I have just had my walls in my bathroom coated with bonding plaster. I
am getting conflicting advice as to whether it is ok to tile directly
on this surface. Does anyone know whether it is ok to do this? And if
not does this mean I have to get the walls skimmed. Any help will be
extremely appreciated as I am completely stuck so to speak!

In article .com,
writes:
I have just had my walls in my bathroom coated with bonding plaster. I
am getting conflicting advice as to whether it is ok to tile directly
on this surface. Does anyone know whether it is ok to do this? And if
not does this mean I have to get the walls skimmed. Any help will be
extremely appreciated as I am completely stuck so to speak!

Tiling onto bonding coat is fine.

--
Andrew Gabriel

Andrew Gabriel wrote:

Tiling onto bonding coat is fine.


It may well be, but it isn't recommended practice.

For instance, http://www.tiles.org.uk/help/answer-gypsum.shtml

In article ,
Bolted writes:
Andrew Gabriel wrote:

Tiling onto bonding coat is fine.


It may well be, but it isn't recommended practice.

For instance, http://www.tiles.org.uk/help/answer-gypsum.shtml

A couple of differences I do from that article which might be
relevant... I never use ready mixed adhesive or grout, and in
the case of something like a shower, I use a waterproofing
admix in the grout (which also helps it stay clean, as well
as protecting the backing from moisture).

--
Andrew Gabriel

Andrew Gabriel wrote:

A couple of differences I do from that article which might be
relevant... I never use ready mixed adhesive or grout

That's a deliberate statement on their part because of the ettringite
problem between cement and gypsum - that's why they are recommending the
glue type tub gear.

Maybe Biscem is more persuasive? Page 7 of this:
http://www.biscem.co.uk/downloads/Bi...ilingGuide.pdf


, and in
the case of something like a shower, I use a waterproofing
admix in the grout (which also helps it stay clean, as well
as protecting the backing from moisture).

I use epoxy in showers.

wrote:
I have just had my walls in my bathroom coated with bonding plaster. I
am getting conflicting advice as to whether it is ok to tile directly
on this surface. Does anyone know whether it is ok to do this? And if
not does this mean I have to get the walls skimmed. Any help will be
extremely appreciated as I am completely stuck so to speak!

Its fine. It will suck the cement pretty hard though. Some people like
to seal with PVA..

wrote:

I have just had my walls in my bathroom coated with bonding plaster. I
am getting conflicting advice as to whether it is ok to tile directly
on this surface. Does anyone know whether it is ok to do this? And if
not does this mean I have to get the walls skimmed. Any help will be
extremely appreciated as I am completely stuck so to speak!

Yes you can (as long as it is flat enough!), I have done it several
times without any problems.

--
Cheers,

John.

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wrote:
I have just had my walls in my bathroom coated with bonding plaster. I
am getting conflicting advice as to whether it is ok to tile directly
on this surface. Does anyone know whether it is ok to do this? And if
not does this mean I have to get the walls skimmed. Any help will be
extremely appreciated as I am completely stuck so to speak!
Done it several times. Always PVA'd it first, since surface can be a
little dusty.
Simon.

The Natural Philosopher wrote:

Its fine. It will suck the cement pretty hard though. Some people like
to seal with PVA..


Hadn't you better warn him that you also say that it is fine to tile
onto chipboard on the basis that most of yours were fine and only a
couple lifted and needed to be replaced with a bit of new sub-floor, or
whatever that story was?

It's a bodge, and not recommended. Seal it well. The tile adhesive
manufacturers almost universally say do not use PVA but a proprietary
acrylic sealer. This may be because they want to sell their proprietary
products, but they are insistent on this point.

Preferably use tub gear to avoid future etrringite problems, and make
sure your grout is waterproof - epoxy preferably (ignore the scare
stories, it is easy to use) or a powder grout with a waterproofing
admixture as someone else suggested. 90 something times out of a
hundred it will probably be fine anyway, but don't expect any sympathy
from the adhesive manufacturer if they do fall off and you haven't
followed their instructions.

Next time ask for a sand/cement render base if you are tiling over it.

Thanks for everyone who has given me help on this. I have just
completed it directly on the bonding, I'll let you know if any fall off!