Sharp sand

[Wiggy9]

I'm aiming to lay my Indian Sandstone flags on a 10:1 dry mix. This will be going directly onto an existing concrete slab.

Although I specifically asked for sharp sand, what I have been supplied with is labelled as Plastering Sand.

Is this workable for the above situation?

[Bob_A]

According to the main site plastering sand is not suitable.

Unsuitable sands:
What is NOT suitable as a laying course material is any form of Building Sand. This is the sand used to make a bricklaying mortar, and it may be known by a range of other names: soft sand, masonry sand, plastering sand, pointing sand: any of these are NOT suitable.
And there are three key reasons why they are not suitable:

the grains tend to be rounded, so they roll around with each other instead of creating an interlock.
the small grain size enables them to hold a relatively high water content, making them ideal for mortars but bloody awful for laying courses.
they have a relatively high clay and silt content, which again makes them less free-draining than is required

Taken from here
http://www.google.com/custom?....ert.com

[lutonlagerlout]

sadly sharp sand has different meanings around the country

you need grit sand,flooring sand,screeding sand,riverwash sand

sharp sand as some lads up north call it is plastering or rendering sand down south

sorry but its no good
LLL

[Wiggy9]

Yes - I saw what the main site says about using building sand - but it is in the section on unbound sand.

I'm aiming to bind it with cement. Is it as critical if the bedding is bound?

[lutonlagerlout]

sorry m8 if its plastering sand its not strong enough,with or without cement
I know this because we had 20t of sharp delivered to a job and the polish screeders used it
of course it was plastering sand and the whole of the screed failed within 6 months
its a minefield ordering sharp sand ,better off saying "grit sand"
cheers LLL

[Wiggy9]

OK - I hear you. Thanks again for the advice and fast response.

[Wiggy9]

The supplier has agreed to take back the plastering sand.

However, he issued dire warnings about the danger of using paving or grit sand with Indian Sandstone.

He said that it would at some future stage cause the flags to pop up, due to a combination of the high water retention inherent in the coarse grain combined with freezing weather.

He said this didn't apply to other types of stone - just Indian.

What do you reckon lads?

[Bob_A]

The supplier has agreed to take back the plastering sand.

However, he issued dire warnings about the danger of using paving or grit sand with Indian Sandstone.

He said that it would at some future stage cause the flags to pop up, due to a combination of the high water retention inherent in the coarse grain combined with freezing weather.

He said this didn't apply to other types of stone - just Indian.

What do you reckon lads?

Sounds like bollox to me.
Go by what the main site says rather than your supplier.
Rather than admit he was wrong it sounds like he's trying to make excuses and justify what he supplied.

[ilovesettsonmondays]

your supplier has got his wires crossed .if you look at his statement sounds like hes talking about indian pilau rice :p