I am planning to paint a concrete basement shop floor with epoxy, and want to be sure I am preparing it properly.
There are bumps that need to be scraped.
There are cracks that probably need to be chiseled open, then filled.
There are 1/4″ expansion joints that would seem to want some kind of filler, perhaps flexible.
The floor is dirty, but only a few years old. It was used by the painters as their paint shop, so not virgin concrete.
What should I used to patch and fill? What other prep?
Replies
Greetings Genoa, As a first time poster Welcome to Breaktime.
One thing is to make sure there is no moisture coming up through the pad.
I've recently seen an epoxy system loosen and bubble up from moisture gathering beneath it.
Parolee # 53804
Thanks, the slab has been in place for 3 years in a very dry climate with no groundwater issues, and has been (and will be) heated with in-floor hydronic heat during that time.I am worried that the paint overspray and spills on the floor will resist good adhesion, and after 2+ years, it will not be easy or practical to remove.
There should be some experienced posters along shortly.
Cheers
Parolee # 53804
http://www.concretenetwork.com
http://www.miracote.com
Within these, search for concrete prepartion.
There are several possible issues, most of which are probably detailed in the product info/instructions on the paint you're going to use. I was on a job last summer where they were refitting a shop for another use, with an epoxy paint. With this product, there could be no sealer on the concrete, nor any grease. They recommended bead-blasting it and also the owners wound up using a rotary floor grinder to take out the high spots.
We used to acid wash concrete before applying epoxy but now we have much better success with shotblasting the surface first. It is absolutely crucial that you have an absolutely clean, solid base to have the epoxy adhere and provide protection for decades to come.
Concrete with a soft layer that is subject to dusting will never make a great base. You have to remove that soft layer.
Gabe
sorry to hijack this thread but 1 qick question. How long does one have to wait after its poured to apply epoxy? is a few years like op the way to go?
Age is not as important as moisture content. Each manufacturer has his own specifications.
Areas that are to be epoxied should have a VB if there is any concerns regarding moisture wicking up under the epoxy. We don't always use a VB if it's on a dry base.
Basements are the worse to epoxy if they were finished with a power trowel.
Gabe