the wooden backing of the multipanel unless you seal it absolutely perfectly.

 

A LOT easier to floor first, fit the multipanel onto the floor with a very small gap sealed with CT1 etc.

[Nickfromwales]

1 minute ago, ProDave said:

 As @Jeremy Harris pointed out, if you do walls first with multipanel, and then tile the floor you risk the detail of water running down the wall and sitting in a channel and soaking into the wooden backing of the multipanel unless you seal it absolutely perfectly.

 

A LOT easier to floor first, fit the multipanel onto the floor with a very small gap sealed with CT1 etc.

Maybe. 
But.....

I wouldn’t fit multi panel as it’s a ticking time bomb. 
I did a whole house ( all bathrooms ) for an Ebuild member and indeed tiled the floors / fitted shower trays first, then scribed the Mermaid panels with a router, and dropped the bottoms of the panels into a 1/2” bead of clear CT1. The excess that displaced after pushing the panels down and home was removed by wet wipes and CT1 Multi Solve spray and I’ll bet my left testicle that they’ll be watertight until I snuff it. 
Jobs as good as you make it ?

[Jeremy Harris]

16 minutes ago, Nickfromwales said:

Maybe. 
But.....

I wouldn’t fit multi panel as it’s a ticking time bomb. 
I did a whole house ( all bathrooms ) for an Ebuild member and indeed tiled the floors / fitted shower trays first, then scribed the Mermaid panels with a router, and dropped the bottoms of the panels into a 1/2” bead of clear CT1. The excess that displaced after pushing the panels down and home was removed by wet wipes and CT1 Multi Solve spray and I’ll bet my left testicle that they’ll be watertight until I snuff it. 
Jobs as good as you make it ?

 

 

All I can say is that in our last house I fitted Multipanel to the whole bathroom, including around the shower.  That was around 2006/7.  Ten years later I was so impressed with the way it had performed, that I did both bathrooms in the new house with the stuff.

 

The only thing to avoid with it is to seal the base as described, with a ~3mm thick bead of sealant under the lower edge, and to never use the plastic seal moulding that Multipanel recommend.  That stuff is a design disaster, and should be avoided.

 

There was a cheap and nasty laminate board around for a while, that used an MDF core.  I can't recall what it was called, but it was far from being a good design.  At least the birch ply in the Multipanel stuff is a heck of a lot more robust, and with a layer of decent laminate either side it's a pretty damned good product.

[Construction Channel]

Fwiw the Tiler I used. (and have known and trusted for a long time) did the floor first. Also +1 to plenty of tanking. luckily we had a bunch of the liquid left over from work but I had to buy the tape from here. 

Lots cheaper than finding a leak 

 

Sealing tape D11, 10-50 Lfm,... https://www.amazon.co.uk/dp/B079NGGLBW?ref=ppx_pop_mob_ap_share

 

 

[ToughButterCup]

The drain: I want it to be rodable.

 

How much lower than the bottom of the drain assembly do I need to go? 

 

[ToughButterCup]

1 hour ago, Nickfromwales said:

...I’ll bet my left testicle that they’ll be watertight until ...

 

The other is in the Albert Hall is it?

[puntloos]

3 hours ago, Onoff said:

 

I notice that everytime I have a sh!t.

 

[Construction Channel]

2 hours ago, AnonymousBosch said:

The drain: I want it to be rodable.

 

How much lower than the bottom of the drain assembly do I need to go? 

 

How far have you got available? 

[ToughButterCup]

Its 100mm, Ed

 

Exactly as planned - in our case a bit of a suprise really ?

 

So the drain from the shower tray - as shown above will likely cut into the top bit of the top layer of the the EPS 100 . 

The Radon DPM layer is 200 below the bottom of the concrete

 

Does that matter?

There is a Wedi  Riofino  shower tray that has a horizontal drain: but I suspect there might be a hissing and a booing about horizontal drains from the Commentariat about that {?}

It shows that the drain is 60mm or so deep ( i.e. dig out 65mm), which means that I would not have to cut into the EPS 100 below it.

 

What do you think?

[PeterW]

43 minutes ago, AnonymousBosch said:

There is a Wedi  Riofino  shower tray that has a horizontal drain: but I suspect there might be a hissing and a booing about horizontal drains from the Commentariat about that {?}

 

 

 

It only has a 40mm drain... 50mm when buried under the floor is preferable. How far does it have to run..??

[joe90]

9 minutes ago, PeterW said:

50mm when buried under the floor is preferable.

yes, the welsh wizard told me to go min 50mm drain runs.

[ToughButterCup]

23 minutes ago, PeterW said:

[...]

How far does it have to run..??

 

2 meters ...

[PeterW]

Ok so definitely 50mm

[Onoff]

56 minutes ago, joe90 said:

yes, the welsh wizard told me to go min 50mm drain runs.

 

Me too. Works a treat. And don't forget to fit an anti siphon trap to the basin if it shares the same waste pipe so no gurgling. Again from the WW.

[joe90]

I ran all my pipes individually to main 110 pipe, I don’t like sharing drain runs as they can lead to “gurgling,”

[Onoff]

6 minutes ago, joe90 said:

I ran all my pipes individually to main 110 pipe, I don’t like sharing drain runs as they can lead to “gurgling,”

 

I don't like going to 110mm pipes here! "Back up" issues! ?

[Temp]

18 hours ago, AnonymousBosch said:

The drain: I want it to be rodable.

 

I'm about to fit a MacAlpine ST90CB10-70 top access trap that appears to be rod-able through the removable top access trap.  

 

If that's not sufficient one option is to have a small access panel in the floor to one side of the shower tray.  Under that you have a gentle 90 or 45 bend with a cap on that leads into the shower waste pipe.

[Temp]

Here is the McAlpine ST90CB10-70 top access trap with trap removed. Note that if your tray is very thin more of the outlet is obscured as the top part screws in further. However in that case you could cut off few turns of the threaded part to get better access. 

 

[Construction Channel]

4 hours ago, AnonymousBosch said:

What do you think?

? I know about as much as you about this stuff but I was trying to ask the inevitable questions. 

 

Next questions. 

What is your planned floor finish? (tiles, vinyl etc) will effect tile in traps... 

 

Do you have a link to the trap you had planned to use? 

Someone will want to look over the technical specs for you. 

 

Would the "tray" you mentioned be wheelchair accessible? 

 

Do you already have a boss fitted to the stack dictating a height/fall or will you install that after? 

 

 

[ToughButterCup]

16 hours ago, Construction Channel said:

[...]

What is your planned floor finish? (tiles, vinyl etc) will effect tile in traps... 

Do you have a link to the trap you had planned to use? 

[...]

Would the "tray" you mentioned be wheelchair accessible? 

Do you already have a boss fitted to the stack dictating a height/fall or will you install that after? 

 

Floor finish will be tiles

The trap I want to use is this one , or at least something like it : a circular drain hole set in the middle of a  sloped surface ready for tiling.

 

 

 

Wheelchair accessibility is a given.

Its so tempting to forget it and simply shove in a shower tray and be done with it -  a few people have suggested I do so.

They probably haven't  got an injured back, or arthritic hips. Those  little jokers are not going to go away.

 

A boss on the stack? 

No. A straight piece of 110 pipe sticks up 100mm above FFL

[ToughButterCup]

18 hours ago, Temp said:

Here is the McAlpine ST90CB10-70 top access trap with trap removed. Note that if your tray is very thin more of the outlet is obscured as the top part screws in further. However in that case you could cut off few turns of the threaded part to get better access. 

 

Thanks very much @Temp

18 hours ago, Temp said:

[...]

a small access panel in the floor to one side of the shower tray.  Under that you have a gentle 90 or 45 bend with a cap on that leads into the shower waste pipe.

 

Good idea. Just like I have seen done on an outside drain, where the pipe is really inaccessible, but a 45 degree bend incorporated into the pipe makes the whole length (bar a few mm) cleanable.

 

[Cpd]

On 07/01/2020 at 19:58, Jeremy Harris said:

All I can say is that in our last house I fitted Multipanel to the whole bathroom, including around the shower.  That was around 2006/7.  Ten years later I was so impressed with the way it had performed, that I did both bathrooms in the new house with the stuff.

 

The only thing to avoid with it is to seal the base as described, with a ~3mm thick bead of sealant under the lower edge, and to never use the plastic seal moulding that Multipanel recommend.  That stuff is a design disaster, and should be avoided.

 

I used the metal bottom channel and filled it with CT1 and pushed the panel into it, cleared it as @Nickfromwales described and it’s been totally fine for the last 3+ years. My set up was a bit different as I was using a shower tray with inbuilt up-stands and the board came over these up-stands but not all the way down so I wanted a clean finish on the bottom of the board  without any exposed silicone.  I would use the system again as I love lot having ANY silicone within the shower area but I should have put the boards a bit higher up as I only left a small gap below them and the shower tray which is hard to clean. 

[nod]

On 07/01/2020 at 19:32, Nickfromwales said:

Not on my shift mate ?. 
Always floor first and then tile up and away. The only time I break that rule is if it’s mosaic in a specific area and I’ll then size the opening to take full sheets of mosaic. 

 

If you’ve tanked and sealed properly you don’t have to panic about that detail.  

It is preferable but not life or death. I’ve done enough “grief free” wetrooms to know ?

A true Wetroom install should be OK to use WITHOUT EVER TILING IT, remember that and you’ll be fine. ?

I agree it should be watertight before any tiles go down 

The same as a roof 

Ive been tiling for forty years 

and tilers working for me for thirty 

If a tiler in my employ tiled a floor first I would sack him on the spot 

Apart from anything else you are walking on what you have just laid 

 

[Nickfromwales]

1 hour ago, nod said:

I agree it should be watertight before any tiles go down 

The same as a roof 

Ive been tiling for forty years 

and tilers working for me for thirty 

If a tiler in my employ tiled a floor first I would sack him on the spot 

Apart from anything else you are walking on what you have just laid 

 

25 years for me so you get grandfather rights over me lol ?. 
When you stand in a bathroom and look directly down the wall to the floor, on one of my tiling jobs, all you see is tile.
 

The grout line that’s left when you tile the floor afterwards, and I have had to do it that way a few times, isn’t acceptable to my OCD, plus under grouting ( under the last cut wall tile ) vs grouting the gap between the cut floor tile and the existing bottom wall tile isn’t cricket. If you silicone over that on one of my jobs.....you’d be sacked on the spot too ??. 
My bathrooms are as near to ‘silicone free’ as I can get them. Hate the stuff. 
A lot of the tiles these days can be bought to compliment wall - floor junctions. So if the grout lines are to go down one wall / through the floor / back up the opposite wall, on both the parallel and perpendicular grout lines then tiling the floor first is absolutely the only option. 
 

Antinox or 4mm plywood will give ample floor protection.