Seal the concrete if you’re worried about it. I’d be more concerned about water damage to the bottom plate of your partition walls than I would with the concrete.

They make epoxy coatings for just such a use. Some businesses do only this for customers.

Lots of concrete doesn't have a coating however. Think about driveways, sidewalks, parking lots, street etc.

If you want your floor to be perfect then a coating is the way to go. Otherwise, it's probably fine.

Another commenter mentioned about the concrete and framing members around this space, so I'll leave that alone, but you seem unconcerned about the exhaust fumes. You shouldn't be. This room needs to have a continuous, undamaged vapour barrier isolating it from the rest of the house to keep you safe.

Thank you for this! I will definitely be looking into this. Don't get me wrong - I very much care about exhaust fumes.

Understood. Thank you for the tip!

Great point about outside unfinished concrete! Thanks for the input.

Heya, former WA peep here! If you're in one of the older houses with that setup (esp in the Kitsap area), highly highly recommend having a plan in case that basement floods, even a few inches.

I lived out in the Kitsap area for a hot minute, and every major rain storm trickled into our basement one way or another, so check your basement out during and after storms from time to time.

If you have a neighbor you're cool with who has a similar house layout, ask them if it's ever been an issue where you're at.

Winter in Washington, not a problem to park a wet car inside. The humidity indoors is lower than you might guess, thanks to the difference in temperature. Things will dry out just fine. The concrete will be undamaged; it will not be subject to freezing or anything. The portion of your garage that is below grade will be the cause of all your water troubles; a few drops on your car will be nothing.

You are going to hurt anything. However, I would make sure your "garage" meets code for insurance. They require a fire wall between any space with a roll up door. Or, you can have a garage door into your basement.
Not a huge deal but in the event of a fire, the claim could get complicated

>My concern is when the car is wet from rain and parking it inside on the raw concrete, which seems to absorb water.

A large absorbent 'oil change' mat in your parking space would solve this problem.

I also strongly recommend that (if your home isn't already required to have them) you consider adding carbon monoxide detectors to rooms that are connected to your garage space (like via a door, vent, ect.).

Got it. Thank you so much. The previous owner did have the outside waterproofed down to the foundation, so I'm not as concerned about that. But thank you for the input on the interior water dripping from the car.

Thank you for your reply! So, to be sure I understand - when you say "They require a fire wall between any space with a roll up door. Or, you can have a garage door into your basement." what do you mean? The garage door of the house goes straight from the outside into the basement, although there is a wood frame with drywall separating the garage from the basement. I still kind of think of the garage as part of the basement despite the basic wall.

Hey! Yeah, the previous owner did waterproof the basement by excavating down to the foundation on the outside and putting in french drains and such. Still, I make the rounds after every little rain (that's a lot of shoe leather!) and make sure the sump pump is working, too.

Oh, required or not, we have CO detectors in the stairway to the main floor and in the hallway between both bedrooms. I don't take that lightly. Before starting to work from the former workshop off the basement I also did a radon test, which thankfully came back very negative.

A sheetrock wall can be a fire barrier if it's made properly. But you want to verify that it functions as such, both for insurance but also because you don't want to kill yourself/family.

At least 1/2in drywall with filled cracks all mudded and gaps filled. Foam or firecaulk applied where any plumbing or wires pass through the drywall.

Doors must be solid (20min fire rated)

All havc duct must be metal.

Edit: passage door from garage to the reast of the house should be 20 fire rated, and typically you want self closing hinges. (The hinges code has come and gone and come back again last i saw. It keeps out car fumes.)

Thank you!

Thanks!

> A large absorbent 'oil change' mat in your parking space would solve this problem.

It won't magic the water away. Exactly the same amount of water will end up in the space whether the mat is there or not.

Another thought to look at would be any interior door between the house and basement/garage area being a fire rated door. We had to change out the door from our garage and house to a fire rated model to meet code

You have concerts drive ways . Foundations and roads that are raw and exposed to rain snow and salt ………….

Code requires the bottom plate to be PT, so assuming it was done right and those walls weren’t built super long ago, it should be fine.

Garage ceilings require 2 layers of 5/8" if there is a living space above.

Not a bad idea, but not required from what i have seen in my state (idaho has lower standards generally, so im not surprised.)

I have never seen double layers of drywall.

I used double layers on my HVAC air handler closet along with an insulated steel door for noise abatement, and doubled the sheetrock on the bathroom walls as well for the same reason, along with insulating both sets of interior walls. Very quiet now, it was worth it.

I do this for a living in the greater Seattle area, even a polished or just generally sealed concrete will go miles to improving the longevity of your concrete. At the very least, get yourself a product called lumiseal fx, 200 bucks for 5 gallons, and apply two coats after cleaning and scrubbing the floor. Will repel water and oil and any other contaminants your tires may pickup. Epoxy coatings are on the more expensive end. What I mentioned takes max 3 hours to do and apply, and can drive on it next day

Wait until you hear what concrete goes through when it's outside, like a road, driveway, culvert, wall, building etc etc. It's fine.

Wait until you hear what concrete goes through when it's outside, like a road, driveway, culvert, wall, building etc etc. It's fine.

I would cover the concrete with a water barrier

It says “…built in the 1930s…” so I expect code was different then.

It also says the walls are drywall, which was around, but not widely used at all in the 1930’s.

Carve a drain along the edge so water has a way to escape.

Get a standing squegy so you can push the water out.

That's awesome. Thanks very much for the tip!!