ack! moisture in the concrete after rain

[mktbully]

so got a little rain up here in the NE and i notice that a corner of the garage is slightly darker than the rest of the floor. i don't see actual water pooling or anything but the area looks to be a little damp so is this a no go for epoxy coating for the floor?

the grade of the rear of the garage seems to be pitched towards the garage so that might have something to do with it but i won't get to repair that until much later.

 

[thegarageguy]

All is not lost. You may have to just waterproof it if you want an epoxy system. Without looking or testing we'd never know though.

Your other alternative would be an interlocking tile.

 

[Shocker]

Holy cow! I have the same issue. Back 2 corners of my new shop has the same issue. Just slightly damp to the touch after a good rain.

I have been waiting to see what I can do later this year. I figure it is coming through the stem wall a bit. I am thinking I can seal the outside of the slab and see what happens. Otherwise it will be interlocking tile.

 

[mktbully]

All is not lost. You may have to just waterproof it if you want an epoxy system. Without looking or testing we'd never know though.

Your other alternative would be an interlocking tile.

I want to avoid the tiles if i can.

i understand you have to look at it and do tests before you can comments...but GENERALLY what is done to actually waterproof it? is it a coating that is applied before the epoxy or is it something more drastic like seal the foundation, dry well, etc?

 

[thegarageguy]

A waterproof membrane or vapor emission blocking epoxy. Its used as a primer. Most expert installers should have this formula available to them. I'm almost positive its not DIY.

 

[jkeyser14]

Wolverine coatings told me they didn't have anything a DIY'er could apply for garages with moisture coming up. I talked to two other epoxy companies that said theirs would be fine. One was epoxy-coat.com who said their epoxy is good with up to 12 psi of moisture pressure under the concrete. Another company which said they commonly use their epoxy on pool decks and other moisture rich environments were willing to guarantee their product, but the price was ~$3 per sq. foot for material (5-6 mils thick). I'm going to have my garage tested to see exactly what the pressure is.