patio slab question

Old 05-16-07, 12:30 PM
Thread Starter
Join Date: Apr 2006
Posts: 36
Upvotes: 0
Received 0 Upvotes on 0 Posts
patio slab question

We want to put in a bluestone 'patio' at the side of the house we're renovating. It is a relatively small area (approx. 10' x 10'), half with a roof over it and half exposed. Right now there is cement in poor shape under the roofed area and half of the exposed area- it forms a kind of 'L'- we'll be turning it into a square. The existing cement looks like it is about 6+ inches deep (maybe quite a bit more, but I haven't dug around it yet to see. The surface is in bad shape, but there don't seem to be any major cracks through it. I'm wondering if we can just remove the loose stuff and pour a couple fresh inches of cement on top of what is there, then put a layer of sand or rock dust to lay the bluestone in. Raising the overall level isn't a problem (up to maybe 5-6"). But would we be better off breaking up and removing the existing cement and starting over?
Old 05-22-07, 03:49 PM
Join Date: Mar 2007
Location: central nj
Posts: 24
Upvotes: 0
Received 0 Upvotes on 0 Posts
patio slab blues

I've laid pavers ontop of concrete walkways and even porches but only if the concrete was solid, undisturb by any flaws-But that is with pavers where we actually glued the edges into place
- I've extended existing concrete patios with roadstone/quarrystone {fines mixed in w/3/4} pacted/tamped properly, laid sand and then and added all new pavers over entire patio.
-There are adhesives you can apply to cleaned older concrete and apply new concrete ontop (most say at least 2")
-It is possible to do what you are asking but a lot of work and in the long-end, if it doesn't work, than you'll have a unsafe patio with cracks and blue stone lifting maybe? but this is cheapest, the least work/labor intensive way to go.
I would suggest to just remove the loose stuff, box in the very far edges where the patio will extend to (w/pt wood) and raise the entire level (even new edges) with clean 3/4 blue-stone and compacted roadstone on the dirt area, level/pitch properly, sand/pea gravel/stone dust and drop your larger bluestone or slate ontop. be careful with the bluestone/slate-the thinner it is, the easier it cracks while trying to level it-
(try to keep the cracks or joints close together, less likely to move)
-whatever you do, just be sure existing slab runs away from house for proper drainage before--if it doesn't pitch properly, might as well tear it up and start fresh-good luck

Thread Tools
Search this Thread
Ask a Question
Question Title: