how to tile woodchipped plasterboard ?

Steam the woodchip off and tile over. If it won't come off in patches, don't worry. Tile on top of the good bits using a thick enough bed to line everything up properly. Strings and levels help in this.

As also does a batten nailed to the wall a little above the bottom, to get a level staring point.

Thanks, Nat Phil. I am surprised to hear that it will be possible to steam the woodchip off. I presumed because it was silk-based the steam wouldn't be able to get through the paper and loosen the glue. But I have worried about this too much?

Must research steamers!

Thanks too for hints re. making sure the lines are straight.

Eddy.

Oh, I almost forgot. Is it really OK to tile straight onto plasterboard? Is the papery surface of the plasterboard able to form a strong bond with the tile-adhesive?

Eddy.

Yup. You can give it a coat of dilute PVA first if you need to consolidate the surface should it get damaged getting the paper off.

Huh? must be different woodchip to what I used to use then.

Very much soggy paper that was.

Its fine.

Very good idea, John. Thanks.

Eddy.

Err. Sorry. Didn't mean to say the paper was silk-based, but the coats of paint that seal it are silk-based (and probably oil-based). Will a steamer still work? I can imagine it easily lifting woodchip which has only been painted with emulsion.

Eddy.

should be OK..direct steam under the edge of the paper rather than the surface.

Remember, you are not dong a pukka job here, merely making sure that anything loose comes off, and anything crumbly is stabilised.

You could try wet sponges and a scraper just as easily I suspect.

It doesn't take much to hold tiles (once grouted) up, by the way..think of them as a very thin brick wall, that just needs to be prevented from buckling by a light force sideways.. there is very little shear force on the cement.

You /may/ need to lightly score the surface of the paint with a stanley knife. Other than that, I prefer removing paper with hot water and lots of patience (but that's just me).

Thanks, Nat Phil. Am just rather good at visualizing the worst: a wall of tiles come tumbling down while someone is sitting on the loo! Hence, concern about getting a good bond between tiles and the wall surface.

Eddy.

Good idea, Martin. Thanks. Yes, I reckon I need to think slow hard work, rather than woodchip just coming away with total obedience!

Eddy.

It comes off more easily if you penetrate the paper first to let the steam get behind it, eg with one of these things:

Thanks, Matt. Wow, what a clever implement! Brilliant invention. You "scrub" the wall with it, easily making 1000s of tiny holes to let the steam or removal solution get behind the paper. Amazing. Wish I could borrow one. Only need it for the one small bathroom.

Eddy.

One of those decent bladed scrapers makes a big difference on woodchip.

e.g.