My downstairs bog job

[GMM]

Somehow, the smaller the room, the more tricky the job is=85

So I was about to continue tiling from my hallway into the downstairs bog and put electric undertile heating in (B&Q=92s sale nailed that decision) when I read the instructions: =93Electric UFH must be laid in flexible tile adhesive=94. Off to get some flexible and this says =93maximum depth 4mm=94. Now, my existing level is about 10mm above the floor (I know it=92s a lot but I was trying to level it out!). Hmm=85..time for a layer of floor levelling compund. The bag says 20kg covers 4.7sqm to a depth of 2.5mm. The floor=92s about 2.5sqm, so that should make nearly 5mm =96 about right. Mixed it up, spread it out and=85.it=92s about 2mm, well in the area that it covered, at least.

So: What does the panel think? Should I do another spread of FLC and hope that makes it up about as far as I need, forget the instructions and lay in rapid set adhesive or do something else?

Three little supplementaries here (while I=92m on!).

First, the waste pipe from the sink (1 =BC inch copper) disappears into the floor. Having taken the sink off, the pipe just lifted out of the hole (can see so ceramic down there, so it=92s not just seeping under the house!). I was thinking of fixing the new one with a good splodge of silicone, but I wonder if there=92s anything I should bear in mind / a more elegant solution?

Second, because this bog is a single storey extension to the house it was never plumbed for hot water (it=92d be a bugger to pipe to and the hot would never get there before you turned the tap off), so I want to rectify this with the job. It looks like there was once an over-sink heater as there=92s an fcu there, but this was gone before I got the place. I was thinking of a small electric heater in a vanity unit under the sink and have seen a few from furtling around at TLC=92s site etc. These are hardly cheap (especially with the special taps etc etc) so I was wondering if anyone had a clever alternative practical and good looking suggestion for this.

I had been wondering if I could manage something solar as there=92s a flat roof above, but it faces northwest, so it only gets the sun in the afternoon and, due to the local rules, I could only lay any kind of panel flat on the roof and not tilt it. Nonetheless, if there was a way of collecting a few litres of warmish water, it would do the job.

Third, one wall of this bog is plasterboarded and skimmed on the inside and plywood on the outside. I haven=92t investigated the thickness yet, but there seems to be some fibreglass between the two. I don=92t want to disturb the inside wall, but can get at the outside easily enough. Depending on the space available, I was thinking a sheet of kingspan might be a good idea in this cavity. Does anyone have any thoughts on this?

Thanks people!

[The Natural Philosopher]

Oh Id use ordinray rapid set to build up the level and thn lay flexi on top of that.

The trouble with flexi is, that it slupms..in thick beds.

Try also Ardurit flexi. Mixed stiff its not too bad.

sounds good to me.

Id say forget it in this country.

run a proper insulated hot water pipe of smallish bore, which will not contain so much cold water that you need to run a gallon before getting some hot..

If you use flexible pushfit its not too hard to route in whatever cavities you can find, or even ahem..under the tiles?

If its fiberglassed, the actual gais from going to kingspan will not be huge.

[GMM]

Indeed, which is why I'm keen to get the level right ! I used FLC as it's an easy (-ish) way to get the whole thing level, although it looks like it would take a few goes to bring it up as far as I need.

I've had my eye open for Ardurit stuff, since everyone seems to say it's the business, but have never seen it anywhere around here (Birmingham, so hardly out of the way). I wonder if there's a special code-word for places to bring it out from under the counter.....

[The Natural Philosopher]

Its made here.. so the local independent BM's actually stock it.

Try the main website and call em to see who stocks it in your area.. I think there is some advice on using it there as well.

[Mr Fuxit]

Connect the present cold water supply to your hot water supply. Then, after you've used the loo, you flush, and the cistern fills with the standing cold water which will reduce the time you have to wait for hot water. IYSWIM

[Man at B&Q]

Have you really thought this through?

What happens when you have visitors and the loo gets flushed a few times in succession? You now (a) waste a lot of hot water flushing the loo and (b) have to set the temp of the hot water such that no one can scold themselves which will have a knock on effect for the rest of the house (unless you also add a blending valve).

MBQ

[Rod]

Have you considered a small bore pipe - something like 10mm? It always looks like France is entirely plumbed with such stuff snaking round the place. Much easier to fit and hide than even 15mm. And, with it having such a small cross section, hot water will get through considerably more quickly than with larger bore.

Probably be best if you have reasonable HW pressure and are content for relatively low flow rate (just for hands?).

And you would, of course, lose quite a bit of heat from water standing in the pipe after use.

[<me9]

But less than from a fatter pipe.

[Rod]

And even less if well insulated. :-)

I'd guess it depends on intensity of use. If used a lot, OP wouldn't have much problem. If used hardly at all, losses would be small in total quantity.

[NOSPAMnet]

"Scold themselves?" ...as in looking in the mirror and shouting " You naughty naughty boy" or as in sitting on the loo bare-assed and then flushing the loo...hardly likely that is it ?

But seriously ,I agree that somehow he needs to get a proper hot and cold supply to the bathroom regardless of how difficult it might be . Others have suggested a way .

[GMM]

As usual, a lively set of ideas. I'll probably scold myself for even thinking about starting this job soon!

I had rather discounted the idea of running any kind of feed from the dhw simply because of the length of the run (probably about 40 feet in old money) and the difficulty of getting it there as I didn't really want to have to rip up the flat roof and drill through concrete lintels. Clearly the suggestion of using a smaller bore would give less of a delay in delivering the goods, although I have a feeling that it would still take a litre or two before it ran warm, by which time the user of said facility would be long gone, with cold damp hands. Perhaps it's time for a few experiments, before shelling out a fortune for the heater. Either that or, in the best and noblest traditions of this group, get at it with an angle grinder......