painting/sealing indoor plywood floor

Hello all,

In my soon-to-be house there is bare plywood flooring. I can't remember if the wood has been treated with wax or coating of some sort. I would like to paint and seal the wood and leave it at that.

I have been told that I will have to either use a 'porch and floor paint' in my desired color (because apparently it's a two-in-one colored primer...is that right?) Then seal with water based polyurethane OR buy oil-base primer and paint and seal with polyurethane.

Obviously, I have no experience with this and no knowledge as to what will hold up the best or what will expose minimal toxic gick

which makes me wonder, does anyone have suggestions for less toxic alternatives to get this done? any tips/pointers you think may be helpful for me will be so appreciated

There are plenty of latex finishes that have a decent shine.

I'm on a painting job today. I'll post some photos later.

Will that alone do the job to seal the wood? And will I have to prime the plywood before applying the latex finish?

Primer is generally cheaper than your actual paint.
By putting on a coat of primer you use less if your actual paint. The primer soaks into the wood and fills a lot of voids that you would other wise waste more expensive paint in. Plus the primer gives a better bonding surface than the actual wood.

My suggestion would be to clean and sand the floor before any paint. Clean the floor a few more times. Roll on a coat of primer. Let it dry. Come back later that day and with a pole sander knock off any burrs that were in your paint when it dried. Go back over it with a sanding sponge and your bare hand to check for any rough spots. Clean the floor again. Apply another coat of primer. Let dry. Knock off any burrs again. Clean the floor once more. Then apply the final coat of your actual paint. It should cover in one coat.

But I'm a stickler when it comes to painting.

Minka, I've added your thread to the 'finishes' forum. Here is one thread from that forum that discusses natural floor finishes a bit...
https://permies.com/t/43967/toxin-ectomy/painting-sealing-indoor-plywood-floor#346903 . In the end we left our pine floor with no finish and it is mellowing nicely.
Are you wanting a floor finish to waterproof the plywood? Or to seal in its toxicity? I wonder if something totally natural as mentioned in my thread would work for you?

Thanks for all the insight!

I was looking to 'seal' the wood to make it more waterproof...4 dogs and a toddler = lots of wet messes!

So, after priming, then painting, should I add a layer of something to 'seal' it? I was told to use water-based (don't know if that's important) polyurethane for the final coat on top of the paint for that reason...but is this necessary?

Hau, Minka bug, Is this a floor that you want to leave the natural wood look or do you want to add color to the floor (paint or stain)? How long can you wait for the finish to dry before putting it into use? How much money are you willing to spend for floor finishing? These are things I consider when putting any finish on anything.

Painting will take around 3-4 days, maybe even longer if the humidity is high. Then there is the option of drying oils, such as linseed and tung oil. The Penofin company makes a line of suitable products Penofin company You might find exactly what you desire in their product line. Then there is the Minwax company line of polyurethane finishes, which are fast drying.

I like the idea of linseed oil if the plywood has a nice quality veneer but I think shellac might be sturdier. It's been in use for thousands of years and is actually edible!

Hi Minka,
I have plywood floors in a portion of my home that I installed about a decade ago. They have aged well even with 4 large inside dogs and one youngster. I used Osmo polyx oil, but it's expensive and not as natural as I would like, so I would recommmend a drying oil like linseed with shellac on that and a coating of wax that gets re-polished every few years.

I am attaching a few pictures of the floors and a cafe remodel that I used BLO and shellac with a light wax polish. I can walk you through the application process and you will be soooooo much happier than with latex paint.

I'll get the other photo later

Bill, it looks like you stastarted with a very good grade of plywood. Both jobs look great. I look forward to the step by step.

I highly recommend looking at pure tung oil (not the stuff called tung oil at the store).

I used this for 5 rooms of hardwood floor, and I am very satisfied. I did have to use mineral spirits b/c I did not have the budget for the citrus solvent.

I tried this with the regular tung and then the darker stain tung from the site below.

I don't think this would work with painted floors. I think I used an 80 or 100 sand as the final b/c we were in a hurry to move into the house. I also did roughly 3 or 4 coats. I wish I would have done a couple more, but I was pushing for time.

If you have any type of floor that has any type of wood beauty to it, then I would check this out.

http://www.realmilkpaint.com/oil.html

I was looking into similar needs to stain/paint our deck. We're a little concerned about chemicals in most paints/stains and our neighbor has a coy fish pond so I'm pretty careful about what I do in my yard so as not to kill her fish. Apparently the previous owner would stain the fence every couple years and wipe out her fish. Whatta jerk!

I'm not sure where I found this at, maybe it was here. Either way maybe it will help you in your search.

http://www.earthpaint.net/

I just want to mention that when using linseed oil, even the pure stuff, un adulterated with solvents and what have you, the off gassing from it is significant and takes quite some time. It will be unfortunate if you end up living in an enclosed place where the linseed oil is drying.


I had a couple of gallons of flax oil (same stuff) that I put on an experimental cob floor in the garage. It is a great surface, water repellant unless you leave great pools of water for long times, like several days (my daughter using a "wet saw" for tile work), tough, pretty, withstands abrasion and so on, but it reeked for months.

Plan for it, and you'll be fine.

Thekla

This may not be quite what your looking for, but I ran across some information recently about using borates to preserve wood. Here is an article from the old house journal describing it.

Basically Borates are toxic to the things that love to eat wood, but is nontoxic to humans (for the most part). May not be so necessary inside. but I would love to not use any paint outside and use this stuff. I would love to be able to see the bare wood, but still know that it is well preserved.