How long to leave a screeded floor before tiling?

100 mm screed with underfloor wet central heating embedded in it. As I
see it there are two issues: a/ the screed 'curing' ie hydrating the cement,
and b/ drying out any excess moisture. Under the screed is 100mm celotex and
a membrane, so moisture will be trapped between impermeable tiles and
impermeable membrane. I do have a large industrial de-humidifier to help.

AWEM

Andrew Mawson wrote:

How long to leave a screeded floor before tiling?

100 mm screed with underfloor wet central heating embedded in it. As I
see it there are two issues: a/ the screed 'curing' ie hydrating the
cement, and b/ drying out any excess moisture. Under the screed is 100mm
celotex and a membrane, so moisture will be trapped between impermeable
tiles and impermeable membrane. I do have a large industrial de-humidifier
to help.

AWEM

Week per inch thick I *think* - if the air is warm - at least for a wet lay.

Partly depends how wet/dry the screed was. Might be somewhat less for a
proper dry laid screed.

--
Tim Watts Personal Blog: http://www.dionic.net/tim/

"It would be better to live under robber barons than under omnipotent
moral busybodies."

On Oct 30, 7:01*pm, "Andrew Mawson"
wrote:
How long to leave a screeded floor before tiling?

100 mm screed with underfloor * * wet central heating embedded in it. As I
see it there are two issues: a/ the screed 'curing' ie hydrating the cement,
and b/ drying out any excess moisture. Under the screed is 100mm celotex and
a membrane, so moisture will be trapped between impermeable tiles and
impermeable membrane. I do have a large industrial de-humidifier to help.

AWEM

Once it is cured, you can accelerate the process by closing the room
up and running a dehumidifier.
If you have a cheapo damp meter you can keep a check on progress. (The
sort with two spikes you stick in). Even so,likely to take a couple of
weeks. Room must be airtight and avoid opening door sexcept to remove
water tray from dehumidifier.

This is usually left until all "wet trade" work is done so that the
whole room can be dried out at once.

"harry" wrote in message
...

On Oct 30, 7:01 pm, "Andrew Mawson"
wrote:
How long to leave a screeded floor before tiling?

100 mm screed with underfloor wet central heating embedded in it. As
I
see it there are two issues: a/ the screed 'curing' ie hydrating the
cement,
and b/ drying out any excess moisture. Under the screed is 100mm celotex
and
a membrane, so moisture will be trapped between impermeable tiles and
impermeable membrane. I do have a large industrial de-humidifier to help.

AWEM

Once it is cured, you can accelerate the process by closing the room
up and running a dehumidifier.
If you have a cheapo damp meter you can keep a check on progress. (The
sort with two spikes you stick in). Even so,likely to take a couple of
weeks. Room must be airtight and avoid opening door sexcept to remove
water tray from dehumidifier.

This is usually left until all "wet trade" work is done so that the
whole room can be dried out at once.


Yes, Plasterers are plastering as I type (Wednesday), and a second
de-humidifier has been hired for Friday when the 5 cu M of screed go down.
(50 sq M area) - the screed will have fibres in it to hopefully prevent too
much drying out cracking.

AWEM

On 31/10/12 09:10, harry wrote:
On Oct 30, 7:01 pm, "Andrew Mawson"
wrote:
How long to leave a screeded floor before tiling?

100 mm screed with underfloor wet central heating embedded in it. As I
see it there are two issues: a/ the screed 'curing' ie hydrating the cement,
and b/ drying out any excess moisture. Under the screed is 100mm celotex and
a membrane, so moisture will be trapped between impermeable tiles and
impermeable membrane. I do have a large industrial de-humidifier to help.

AWEM

Once it is cured, you can accelerate the process by closing the room
up and running a dehumidifier.
If you have a cheapo damp meter you can keep a check on progress. (The
sort with two spikes you stick in). Even so,likely to take a couple of
weeks. Room must be airtight and avoid opening door sexcept to remove
water tray from dehumidifier.

This is usually left until all "wet trade" work is done so that the
whole room can be dried out at once.


Frankly don't wait period. The tiling process puts massive amounts of
wet into the screed.

Try to NOT use the UFH at high temps until the thing has dried out a bit.

And wait before you grout.



--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

On 30/10/2012 19:01, Andrew Mawson wrote:
How long to leave a screeded floor before tiling?

100 mm screed with underfloor wet central heating embedded in it. As
I see it there are two issues: a/ the screed 'curing' ie hydrating the
cement, and b/ drying out any excess moisture. Under the screed is 100mm
celotex and a membrane, so moisture will be trapped between impermeable
tiles and impermeable membrane. I do have a large industrial
de-humidifier to help.

Some boilers/control systems (e.g. Vaillant) have screed drying
programs, that warm that zone slowly and progressively following a
program of warmer and cooler heating sessions over a month to accelerate
the process.

--
Cheers,

John.

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