I've got a small cloakroom floor consisting of concrete blocks with an
up to 2" covering of sand and cement. How long do I have to wait before
I can drill and plug it to install a studded partition?

TIA.

--
Frank
(Beware of spam trap - remove the negative)

F wrote:
I've got a small cloakroom floor consisting of concrete blocks with an
up to 2" covering of sand and cement. How long do I have to wait
before I can drill and plug it to install a studded partition?

TIA.

You can fix to it after it's been down a week, although you should fix to
the sides and top primarilly

In article ,
F writes:
I've got a small cloakroom floor consisting of concrete blocks with an
up to 2" covering of sand and cement. How long do I have to wait before
I can drill and plug it to install a studded partition?

It goes off in 2 stages. First takes 24-48 hours, when it will
feel set, but doesn't have much strength. Second stage takes
weeks. I would suggest that unless you are going to wait a few
weeks, you drill right through into the concrete blocks. If
you try to get any kind of grip with plugs in the sand and
cement before then, it will likely crumble when the plug
expands to grip it.

--
Andrew Gabriel

F wrote:
I've got a small cloakroom floor consisting of concrete blocks with an
up to 2" covering of sand and cement. How long do I have to wait before
I can drill and plug it to install a studded partition?

TIA.

At least 24 hours, 60 preferably. depending on temperature

On 16/11/2006 22:54 The Natural Philosopher wrote:

At least 24 hours, 60 preferably. depending on temperature

Room temperature...

--
Frank
(Beware of spam trap - remove the negative)

F wrote:
On 16/11/2006 22:54 The Natural Philosopher wrote:

At least 24 hours, 60 preferably. depending on temperature

Room temperature...


Well 24 hours for it to be safe to walk on...BUT it may take a week or
two to be full strength.

"F" wrote in message
...
I've got a small cloakroom floor consisting of concrete blocks with an up
to 2" covering of sand and cement. How long do I have to wait before I can
drill and plug it to install a studded partition?

TIA.
Screed is a surface leveller not a structural layer - don't fix to it ...
fix through it to floor below.

Screed should have a week per inch of thickness .... if you want to go
quicker give it a soaking with water (it sets by chemical action not drying)

You can sprinkle the surface with a concrete hardener (easy availability)
give a very hard dust free surface if that is needed)

Rely on the vertical fixing of stud partition for fixing, and just count on
anything to screed as a bonus - but don't rely on it for mechanical fixing.

Rick Hughes wrote:
"F" wrote in message
...
I've got a small cloakroom floor consisting of concrete blocks with an up
to 2" covering of sand and cement. How long do I have to wait before I can
drill and plug it to install a studded partition?

TIA.
Screed is a surface leveller not a structural layer - don't fix to it ...
fix through it to floor below.

Haha. That's like saying plasterboard isn't structural, or breeze block.

I can assure you that going through 4" of screed, 2 " of polystrene and
into precast concrete beams is not an option here..

The screed is FAIRLY structural.

Its a cheap gap filler, as its mainly sand, with enough cement to render
it fairly solid. How solid depends on how much cement of course.

Screed should have a week per inch of thickness .... if you want to go
quicker give it a soaking with water (it sets by chemical action not drying)

You can sprinkle the surface with a concrete hardener (easy availability)
give a very hard dust free surface if that is needed)

Paint it with dilute PVA.


Rely on the vertical fixing of stud partition for fixing, and just count on
anything to screed as a bonus - but don't rely on it for mechanical fixing.



You can,. if its deep enough and has more than a whiff of cement.

The Natural Philosopher wrote:

The screed is FAIRLY structural.#]

Screed is classed non- structural by building regs.

You can sprinkle the surface with a concrete hardener (easy availability)
give a very hard dust free surface if that is needed)

Paint it with dilute PVA.


This will do very little other than seal it, it will not harden it.



The purpose of screed is to take the sub floor - concrete pour, beams
etc. .... and top it off to provide a level firm surface for final
finish, often to an exact DPM point, it has and provides no structural
strength.


By all means use it as an additional fixing point to help restrain, but
do not rely on it.

I have 230m2 of 75mm thick fibre reinforced screed on my ground floor,
all treated with surface hardener - and not a single thing has been
fixed to it other than tiles - all Wood floor is laid floating
I would not put a nail or screw into the screed.

Osprey wrote:
The Natural Philosopher wrote:

The screed is FAIRLY structural.#]

Screed is classed non- structural by building regs.

That is not the pint. The point is that screed has strength..and takes
weight well.

You can sprinkle the surface with a concrete hardener (easy availability)
give a very hard dust free surface if that is needed)

Paint it with dilute PVA.


This will do very little other than seal it, it will not harden it.


It hardens the surface considerably. It even connects cracked slabs
together..I've done it. PVA on screed will produce an almost completely
dust free surface.



The purpose of screed is to take the sub floor - concrete pour, beams
etc. .... and top it off to provide a level firm

Firm=structural in ordinaryspeek.

surface for final
finish, often to an exact DPM point, it has and provides no structural
strength.


By all means use it as an additional fixing point to help restrain, but
do not rely on it.

I have 230m2 of 75mm thick fibre reinforced screed on my ground floor,
all treated with surface hardener - and not a single thing has been
fixed to it other than tiles - all Wood floor is laid floating
I would not put a nail or screw into the screed.


Well I have the same, but I have mounted toilets and bits of studwork on
it. Its OK if you accept that - like plasterboard - its got very low
tensile strength, abut isn't bad in compression and shear.

The Natural Philosopher wrote:

Well I have the same, but I have mounted toilets and bits of studwork on
it. Its OK if you accept that - like plasterboard - its got very low
tensile strength, abut isn't bad in compression and shear.


Well - we agree on this partly ... Screed is a levelling finish, and is
good in compression ... however it is not good for any edge, shear,
tensile etc.
Don't believe me, pull back a carpet and look at screed around stairs
for example - it will more than likely have large cracks in it.

As for PVA giving it hardness & increased strength ... hmmm ...if that
was the case don't you think that this would be standard in the
building trade ? rather than purpse designed hardeners .. and it is not
just a selling ploy, they are a totally different formulation.
PVA give a sealed finish ... not a hardened one.

Screed is certainly not good for holding screws ... hole edge easily
crumbles, very low pull out strength.
If I needed to fix a sole plate of a studded wall and couldn't screw
through to concrete below - then I would glue the wood along it's
length to the screed .. and then just put a few screws into screed act
as location & reinforcing fixing pins.

I spent a long time working on sites - one of the easily damaged items
was floor screed, nice flat finish easily ruined for example by a
carpenter dragging a saw horse over it.

Anyway - advice given, ... the original poster can take their choice
over whether to consider screed as a suitable medium for a secure
mechanical fixing or not.

Osprey wrote:
The Natural Philosopher wrote:

Well I have the same, but I have mounted toilets and bits of studwork on
it. Its OK if you accept that - like plasterboard - its got very low
tensile strength, abut isn't bad in compression and shear.


Well - we agree on this partly ... Screed is a levelling finish, and is
good in compression ... however it is not good for any edge, shear,
tensile etc.
Don't believe me, pull back a carpet and look at screed around stairs
for example - it will more than likely have large cracks in it.

As for PVA giving it hardness & increased strength ... hmmm ...if that
was the case don't you think that this would be standard in the
building trade ? rather than purpse designed hardeners .. and it is not
just a selling ploy, they are a totally different formulation.
PVA give a sealed finish ... not a hardened one.

Screed is certainly not good for holding screws ... hole edge easily
crumbles, very low pull out strength.
If I needed to fix a sole plate of a studded wall and couldn't screw
through to concrete below - then I would glue the wood along it's
length to the screed .. and then just put a few screws into screed act
as location & reinforcing fixing pins.

I spent a long time working on sites - one of the easily damaged items
was floor screed, nice flat finish easily ruined for example by a
carpenter dragging a saw horse over it.

Anyway - advice given, ... the original poster can take their choice
over whether to consider screed as a suitable medium for a secure
mechanical fixing or not.


Might be helpful to establish what exactly you mean by "screed". The
latex stuff?