spray concrete curing compound for floor slabs? 1

[MikeE55]

I noticed that MasterSpec doesn't allow a spray cure compound for floor slabs to receive a floor covering, i.e. a form of wet cure is required. I know that dissipating spray curing compounds sometimes do not dissipate if they are not exposed to light and foot traffic, but they still seem to be the most common method of curing. Am I wrong about that? I would like to hear what you guys are specifying.

 

[AskTooMuch]

I cannot confirm if it was curing compound, but one big slab we poured on a hot day got lots of cracks and some top portion of slab are peeling off. I'd stay away from it if I can and require a wet burlap or ponding if specially big area pour and summer. In small area, I guess it's ok.

 

[STrctPono]

Sinak Lithium Cure 1000 or 2000 is the only curing compound that I know of that is not a film forming product. I.E. it will not affect the application of architectural flooring after as the film forming curing compounds do. We specify it for curing of every single bridge deck.

 

[dik]

Thanks for the info... downloaded the data sheets, and it appears to be a good product... will look into it further. apparently equivalent to a 28 day wet cure.

Dik

 

[bobby83]

In my area wet curing is mandatory for slabs. Curing compounds will never be equivalent in terms of shrinkage control(in addition to the flooring issue)

 

[Ron]

In theory, curing compounds can work. In practice, not so much. First, there is almost never a uniform coating of the material. It is haphazardly sprayed across the surface. Next, it has no ability to withstand foot traffic and the construction activities that will follow the slab placement in short order. Next, it does not provide an adequate barrier to vapor migration, thus does not keep all of the moisture in the slab. If you want to see that firsthand, tape a piece of clear plastic onto the floor slab after the curing compound has dried. Come back the next day and see if you have condensation under the plastic. Likely you will. If the material is "wax" based or acrylic based, it will prevent proper adhesion of overlying floor treatments. Cyanoacrylates are better but much more expensive.

There really is not a good substitute for proper moist curing. It doesn't have to be done for 28 days to be effective...even a few days makes a difference, preferably 7 days.

 

[dik]

Take a gander at the product literature for Sinak Lithium Cure 1000 or 2000.

Dik

 

[MikeE55]

The Sinak products look impressive, but they do not seem to be for interior slabs that will receive a floor finish. I know that wet curing is really the best way to go, but still wondering if that is the most commonly specified method for interior slabs. Most of the General Contractors in my area say it is not, but it is obviously their preference to spray the curing compound, whether it is working well or not.