Paving Stones & Sand: Damp vs Dry?

[(PeteCresswell)]

In the few videos I've watched, they tamp/compact the gravel, but not the sand that is layed over the gravel.

In my test fit, I'm using about 2" of sand over solid shale. viz:

A local playground is being re-done and there are piles and piles of sand there for the taking.

Problem (?) is that it is damp and I do not know how that goes down paving-wise.

What I'm finding is that I can hand-tamp a 2" layer of the stuff down almost 1/4".

Don't have any dry sand to compare with, but I'm wondering if the tampability is due to the dampness, or is that just the way it is with all sand.

I'm thinking settling over the years...

Bottom Line: Am I asking for trouble if I chince out and use the free (damp) sand? Or should I pony up the cash and buy some dry stuff?

[Pat]

Normally 1/2" of sand is used. I don't think it matters whether it is damp or dry. If the sand layer is too thick it can pump and move under the pavers. If you need to use 2" of sand I would add some cement so it would set up solid. I think this is called thick set.

[krw]

The instructions I've seen all call for 2" of sand. I've also seen where one can add some concrete mix to it (unmixed) but it's always been 2", probably so one can get a good, level surface.

It should be compacted but I've found that wetting it and leaving it for a few days works. If it rains, all the better.

[Pat]

Here is a link to some directions that say no more 1 1/2"

is a paving stone manufacturer near my home and I have attended their seminar a couple of times. They say 1/2". I have used 1/2" on all my projects. I have watched a contractor use 2" of thick set under pavers on a project.

Here is a link to paving stone installation instructions that call for 1"

[Jim Elbrecht]

I've always tamped [machine tamped if possible] both the gravel layer and the sand [or, as I prefer, fines.

Wetting them helps the tamping process. After it is tamped to a point where it will compact no more- I spread a very thin layer [1/4"?] to bed the paver, which I pound into place with a 4-5lb dead-blow mallet.

If this sand was under a paver patio- and you know it was staying in place for years- then it might be sharp sand. If it was play-sand, then leave it. You want sharp sand under those pavers.

You should be able to tamp 2" down to about an inch- with a machine. You can bust your hump for 100 hours- and do it all over again in 2 years. . . or rent a machine- tamp *Sharp* sand down in an hour or two- and not have to touch it for a decade.

-snip-

I'd buy *sharp* sand-- and rent a tamper for a 1/2 day. All money well spent.

Jim