Soil stacks, tiling, etc

[Pete Verdon]

Hi,

Some time in 2009 I'll probably get round to refitting the bathroom. I'll probably be bugging everyone for more advice when the time comes, but here's a couple of questions that spring to mind now.

Firstly, the soil stack. It actually rises through a corner of the bathroom, grey plastic pipe boxed in. Obviously the various drains, bog outlet, etc go into it now, but the new design will involve them coming from some different directions and possibly at different heights. If I were fitting these pipes to a new stack it would be fine, but I suspect that under the boxing it probably looks like swiss cheese. Is it possible to blank off old holes when making new ones? If the blanking kit takes up much room it's likely to get in the way of the new fittings. So, alternatively, is it possible to break and join the stack with a new section of pipe? The bathroom is the highest point at which anything drains into it, but I'm a little worried about moving the pipe up and down breaking the seal through the roof, which isn't easily accessible.

Secondly, tiling. I've not done much before (just replaced the odd cracked floor tile, which I found easy enough) but my natural assumption tends to be that whatever the job I'll do it myself. However, my Dad reckons that to get a good finish (and a ropey one would bug me no end) is beyond unskilled abilities, and I should get a professional in. He's just had his bathroom redone (at a price miles out of my league!) and it does look fantastic. Obviously this is a hard thing to judge, but would you say that good-quality tiling is beyond a careful but unskilled DIYer? If I did decide to get someone in just for that bit, any guess as to time and money (labour only) for wall & floor tiling of a 1.8m x 3.5m bathroom? I've never employed someone for something like this before so I don't even have a ballpark.

Cheers,

Pete

[Rod]

Regarding the stack pipe - all sorts of things are possible. Suggest you have a look here:

It is easy to connect a new piece of pipe - the only difficulty is cutting the existing pipe if it is awkwardly located in a corner.

There are rules about how multiple pipes are connected to a stack pipe. Can't remember the details but it's not complex - things like vertical distance between connections.

[Pete Verdon]

Cheers. I was sort of assuming that the current bog fitting (the one that matters) would be the strap-on type, but I guess it could just as well be something like the "Single Branch, 2 Boss Equal" from the link above. In that case I could probably just swivel it round 90º to point in the new direction. Or if it is a strap-on, cut out that section of pipe and replace with such a fitting. If I was doing that, though, I'd have to lift and lower the upper part of the pipe to slot it into the fitting, and as I said I'm worried about this breaking the seal where the stack passes through the roof. I don't know how that seal is made; access to the inside is tricky and I don't currently have a ladder that will reach the roof for the outside.

It is in a corner so it would be hard to get a hacksaw across it, but that just sounds like an excuse for a new tool :-) (some kind of dremel thing with a saw wheel I guess).

Ah, yes, I looked up that approved document a couple of years ago when I nearly bought a house in which I'd have wanted to add another toilet. Cheers for reminding me, I'll dig it up, but I doubt much of it will be relevant to this little job.

Pete

[Frank Erskine]

I had that problem a few years ago. Because of the tiny size of the bathroom (1970s ish) it was difficult to find a bath to replace the original chocolate brown (yuk!) one because of the boxed-in soil stack in the corner. I had an idea of using an air admittance ("Durgo"-type) valve fitted below the level of the bath so that I could fit a normal-sized bath. The local BCO confirmed that there would be no objection to that as neighbouring soil stacks were conventional so that there would be no problem venting the sewer down the street. However, the discharge from the wash-basin was higher than that (obviously), which isn't recommended for AAVs. In the end I succumbed to getting a local firm to refit the bathroom and they let the end of the new Armitage Shanks bath into the studding wall at the other end (just an inch or so)(towards the landing) and it doesn't look too bad...

[John Rumm]

Its rare to see a strap on boss used for a 4" soil connection - chances are it will be a proper branch fitting of some sort.

If in doubt, start by cutting out a section of pipe in the middle using a reciprocating saw. You can then unplug and reassemble the stack to your hearts content below the cut. Finally you can patch in the last bit of pipe with a rubber slip coupling or two.

Recip saw with a long hacksaw blade would probably work best if it is a plastic pipe.

The obvious one to avoid is having two branches facing each other at the same height. You don't want what you flush popping out the the plug hole in the bath!

[John Rumm]

Yup, its eminently doable. If you prepare carefully, use decent adhesive and grout, and take your time. Tools are fairly minimal. A good score and snap cutter, a small electric tile saw for the tricky cuts, a decent adhesive trowel (makes getting a level bed of adhesive much simpler than with those silly plastic things you get free in the tub), and a rubber faced grout float.

Last time I saw a job of about that size done professionally it cost about £450 IIRC - that was about three years ago though.

[Peter Johnson]

Do it yourself, take your time. Apply the grout with a grouting sponge. (Five years ago I paid to have my en suite done and did the bathroom myself. I can see where I've done it better, because I took longer, than the professionals and where they did it better because they had more experience but there's not much in it. )

[DavidM]

I agree with John about the tools, particularly a good adhesive trowel and a rubber faced grout float (not a sponge - it's harder to force the grout firmly into the joints, and is a lot slower to use). Use a slightly damp sponge to wipe down afterwards.

You'll also need a decent spirit level to get everything horizontal/vertical all around the room and some battens to nail/screw to the wall to tile up from, otherwise the tiles may slip down. Don't assume that anything in the room is vertical, horizontal or straight!

Setting out is everything, before you even open the tub of adhesive. Plan where the tiles go, both vertically and horizontally, so you don't end up with silly small gaps at corners, around window frames etc, and don't have very narrow bits to rim off tiles. Try and make cut tiles at each side of a wall/window reveal a similar width. Allow for out of true wall corners, windows and door.

On each wall draw two straight datum lines, one horizontal and one vertical, to work from. Make sure the horizontal one joins up with itself when you've gone around the room.

If you don't do the setting out properly, you WILL regret it later. Try and get a look at a few professionally done bathrooms and look at how the tiles are set out.

Take your time, you might take 3 or 4 times longer than a professional, but you can get a good finish and the result can be very satisfying.

(from a non professional tiler who's done it) David

[Pete Verdon]

OK, I guess one wouldn't want to tile upwards from a possibly not-horizontal floor. Is the idea that the batten is fixed with the top one tile-height from (some of) the floor, and then the bottom row of tiles is slotted in once the rest of the wall is fitted and secure?

I'll probably be replacing the floor anyway; I believe it's currently normal boards and certainly whatever it is it moves far too much to tile onto. (Not that that has stopped someone from trying, and the current tiles are mostly loose and/or cracked). Is it worth trying to get the floor completely horizontal (within tolerance, anyway) and then tiling up from it instead of a batten? This doesn't prevent me falling back to a batten if it turns out the finished floor isn't as flat as I'd hoped.

Incidentally, what *is* regarded as a sufficiently stable floor for tiling, on a normal timber first-floor structure? Just normal green chipboard, or is it best to add ply or something on top of that?

I'm considering including under-floor heating, not so much to keep my tootsies warm (I have no problem in bare feet with the various unheated tiled floors downstairs) but to evaporate off water left on the floor after a shower. For twenty years my Dad has gone nuts about manually drying off every surface in his bathroom - I'm not planning to build a full-on wet room, but neither do I want to worry about not leaving puddles. For the same sort of reason, I want to make the floor and walls totally impervious - actually as if it *were* a wet room. I've been looking at various membranes that go under the tiles - presumably these are needed because the grouted joints aren't actually 100% waterproof?

Is there a special technique for that? Naively, I'd allow for it by tiling towards such features rather than away from them, and then cutting the tiles in the final column to fit the gap that exists. Any other tips?

Pete

[John Rumm]

That depends on how they layout vertically. As Dave mentioned, you need to look at the fit of the tiles in both directions before committing yourself. Many people will try and position the tiles so as to get the fewest number of cuts - often this can be a mistake. You may find for example that a whole tile at the bottom means you need a 16th of one at the top, or the run out in the floor may be such that you would end up needing to make very fine cuts to keep things level. Its often better to "half and half" such situations - move the tile say half a tile down so that you have to cut all the top and all the bottom tiles, but you have nice workable sized bits to fix rather than slivers. Same can go with corners and window reveals. Work out what will look right and tile to that. If you must have a line that changes width along its length then its much better if it is not too narrow - makes it less obvious to the eye.

If you are using skirting or coving, then you have much more freedom to position, since the edges will be hidden.

Personally I would worry about tiling from the floor - that row can go in anytime and you can adjust for any unevenness as you do it. If it si well out of level then you may want to tru it up a bit by adding packers under the existing boards. Then screw 9mm WBP ply down over the boards and use a flexible floor tile glue to fix them. Make sure to screw it well - say every 6" (and make sure the screws are not just a fraction too long such that when you find the concealed central heating pipe that is pressed hard against the underside of the board, you end up nicking a pipe (DAMHIKIJDOK))

If the existing boards are 19mm then as above. If the existing floor is too bad you can always replace it with ply all over.

If you are expecting significant quantities of water (i.e. a wet room) then there is always the danger that you get a leak somewhere. For ordinary bathroom tiling however you can get more than satisfactory results without membranes.

A couple of tricks that help, is to not grout the corners and to use silicone here instead - since this is a place that any movement will open up a crack. In things like shower enclosures its worth using a waterproof backing board rather than plasterboard - you can also help by applying a full bed of adhesive and then ribbing the top, rather than just ribs with gaps. Use a waterproof glue obviously. Anytime you want to seal against a corner (say for a shower tray) leave at least a tile thickness space to get the sealant well into.

Again - keep any strips of cut tiles wider rather than narrower to minimise visible error.

If you need to go round wide pipes (i.e. soil pipes, boiler flues etc), then take this into account with your tile positioning - if you can get the pipe half way into two tiles it is much easier to cut to half circles than one full one.

Lithofin grout protector works well to keep grout looking clean and new. You apply it once when done, it soaks in without a trace, but adds polymer protection to the grout.

Straight cuts away from the edges of the tiles are easy with a good quality score and snap cutter. Fine slithers need doing with a tile saw though.

[Pete Verdon]

Thanks for all the advice so far.

I already have an electric tile saw from replacing a couple of tiles in the kitchen floor. Does a score&snap cutter have benefits over that for the simple cuts? I guess it might be faster?

Cheers,

Pete

[The Natural Philosopher]

That the only benefit I have found. Pro tilers using very cheap white tiles on more or less square walls can do the job faster, but I found score and snap to be a pain on larger harder more expensive tiles, resulting in many breakages, to the point where I only use the saw these days.

[DavidM]

I would in any case leave a slightly over sized gap between the bottom wall tile and the floor, and then finish with a bead of silicone forced well into the gap. If there's any water splashing around on the floor it's this join that most susceptible to movement and leaks.

I know I'm repeating myself, but do try and take a look at some professionally tiled bathrooms (NOT bathroom showrooms) and see how (and try and work out why) they have laid out the tiles in the way they have . Many prof tilers will tell you that setting out is the trickiest and most important part of the job, and it's worth trying to learn from their experience. [gets off soapbox] David

[stuart noble]

No, the idea of the batten is that the tiles below it can be measured and cut individually to allow for the floor not being level. If the batten is set well under a tile width, it's easy to snap cut the last line, even if they're slightly angled. Leaving yourself with a 5mm tapered cut isn't a good idea or, worse still, realising that the other end of the batten is in fact slightly higher than a tile width :-)

In the real world, most people start with a line along the top of the bath and work downwards where the wall becomes full height. Tiles don't slip far, and you can just shunt them up as you go. A couple of nails in the plaster is enough to keep them in place if you're having a break.

[stuart noble]

Much, much faster. No mess. Sits next to you rather than in the garden :-)

[John Rumm]

Much faster, & cleaner. If you need repeat cuts, you can probably do half a dozen a minute with a score and snap cutter. A dual action one like:

well enough for tiles up to 10mm. I find it exceedingly rare to break a tile using these. Some types of tile you can't cut with these - typically the softer stuff like travertine marble or anything else with a natural non consistent biscuit.

[Pete Verdon]

You don't need to repeat yourself - I agree it's a good idea :-)

I have at least one example to look at - my parents have recently spent many thousands on having their bathroom professionally done. As a whole it's not perfect (the design is compromised by Mum's insistence on fitting a bath where there isn't really space) but the tiling is f-ing immaculate.

I've been admiring it in general since deciding to do this job, but next time I'm there I'll have a specific look at how the setting-out has been done.

Pete