Hi all, great site you have here!!
Ok so I have an area that used to be used for parking, basically its 4� of compacted hardcore topped with about 3� of concrete, it’s been solid for around 10 years.
I’m now looking to slab over it, will this base be ok?
Planning on laying slabs on a bed of mortar on top of existing concrete, the finish on the concrete is quite smooth do I need to prep the concrete to ensure the new mortar will stick to it, thinking of keying it with stone disc or does it need some sort of bond/adhesive??
Many thanks in advance
Laying slabs on to concrete
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Tony McC
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Old concrete can have a microscopic layer of dirt on the surface that even power washing won;t shift, which is why we usually "etch" concrete with very strong hydrochloric acid before putting a new cementitious bed over it.
This may be seen as excessive for a patio, but if it's peace of mind you want, then that's the way to go. However, for me, simly priming the base with a coating of SBR or using a Slurry Primer Bond Bridge would be more than adequate.
This may be seen as excessive for a patio, but if it's peace of mind you want, then that's the way to go. However, for me, simly priming the base with a coating of SBR or using a Slurry Primer Bond Bridge would be more than adequate.
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