Help!
There has been some confusion over whether we can seal our slate tiles as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????

Would appreciate answers very soon

Thanks

Martin

On Tue, 24 Feb 2004 23:58:41 -0000, "Martin"
wrote:

Help!
There has been some confusion over whether we can seal our slate tiles as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????

Would appreciate answers very soon

Thanks

Martin



The advice I had from several sources when a screed was laid in my
conservatory on top of a concrete base was to wait a week after the
oversite concrete before screeding and then 3 weeks after that before
laying slate.

You should really wait before laying the slate, never mind about
sealing. Curing of the screed is mainly a chemical process, but if
you are too fast off the mark in laying the tiles, I understand from a
professional who did that there is a risk of the slates either lifting
or cracking.

It's a case of being patient.....


..andy

To email, substitute .nospam with .gl

"Andy Hall" wrote in message
...
On Tue, 24 Feb 2004 23:58:41 -0000, "Martin"
wrote:

Help!
There has been some confusion over whether we can seal our slate tiles
as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain
stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????

Would appreciate answers very soon

Thanks

Martin



The advice I had from several sources when a screed was laid in my
conservatory on top of a concrete base was to wait a week after the
oversite concrete before screeding and then 3 weeks after that before
laying slate.

You should really wait before laying the slate, never mind about
sealing. Curing of the screed is mainly a chemical process, but if
you are too fast off the mark in laying the tiles, I understand from a
professional who did that there is a risk of the slates either lifting
or cracking.

It's a case of being patient.....

Thanks for your reply Andy. Unfortunately the slate was laid today! We
received advise from Stonell that it be OK to lay the slate on the screed
after only a few days as long as we don't seal them. From that advise I
assume their reasoning is that they think that screed gives out moisture and
as long as the slate isn't sealed and grouted moisture will be able to
escape from the screed allowing it to dry- is this totally incorrect? Can we
claim from Stonell if the tiles crack later? Help!!!!! Also the instructions
on the adhesive and it says 3 weeks should be allowed before tiling after
screed is laid! Is Stonell right or everyone else!? My builder is intending
to stain stop the tiles and grout tomorrow should I tell him to wait????

Thanks

Martin

Thanks for your reply Andy. Unfortunately the slate was laid today! We
received advise from Stonell that it be OK to lay the slate on the screed
after only a few days as long as we don't seal them.

I'm surprised in a way, because they supplied my slate and were one of
the sources of advice to wait three weeks. Oh well.

From that advise I
assume their reasoning is that they think that screed gives out moisture and
as long as the slate isn't sealed and grouted moisture will be able to
escape from the screed allowing it to dry- is this totally incorrect?

the curing process is predominantly a chemical one rather than a
drying out one.

My concern is that the moisture has been removed from the screed
artificially and the curing may not complete properly. I believe,
but would need to check, that with a dryish mix like a screed, that
the risk from too rapid drying is that it can crack or in the worst
case crumble.


Can we
claim from Stonell if the tiles crack later?

I think that that would be tough.

Help!!!!! Also the instructions
on the adhesive and it says 3 weeks should be allowed before tiling after
screed is laid! Is Stonell right or everyone else!?

Three weeks is undoubtedly a conservative figure and you may get away
with less.

My builder is intending
to stain stop the tiles and grout tomorrow should I tell him to wait????

It probably is not going to make a huge difference at this point. If
the room has been artificially dried then most of what moisture there
was will have gone.

I suppose what you could do is to leave the slate unsealed and
ungrouted for the moment and cover it with paper or something to
protect it for a week or so. Then see what happens and go from there.




Thanks

Martin



..andy

To email, substitute .nospam with .gl

What is this screed? How thick is it? Those I've used to a depth of half
inch you can walk on in 3-4 hours with no risk of subsequent cracking.
Expensive stuff over a large area though.

Martin wrote:

Help!
There has been some confusion over whether we can seal our slate tiles as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????



None.

Screed sets as much as dries.

Slate is more or less impervious anyway. The grout will slowly leak
moisture out, even if 'waterproofed'

Nothing will be harmed by having a higher floor moisture content under a
semi-impervious layer, for a year or two till it all equalises



Would appreciate answers very soon

Thanks

Martin

Andy Hall wrote:

On Tue, 24 Feb 2004 23:58:41 -0000, "Martin"
wrote:


Help!
There has been some confusion over whether we can seal our slate tiles as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????

Would appreciate answers very soon

Thanks

Martin




The advice I had from several sources when a screed was laid in my
conservatory on top of a concrete base was to wait a week after the
oversite concrete before screeding and then 3 weeks after that before
laying slate.

You should really wait before laying the slate, never mind about
sealing. Curing of the screed is mainly a chemical process, but if
you are too fast off the mark in laying the tiles, I understand from a
professional who did that there is a risk of the slates either lifting
or cracking.


That IS true. My screed cracked - quite badly in places - and shrunk.
That took a few weeks

Cracks can be filled believe it or not - by pouring gallons (lioterraly)
of diluted PVA down them. That stabilises the screed and prevents movement.

Then use a reasonably thick bed of slate cement.



It's a case of being patient.....


.andy

To email, substitute .nospam with .gl

"The Natural Philosopher" wrote in message
...
Martin wrote:

Help!
There has been some confusion over whether we can seal our slate tiles
as
our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain
stopped.
What problems would be encountered if we seal it and the screed hasn't
dried????



None.

Screed sets as much as dries.

Slate is more or less impervious anyway. The grout will slowly leak
moisture out, even if 'waterproofed'

Nothing will be harmed by having a higher floor moisture content under a
semi-impervious layer, for a year or two till it all equalises

what is equalising???

Martin wrote:

Thanks for your reply Andy. Unfortunately the slate was laid today! We
received advise from Stonell that it be OK to lay the slate on the screed
after only a few days as long as we don't seal them. From that advise I
assume their reasoning is that they think that screed gives out moisture and
as long as the slate isn't sealed and grouted moisture will be able to
escape from the screed allowing it to dry- is this totally incorrect? Can we
claim from Stonell if the tiles crack later? Help!!!!! Also the instructions
on the adhesive and it says 3 weeks should be allowed before tiling after
screed is laid! Is Stonell right or everyone else!? My builder is intending
to stain stop the tiles and grout tomorrow should I tell him to wait????



I think teh greatest danger is not the dampness of the screed being
unable to escape, but the danger of the screed shrinking and causing
loose slates etc.

I would satin stop it immediately, but hold off grouting a week or two.
If a slate crack or lifts, you can replace it fairly easily. (Car body
filer is a superb tile ahesive BTW, just ***ing expensive....)


Thanks

Martin

stuart noble wrote:

What is this screed? How thick is it? Those I've used to a depth of half
inch you can walk on in 3-4 hours with no risk of subsequent cracking.
Expensive stuff over a large area though.




1/2" aint a screed. thats a skim!

Screed is generally 3-4" You can walk on it after about 24 hours, but
full strength and shrinkage builds up over a week or two.

Martin wrote:

"The Natural Philosopher" wrote in message
...

Martin wrote:


Help!
There has been some confusion over whether we can seal our slate tiles

as

our screed has been only laid for 5 days, would it really be a problem
sealing the tiles as we can't grout till the tiles are sealed/stain

stopped.

What problems would be encountered if we seal it and the screed hasn't
dried????



None.

Screed sets as much as dries.

Slate is more or less impervious anyway. The grout will slowly leak
moisture out, even if 'waterproofed'

Nothing will be harmed by having a higher floor moisture content under a
semi-impervious layer, for a year or two till it all equalises


what is equalising???



Sorry - mean that the screed and the room humidity levels reach equilibrium.

Look never mind the damp under the slate. Its probably a Good Thing to
slow the drying out of the screed anyway. The greatest danger is laying
slate over an unstable structure. Or getting staining on the slate due
to damp migrating upwards. But I doubt that.

I reckon you will get way with it, but, as I said last post, maybe delay
teh grouting a few weeks in case a slate comes unstuck, or cracks.

The Natural Philosopher wrote in message ...
1/2" aint a screed. thats a skim!
Well, there's a source of confusion then. Screed in the flooring trade these
days refers to the self levelling variety, which is applied to a max depth
of half inch. Excellent stuff for bringing old concrete floors up to
standard quickly but too expensive for levelling.

stuart noble wrote:

The Natural Philosopher wrote in message ...

1/2" aint a screed. thats a skim!

Well, there's a source of confusion then. Screed in the flooring trade these
days refers to the self levelling variety, which is applied to a max depth
of half inch. Excellent stuff for bringing old concrete floors up to
standard quickly but too expensive for levelling.




Mm. Screed in the building trade is not. That's just a self levelling skim.

I'd say your floorers have hijacked the wrong word.