Just a possible future project at the moment...

I'm considering both improving the flatness and increasing the floor
level of my garage by screeding it. It is a little uneven due to the
fact that I very slightly underestimated the quantity of concrete
needed, when I originally laid it many years ago - which left it a
little rough finished at one end.

It could also do with the original floor level to be increased by about
1/2", to improve its resistance to flooding. The later due to a clay
sub soil holding water in extremely heavy periods of rainfall. There
was just a slight ingress a few weeks ago, which I would like to
resolve.

The floor area is 24' x 12'. I have seen screeding laid on top of
concrete to produce a good smooth finish, but how thin could this be
laid? How do you make a screed mix? Once dry, would it be waterproof on
might it allow moisture to track through it?

Any other ideas what to use instead? The finish will have to be fairly
rugged, able to cope with the weight of cars and their
maintenance/repairs.

Thanks for any replies.





--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

Harry Bloomfield wrote:
Just a possible future project at the moment...

I'm considering both improving the flatness and increasing the floor
level of my garage by screeding it. It is a little uneven due to the
fact that I very slightly underestimated the quantity of concrete
needed, when I originally laid it many years ago - which left it a
little rough finished at one end.

It could also do with the original floor level to be increased by about
1/2", to improve its resistance to flooding. The later due to a clay
sub soil holding water in extremely heavy periods of rainfall. There
was just a slight ingress a few weeks ago, which I would like to
resolve.

The floor area is 24' x 12'. I have seen screeding laid on top of
concrete to produce a good smooth finish, but how thin could this be
laid? How do you make a screed mix? Once dry, would it be waterproof on
might it allow moisture to track through it?

Any other ideas what to use instead? The finish will have to be fairly
rugged, able to cope with the weight of cars and their
maintenance/repairs.

Floor screeds are about an inch thick. Why not run it an inch to 2
inches at the back so that any water flows straight out?

Make it about six to one very coarse sand and cement. Wet the floor and
lay it on tilt fillets or raised batons. When you finish a section
remove the fillet and fill in the space.

When it is hard enough to walk on (maybe 6 hours or more, maybe with a
ply sheet under you) go over it with your steel trowel to polish it. It
brings the cement up to the surface and seals it.

You will need something at the edge to take the shock as the car hits
the floor. A strip of triangular section will do.

Google is playing up again maybe causing double posts. If it irks, tell
the buggers.

On 13 Dec 2006 15:13:34 -0800 Weatherlawyer wrote :
Floor screeds are about an inch thick. Why not run it an inch to 2
inches at the back so that any water flows straight out?

Make it about six to one very coarse sand and cement. Wet the floor
and lay it on tilt fillets or raised batons. When you finish a
section remove the fillet and fill in the space.

IME the usual spec for screed is 1:3, 50mm thick. I doubt whether 1:6
with a car being driven over it would last.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk

Tony Bryer wrote:
On 13 Dec 2006 15:13:34 -0800 Weatherlawyer wrote :
Floor screeds are about an inch thick. Why not run it an inch to 2
inches at the back so that any water flows straight out?

Make it about six to one very coarse sand and cement. Wet the floor
and lay it on tilt fillets or raised batons. When you finish a
section remove the fillet and fill in the space.

IME the usual spec for screed is 1:3, 50mm thick. I doubt whether 1:6
with a car being driven over it would last.

It would last..about 15 minutes!

Harry Bloomfield wrote:
Just a possible future project at the moment...

I'm considering both improving the flatness and increasing the floor
level of my garage by screeding it. It is a little uneven due to the
fact that I very slightly underestimated the quantity of concrete
needed, when I originally laid it many years ago - which left it a
little rough finished at one end.

It could also do with the original floor level to be increased by
about 1/2", to improve its resistance to flooding. The later due to a
clay sub soil holding water in extremely heavy periods of rainfall.
There was just a slight ingress a few weeks ago, which I would like to
resolve.

The floor area is 24' x 12'. I have seen screeding laid on top of
concrete to produce a good smooth finish, but how thin could this be
laid? How do you make a screed mix? Once dry, would it be waterproof
on might it allow moisture to track through it?

Any other ideas what to use instead? The finish will have to be fairly
rugged, able to cope with the weight of cars and their
maintenance/repairs.

Thanks for any replies.

Screed needs to be a minimum of about 40mm, anything less and it will
crack...the best thing for screed in a garage is granno (blue grit, very
coarse) mixed 3 parts to one part cement, although if you are putting it
thin, make it 1:1.

Prior to this you will need to make sure the floor is spotlessly clean and
apply neat unibond (PVA), screed while wet - you'd be wise to do it in
sections and have it sloping towards the door, where the granno feathers out
to nothing it's as rough as a bears arse, here you'll have to use
sand/cement mixed at 1.5 sand to 1 cement and again laid on wet pva.

Phil L wrote:
Harry Bloomfield wrote:
Just a possible future project at the moment...

I'm considering both improving the flatness and increasing the floor
level of my garage by screeding it. It is a little uneven due to the
fact that I very slightly underestimated the quantity of concrete
needed, when I originally laid it many years ago - which left it a
little rough finished at one end.

It could also do with the original floor level to be increased by
about 1/2", to improve its resistance to flooding. The later due to a
clay sub soil holding water in extremely heavy periods of rainfall.
There was just a slight ingress a few weeks ago, which I would like to
resolve.

The floor area is 24' x 12'. I have seen screeding laid on top of
concrete to produce a good smooth finish, but how thin could this be
laid? How do you make a screed mix? Once dry, would it be waterproof
on might it allow moisture to track through it?

Any other ideas what to use instead? The finish will have to be fairly
rugged, able to cope with the weight of cars and their
maintenance/repairs.

Thanks for any replies.

Screed needs to be a minimum of about 40mm, anything less and it will
crack...

The proprietary brands of flooring screed can all be used in much
thinner layers. Certainly the latex type can be feathered down to
virtually nothing without cracking


the best thing for screed in a garage is granno (blue grit, very
coarse) mixed 3 parts to one part cement, although if you are putting it
thin, make it 1:1.

Prior to this you will need to make sure the floor is spotlessly clean and
apply neat unibond (PVA), screed while wet - you'd be wise to do it in
sections and have it sloping towards the door, where the granno feathers out
to nothing it's as rough as a bears arse, here you'll have to use
sand/cement mixed at 1.5 sand to 1 cement and again laid on wet pva.

Stuart Noble wrote:
Phil L wrote:
Harry Bloomfield wrote:
Just a possible future project at the moment...

I'm considering both improving the flatness and increasing the floor
level of my garage by screeding it. It is a little uneven due to the
fact that I very slightly underestimated the quantity of concrete
needed, when I originally laid it many years ago - which left it a
little rough finished at one end.

It could also do with the original floor level to be increased by
about 1/2", to improve its resistance to flooding. The later due to
a clay sub soil holding water in extremely heavy periods of
rainfall. There was just a slight ingress a few weeks ago, which I
would like to resolve.

The floor area is 24' x 12'. I have seen screeding laid on top of
concrete to produce a good smooth finish, but how thin could this be
laid? How do you make a screed mix? Once dry, would it be waterproof
on might it allow moisture to track through it?

Any other ideas what to use instead? The finish will have to be
fairly rugged, able to cope with the weight of cars and their
maintenance/repairs.

Thanks for any replies.

Screed needs to be a minimum of about 40mm, anything less and it will
crack...

The proprietary brands of flooring screed can all be used in much
thinner layers. Certainly the latex type can be feathered down to
virtually nothing without cracking


They aren't screeds as such, they are levelling compounds, and you've hit
the nail on the head as to why they don't crack, they're flexible with the
latex in 'em.
As an aside, the term 'levelling compound' is a misnomer, they don't level
any easier than anything else, they smooth out easier but it's not
neccesarilly level.