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resurfacing a porch

I want to put a new, sanded concrete surface over an existing, roughly painted, concrete surface. Is it possible to do this without first removing the old paint?

Re: resurfacing a porch

do you mean "sanded" as in smooth or polished concrete surface, or "sanded" as in a textured surface which has sand mixed into the paint

Re: resurfacing a porch

I think it's possible to do what you want, you just need to use a concrete bonding agent on the old paint.

Basically, the difference between a gallon jug of concrete bonding agent and a gallon jug of white wood glue is time.

With white wood glue, the glue will always re-emulsify if it gets wet and stays wet for a long time; even if it's been dry for decades.

With concrete bonding agent, you have a time window in which to place the new concrete over the old. The moisture of the new concrete reactivates the concrete bonding agent into glue, and that concrete bonding agent then bonds the new concrete to the old surface. But, you have to place the new concrete within that time window, because after that time window expires, a chemical reaction takes place in the concrete bonding agent that renders it unaffected by moisture forever after.

Since new cement won't stick to existing concrete, contractors use concrete bonding agents to bond new concrete to old concrete, even in underground applications where it's expected that the glue will be exposed to moisture for extended periods of time.

Re: resurfacing a porch


Check out this website for a product called "Restore": WWW.SYNTA.COM. This is an acrylic based, sanded coating, intended for restoring long in the tooth wooden decks, but is also suitable for concrete. If your existing painted concrete is tight, you shouldn't have a problem going over it. Naturally, the adhesion of the new material is only as good as the adhesion of the material under it.

Restore can close up quarter inch cracks in decks or concrete. It has been selling like hotcakes at Home Depot. It requires two coats and the result is a 40mil finish coat, about 10 times a normal paint finish. It is applied with a looped plastic roller which distributes the sand in the acrylic.

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