Laying Indian Sandstone on a concrete slab.

[Mister Dobbo]

Hello, I'm going to be laying a 35m2 patio on a concrete slab, the slab was a workshop and is reinforced, solid with no cracks. I was going to lay the slabs with a slight incline for drainage.

The mix I was going to lay them on is lean mix mortar (10 grit sand - 1 cement) semi-dry starting at 2.5" down to 1/2".

Any comments on if this seems right please?

Thanks.

 

[WabbitPoo]

Too dry, and too gritty. More sand, more water. Search for more details.

Have fun

 

[Mister Dobbo]

Too dry, and too gritty. More sand, more water.

Hmm, one site said the 10:1 ratio as it only need to bind the grit sand, others say 5:1. I'll go 6:1 semi-dry!

I was looking at this site:

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

 

[WabbitPoo]

Your choice. Have fun. You'll find it easier with a wet mix. I dont find they bond very well to sharp sand and cement, especially with a damp mix.

 

[Mister Dobbo]

Gone with the wet mix as advised and all going well

With the pointing I was going to use 3:1 soft sand & cement fairly dry so I don't stain the paving, should I sprinkle with a bit of water when it's pointed up to help it cure? The paving mortar will have dried as I'll do all the pointing at the end.

 

[r896neo]

I use plastering sand as it stain less and i find the mix of courser sand and soft sand gives a harder joint. No need to sprinkle with water unless its very hot in which case a tiny sprinkle after 2 hours after finished and then every 2 hours for the rest of that day. Alternatively cover to keep the sun off it.

 

[Mister Dobbo]

Thanks r896neo, I cant see the sun being a problem so I don't think I'll need to wet it then!