DIY ensuite bathroom replacement - build log

[Participant]

Not like you to spot any dimensional non conformoties with a niche though?


Now you raise it it makes sense. You could just pack a few boards back over to raise the existing one? I actually have some odd off cuts in Stratford I'm getting rid of if required.

Very kind of you, I'm not in the UK for a couple of weeks but if you still have them when I get back, I might take them off your hands.

Probably too late, but for the light above the shower head, presuming your other opening to the right in the photo is your extraction point, I'd combine the two and get a lit extraction cover:

Along the lines of this, but you get a wide range, depending on the aesthetic (some are more closed in/vent looking) and airflow you want..

It's perfect for us, really looks neat and combines the two in one, plus ones with standard bulbs allows you to get the colour temp/brightness you want..

I didn't realise you could get those, I thought they all came as part of a ceiling extractor fan. Will look into that thanks. Think someone previously suggested something similar above and it went over my head, if they meant the same thing.

 

[Participant]

also, are you tiling across the top of the boxed section into the window ledge (I have that) - are those levels good so you don't impinge on window after any backing boards are layed.

Good shout, yes I'm tiling that and the levels are good and there's plenty of room. Will double check that though.

 

[Participant]

Below is a picture of my waste arrangement as it leaves the bathroom into the garage below.

I've come across some knowledge on the internet that has made me think I've not done this correctly, specifically with respect to the 90 degree street elbows you can see.

On the bottom left is the 32mm basin waste...I think this will be ok as it's horizontal into vertical?

But on the right and above are two 40mm 90 degree street elbows for the shower waste. Will I get problems with the flow or future blocking susceptibility with this arrangement?

I've got ply down but nothing else yet, so could cut some away and reconfigure, but it would probably take me several hours so would rather avoid unless it's necessary. I've tested everything of course and flow is perfect (at the moment without soap and hair buildup!).

That said I'd rather do it right than worry down the line, so should I replace the street elbows with swept elbows just to be safe?

I could access the whole thing through the garage ceiling below, so could theoretically carry on as is then fix from below if I ever had flow issues. What would you do?

 

[Participant]

Not sure there is a better answer other than maybe removing the 90 in favour of a gentler fall. For a shower, I imagine it'll be fine?

That's what I should do guess. Just from observing the flow when I chucked a bucket of water down it, it seems like a waste of time and I also think it's fine for a shower with a 40mm pipe and a good fall.

Imagine it's more of an issue for soil pipes with solids slowing down at the sharp bend?

how far do the waste pipes run before intercepting a vented soil stack pipe, (recently realised had one in the new loft I'm planning boarding)
versus your bath say, to maximise flow/evacuation
could still do some drain deblocking even with existing right angles though.

The pipe runs 2.5m before connecting with the main soil stack, but the fall is spot on (and I could even improve it further only working in the garage).

I also think I could snake it ok even with the 90s. We have a good drain snake that is very flexible.

It will just be hard to sweep in future if you ever needed to. If it's a good mcalpine trap should be fine.

If it's easy access thru a garage below I'd just leave as is and multi tool ceiling in future if you ever unlikely had issues.

This is what I'm tempted to do, only issue is if I'm honest it's because of laziness and not wanting to compromise a very solid sub floor. Lesson learned for the other bathroom at least and there's no access from below with that one, so I'd rather make this mistake with this ensuite.

Why is the waste exiting the trap to the right and not to the left? Shorter pipework if you go left and through the joist?

I decided, rightly or wrongly, that I didn't want to compromise the joist further as it already has some dubious notches, and that the lesser of two evils was to take the pipe to the right then under the joist.

 

[Participant]

Ah, so that pipe goes under rather than through

Yes, doesn't interfere with joist at all.

 

[Participant]

Can you not look at a bottom exit trap? McAlpine do make them, and it would remove an element of the pipework without compromising the joists. Could then go straight down, use a swept 90 degree bend and connect to the pipework.

90mm Vertical Shower Trap | McAlpine Plumbing

Achieve efficient vertical shower drainage with the 90mm Vertical Shower Trap, ensuring reliable water flow in your plumbing system.

mcalpineplumbing.com

That's bloody good, had no idea that existed. However with the ply sub floor now down and all the info I've got above and from the internet, I'm wondering if it will make any tangible difference.

I've decided to proceed as it is and rectify from below if there are ever any significant issues.

I strongly suspect that it'll never be a problem and that the sharp elbow guide pertains mainly to poo and TP.

 

[Participant]

Finally did some more on this today...I have so many commitments impairing progress! Don't they realise I'm trying to bathroom?

Also the combi boiler stopped producing hot water today, yay. Suspiciously it was just after I finished flushing the pipes in this bathroom...

Today's progress was:

- Remove more ply around the shower waste hole with a multi tool, to make sure there's enough play to lift it up onto the underside of the shower tray once there's a 10mm bed of tile adhesive.

- Put some more wood between studs to screw accessories into.

- Finished reframing the new niche dimensions.

- Got some boards up.

-

 

[Participant]

Had an interesting one this morning - no (or only luke warm) hot water coming through the taps from the combi. Heating was fine.

After a bit of troubleshooting, I realised that I'd not put the rubber stops back into the Grohe rough-in box which was allowing hot to mix in the box when house taps were opened. I'd have thought the isolating valve (full bore) would have prevented that but I guess not.

All sorted now, but I thought our boiler had lunched itself and that it was my fault (which it was I guess). Wife was giving me grief.

 

[Participant]

Two walls boarded then I ran out of washers, which Mr. Amazon is delivering two more boxes of tomorrow.

Finally getting somewhere.

Tomorrow I'm going to prime the brick wall and floor and hopefully either finishing the wall boarding, or finally fit the shower tray (which I'm ******** myself about).

 

[Participant]

Use a classiseal if you haven't already fitted it.

I've got an "Abacus No More Leaks" sitting in the garage. I had a discussion with someone earlier in this thread about this vs. classiseal. Do you reckon the Abacus one is OK? It looks like it sits on top of the shower tray where the classiseal goes behind it, which I can't see why that's better.

 

[Participant]

Finally installed the shower tray and finished (nearly) the wall boarding today.

Didn't really enjoy the shower tray part - I was worried about level / shower water running to waste, build up height of tray vs. tiled floor (tray high enough to be level or above finished floor), consistency of tile adhesive, alignment of waste, made a right mess of the sides, etc. All was well in the end though. I used S2 tile adhesive at a depth of about 15mm in the end.

Tomorrow is boarding the final bits of the wall around the window (with scraps, as I've nearly run out of boards) and hopefully getting the floor down with some SLC.

 

[Participant]

Finally fully boarded. Floor is glued and screwed with S2 and about £100 of Wedi washers!

Next is some waterproof sealant (Mega Strength STS) between the rest of the boards, ufh mat and self-levelling compound, and it's ready to tile.

I have £1k of tiles and a Montolit Masterpiuma 63P5 in the garage ready to go.

 

[Participant]

Fully sealed and tanked and finally ready for tiling

I love the STS Mega Strength adhesive, which is 100% (sea)water proof and has been used between every board joint that can feasibly get wet. Between this, the acrylic primer, the tanking and the XPS boards (as well as the tiles / grout and SLC), if it leaks then I give up!

 

[Participant]

Did you tape the joints as well?

I did on the shower wall area, but this (as well as the tanking membrane) was unnecessary as per the manufacturer's instructions, because this product replaces tape being 100% waterproof and foaming slightly to fill gaps.

 

[Participant]

Below is a picture of my waste arrangement as it leaves the bathroom into the garage below.

I've come across some knowledge on the internet that has made me think I've not done this correctly, specifically with respect to the 90 degree street elbows you can see.

On the bottom left is the 32mm basin waste...I think this will be ok as it's horizontal into vertical?

But on the right and above are two 40mm 90 degree street elbows for the shower waste. Will I get problems with the flow or future blocking susceptibility with this arrangement?

I've got ply down but nothing else yet, so could cut some away and reconfigure, but it would probably take me several hours so would rather avoid unless it's necessary. I've tested everything of course and flow is perfect (at the moment without soap and hair buildup!).

That said I'd rather do it right than worry down the line, so should I replace the street elbows with swept elbows just to be safe?

I could access the whole thing through the garage ceiling below, so could theoretically carry on as is then fix from below if I ever had flow issues. What would you do?

Just to follow up on the above...

As I was fitting the shower tray, I realised that I'd forgotten to solvent weld one of the joints in the pipes shown above. I was waggling the pipes around and one of the joints just separated entirely .

Obviously I'm very glad that I found this before installing the tray and I took the opportunity to replace the street elbow with a swept 90 bend instead. Much better.

 

[Participant]

Today I primed the floor backer boards with Ultra Tilefix (Instarmac) Pro Primer, after a call with their technical support line, when they confirmed that I will need to:

- Prime the backer boards with neat primer as the boards are non porous
- Prime the ufh mat with neat primer again to ensure the tape doesn't cause any issues
- Prime the SLC with a 3:1 water: primer mix
- Prime the SLC again with a 1:1 water: primer mix

Beginning to see why pros never follow the full process...they'll simply never be able to compete on time and cost.

The next 'complication' anyway is that I've laid the ufh mat and completely ignored the rules on minimum distances between cables and between cable and wall. This is because my 4 sqm mat was somehow way too big for my 5.7 sqm (incl 1200 x 800 tray) bathroom.

I cbf to change it, so I'm gonna send it and keep the temperature at modest levels.

There are warnings everywhere about 50mm minimum gaps, but I can't find information about what will actually happen if the gap is less than this in some places. We're about to find out lol.

 

[Participant]

This week/end I've prepared the floor (primed), laid, relaid, and mucked around with UFH, and laid self-levelling compound. I used Ultra Tilefix's two-part SLC for this, which seems pretty good. Easy to mix and good flow, as you'd expect I guess so proof will be in lack of floor / floor tiles cracking!

Quite a few detailed photos below:

Using expanding foam to block any gaps to stop the SLC flowing where it's not meant to

Channels in the boards for the sensor conduit and cold tail joint to sit in

Power and sensor wires fished back up to the backbox

More holes filled with foam, and I used a hot glue gun to stick the cable down rather than tape, which worked much better and minimises potential issues with the tape adhering to the SLC

SLC laid, wet

SLC now OK for light foot traffic after a few hours

I have a slight problem with my tiles / tiling layout.

My plan was to line up the floor tile grout lines with the wall grout lines so there's a single line at each joint as they're both 600mm wide, or were meant to be. For some reason the floor tiles I've received are only 598mm wide, meaning I think I'm going to have an issue doing this.

I could either ditch the alignment entirely, use 3mm grout joints on the floor which I think should make the centre of the grout lines line up all the way along, just send it and hope it's not obvious, or 4thly attempt to moan to Tile Mountain - problem is they're exactly what we want otherwise. The gap would be most visible right in front when you enter the room, so I could line it up here and hope it's OK.

Edit: seems people think 2mm on a floor is a bit skinny anyway, so if I use 4mm spacers instead and 2mm on the wall I should only get 2mm deflection across the whole wall, i.e. for all intents and purposes invisible. Sound reasonable?

 

[Participant]

I used google sketchup when tiling my bathroom to work out the best layout for the tiles, means you can have a play around with it.

That sounds good I've never used that, however I know my layout, the issue is I did not know that tiles advertised as 600x600 would only be 598 x 598 .

 

[Participant]

I actually think if I centre the tiles in the centre of the wall, the biggest discrepancy will be only 5mm to either side of centre, which with colour-matched grout will probably be hard to notice in a finished room especially with the shower tray breaking things up on the left and the toilet and cabinet on the right.

I'm really keen on 2mm grout lines where possible.

 

[Participant]

SLC primed (twice) per Instarmac's technical support and setting out has started.

I'm going to (unusually) tile the whole floor first and protect it when doing the walls, because I want to line up the grout joints and this is the only real to do that in a room that isn't perfectly square.

I think everything should line up OK with nice big cuts top and bottom; the niche height vs. the flush plate / shelf might be an issue, but I don't think I'll be forced into any really small cuts if I'm careful.

Speaking of cutting, lots of grinder batteries are charged and a sexy brand new Montolit Masterpiuma 63P5 is ready to go. Better be better than the last junk tile cutter I got from Screwfix, which fractured everything and went straight back.