FAQs Floors

Gypsum Concretes

Is gypsum concrete strong enough?
There are gypsum concrete toppings that are 4500 PSI and above which is higher than most slabs.

What are the advantages of gypsum concretes?
The advantages of gypsum concretes are they offer extremely flat floors, minimal cracking, and fast set times. These are characteristics not found in other underlayments.

What is the minimum thickness you can pour?
The minimum thickness you can pour over plywood/osb board is 5/8" thick, and over concrete is 3/8" thick.

How many square feet can you pour in a day?
At 3/4" you can pour +/- 20,000 square feet in a day.

When can I put floor covering on?
According to the guidelines, you can put the floor covering on in +/- seven days. But the true test is to do a moisture test, either a delmhurst or a rubber mat test.

How can you pour gypsum concrete over metal deck?
Pouring gypsum concrete over metal deck is a two step process. Slurry the flutes (fill to the top of the metal deck), let that take its initial set and then pour your top coat at a minimum of one inch above the metal deck. You can also put soundmat between your first coat (slurry) and the top coat for sound control.

Cement Based Underlayments

What are the advantages of a cement based underlayment?
The advantages of cement based underlayments are that they are cement based and not gypsum based. They typically have a higher compressive strength, and they are fast setting, fast drying, and self leveling products.

Do you have to bead/shot blast the floor?
In most cases, yes, you do need to open up the floor to get a good adhesion to the concrete substrate, but not always. With certain cement based underlayments like Level-Rite, you don't have to.

How fast can you set tile?
You can set a breathable tile in four hours.

What is the minimum thickness you can pour?
You can feather edge at high spots or door ways and pour 1/8" minimum over concrete.