Return to the Gardening with Stone Forum
| Post a Follow-Up
Flagstone on top of concrete?
| | |
Posted by Sue0661 6b, NJ (My Page) on Sun, May 1, 05 at 10:34
| Hi all - we have a 12 yr. old 24 x 28 ft. concrete patio that has cracked and looks terrible. My thoughts are to install flagstone on top of it. I know nothing about how to go about this, or where to start. Any suggestions?
Sue~ |
Follow-Up Postings:
RE: Flagstone on top of concrete?
| | |
| Flagstone, bluestone, and other 'slate' type stones are frequently installed on concrete slabs in many applications. Typically there's a mortar bed on top of the concrete into which the stones are set. Sometimes an asphalt base is installed on top of the concrete, and the mortar bed is installed on top of that. The difference between what you have and a new installation is the concrete base. A new concrete base has no cracks. Cracks in an exterior slab usually indicate movement of the slab in some manner. And on can never be certain that the cracked slab won't move in some way yet again. A new slab constructed for the specific purpose of being the base for a stone surface is usually reinforced, yours is probably not. Going to all the work of covering the cracked slab with mortar and stones, only to see it all crack if the slab moves again, which it may, would not make you happy. Although your slab is large, in the long run, it may make more sense to remove the slab and then install the stones on a new base and bed that would not necessarily have to be concrete. |
RE: Flagstone on top of concrete?
| | |
| Sue, can you send pics or define "bad". If it is just the surface cracking, then by all means do flagstone. If it is cracking and rising or sinking, don't waste your money on flagstone, but tear it up and do a new slab. Treebeard is right on in installation. I would suggest "flexible mortar". See your local hardware store. |
RE: Flagstone on top of concrete?
| | |
| We just did this, and it worked out fine so far. We also had a small crack in the old concrete, which I believe was due in part to ground shifting, but also due to a somewhat poor job in the first place. The flagstone installer basically built up and leveled the existing patio to be more level, plus we enlarged the patio. Keep in mind that you will also increase your height by 1.5-2 inches. |
|
|
|
|
