DIYbanter - View Single Post

(william) wrote in message . com...
Hi
I'm looking for some opinions on using cement based adhesive on gypsum
plastered (skimmed) drywall?
I'm doing my first paid tiling job (for a family member) she got all
the material the supplier knew where the tile was to be fitted
(plastered drywall) he supplied a cement based powdered adhesive
It says on the bag "not to be used on gypsum based plaster" I asked
him about this and he said its fine to use it he has sold tons of the
stuff and never had a problem.

I guess thats how easy it is to sell something to some folk.

My sister in law (the client) is happy enough to use it she says he
should know what he is talking about, as it is his job.

if only that translated into reality. It should, but doesnt.
Especially when it comes to building.

To make things worse there is a shower that is to be tiled and the
substrate in the shower area is skimmed plasterboard (he says it is
perfect for this as it is a flexible adhesive).

good lord, worst option for that. (Apart from dried porridge.) Plaster
and cement react chemically if they get wet, and the result is they
come apart. You dont use cement on plaster.

I want to use ready mixed adhesive but am a bit unsure because the
walls are studded walls not solid block walls and they will move a
little.
The supplier thinks I'm a donkey

but not for the reason you think.

and my client thinks I'm over
reacting.

is your client skilled or experienced in the business? Client naivety
is normal.

But it says on the bag it's not suitable.

indeed... what does that tell you?

And I have researched it on the web and found something about some
reaction between cement and gypsum.
Should I just do the job with what he supplied and keep my opinions to
myself?

Your call - seems daft to me though to do a job for a family member
that all falls off in 6 months.

NT