Slabs laid using builders sand?

[55palfers]

We've just had a fair bit of work done in the garden including laying a load of slabs.

I was always told (by trusted artisans) to use sharp sand for slabbing?

What do the PH landscape collective reckon please?

Thanks
PS anyone know a good slabber in the Solihull area?

[Muncher]

http://www.pavingexpert.com/layflag3.htm

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.

[55palfers]

Thanks for that Muncher.

The complete tosser we have just had the misfortune to employ has used builders sand and laid them in entirely the wrong pattern!

We've had some new Indian sandstone flags laid in another area and he has assured me that those weren't laid on traditional blobs but some grey looking grouty sort of stuff??

Basically I want to take 80% of what he's done (using loads of old weathered concrete slabs we had already) up and get it re-laid the way I initially asked him to do it. He's not keen.

Why don't people listen?

[Muncher]

You really shouldn't lay them on blobs either...

[shtu]

55palfers said:

traditional blobs

Why don't people listen?

Because he might not be as clueless as you think.

Have a read up on the excellent pavingexpert site about the "traditional" method you mention.

As for the pattern, a photo would help see if what he's done is any good, there may be a very good reason he's not done it the way you asked. Or he could be hopeless, hard to tell yet.

[TA14]

shtu said:

Or he could be hopeless, hard to tell yet.

generally speaking using building sand to lay slabs = not good

[KAgantua]

Just curiously

Understand Building sand is a no no for laying slabs on a sand base, however if you are laying on compacted hardcore/ MOT1 then full bed of mortar, it is acceptable to use building sand then, right?

[55palfers]

Basically, I have a large area at the top of the garden that used to be my veg plots.

Due to having heart failure my digging days are over so I want a low maintenece area.

I have a lot of old weathered slabs but not enough to butt them up over the entire area.

However, if you lay them with about a ten in border to each slab, infill with gravel - hey presto area covered and it will look OK

The guy didn't follow my instruction about a border all round each slab. Then he went out and got some crappy concrete ones to fill in the gap by the fence.

I have just had then taken up!

Had they been spaced as I wanted there would have been plenty. he didn't even put a few slabs by the shed door to get the mower out on to, just the gravel.

What he's done isn't too bad, just not what I wanted him to do.

[Alucidnation]

A lot of paving i see being laid now has a concrete base poured.

Slabs then laid on top with normal sand and cement.

One of my clients had his done this way about 5/6 years ago and it is still solid with no grout coming out or loose slabs, and thats in a garden that is occasionally submerged under an inch of water with heavy rain.

[shtu]

Yeah, that is a bit pants.

Tricky to even suggest a "good" way to lay those, on a full bed you're going to get debris and ponding in the gravel bits eventually.

However, what about just setting out an edge where they run out and leaving that side gravel-only?