Have you ever considered using osb as a finished floor option? Yes, I know that it is rough construction product that doesn’t look so very pretty in it’s pre-finished state! But, this board is strong and durable and the unique makeup of the strands creates a surprisingly nice design that really pops when finished.
When we built our cabin, we were looking for inexpensive options for….well everything! The walls were taken care of with whitewashed plywood and we made our own concrete sink for one of the bathrooms. We thought the flooring should be just as unique.
We didn’t know of anyone who had finished the rough osb flooring before but we thought…why not? If you have a vision, you might as well go for it! The worse that could have happened is that we would have had to cover the whole thing up with flooring in the end but we figured it was worth the risk.
It does take a bit of elbow grease so we were hoping beyond hope that our little plan would work!
How To Finish OSB
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Materials And Tools Needed
- floor belt sander – we rented ours
- varathane floor finish
- painters pad
- long handle extension for painters pad
Finished OSB Flooring Instructions
First we had to sand off the green lines that came painted on the sheets of osb. I really think they should just leave those silly lines off the wood to begin with but what is one to do! We rented a floor belt sander for a day and made quick work of eliminating….most..of the lines. There are a couple of faded areas in inconspicuous spots that we just left for character lines..haha.
Once we finished sanding, we had to vacuum and sweep up all that dust! Now the hardest part was over.
We used Varathane floor finish to protect the floors. Using a painters pad with a long handle extension, we applied three very thick coats. I mean VERY thick coats like puddles almost. The osb will soak it up pretty good….especially the first coat. It takes a while to dry between coats. We ended up applying one coat at a time between the weekends that we were up working on the cabin. As we left, each of the weekends, we applied a coat and went on our way. So…I am not really sure how long it takes to dry.
I am very happy with the end result! The floor is hard, smooth and shiny. It holds up very well to all kinds of traffic too. I would definitely do this again.
Finishing the sub floor was just one of the cost effective projects we had done at the cabin and it’s probably our favorite. For a fun wall accent, we also put up thin brick veneer.
oil or water based and what about holes from screws and gaps between boards. Did you use a filler?
We used oil based for this floor which worked very well. It takes longer to dry than water based but I think it’s a little more durable. Just recently we did another floor above our garage using water based. It dries much quicker and doesn’t have an odor but I think I need to add some additional coats to get a more durable coverage. For the gaps, we swept the sawdust, from sanding the floor, into the cracks. This worked perfectly for filling gaps!
How do you think the varathane will fare on uneven floors, especially with the thick layers? We like to joke that there are no “square feet” in our house. Thanks for the idea!
There are several Varathane for floor finishes. Which one did you use? Label color might help.
We used the glossy finish. It was also labeled for high traffic.
Did you stain your floor after sanding it or leave it unstained? We are just about to do this in our garage remodel. How is the floor holding up after a few years of use?
We left the floor unstained and it got the richer color just for the floor varathane. The floor is holding up great. In fact, we are about to repeat this process in our garage loft.
I have finished osb board floor with glossy varathane Pro but there is lots of little dips or holes where it seems like the varathane just seeps away. Can u tell me what I can do with these? I have applied 5 coats.
Can you apply the Varathane Floor Finish using a squeegee….pour it on and drag it towards you? As opposed to using a roller or brush? Seems that would be an easier way to get it on thick. I am getting ready to experiment with this in a spare bedroom and just looking for the easiest “fool proof” way to do it.
Very nice. I see this has been in for a couple years now. I have been looking at doing the same thing and am curious as to how yours has held up for durability?
I just did a similar application. I ripped the 4×8 sheets in half and left me with 2×8 sheets. I ran them through a drum sander. it took about an 8th inch off, and smoothed out a lot of the flaky chips and gave it a much more “cork” look. I was leery of the natural yellownish of the OSB so I made a light combination of a pickling white w/ a small amount of gray. This took down the yellow and gave it a lighter almost grayish tone. I did a tiny 45degree bevel on the edges with an 80 grit orbital sander. This will make a small gap for more eveness when sheets are butted up against each other. I did 2 coats of Varithane Diamond Floor finish rolled on heavy and back brushed to knock down the bubbles, then a sand with 220 or large fine sanding sponges, and repeated that same process again. you can slide in your socks across it. (this was before we put it down) the plan is to put it down, screw it off with a nice handsome, industrial looking counter sunk screw and apply one more very heavy coat of Varithane to fill in the edges and screw heads a little.
It was a lot of work but the Varithane sets up in about an hour and were able to put two coats in the same day. Hand sanding 30 2×8 sheets of clear coated OSB twice, was about the worst of it.
Rick, I would love to see the finished product!
Wow! That sounds like quite a process. I would love to see a picture 🙂
How did you handle the seams?
My husband and I are trying to go the cheapest way to make a livingroom floor cant afford to put down hardwood floors we bought sob borads
can you varnish them and go over with some kind of gloss
OSB WILL soak up water and never dry out, so lots of sealing needed, esp. in kitchens, or at doorways with water/snowmelt.
That said you can do something similar with plywood, stain, adding thin router lines for a plank look. There is a great little book by Jocasta Innes
“Underfoot around the house”…great ply/cheap ideas that can also be used on OSB too I think.
In CA real estate home sale you can simply PAINT any flooring-ply/etc to be considered a ‘floor covering’ for loan purposes.
I love the look of this… Have been struggling with what to do with our current carpeted floors without busting budget, and this offered a terrific option! Quite clever.
I love the look of these, almost similar to a cork flooring we put in a closet. I was wondering if you could tell me if you used a vapor barrier or retarder between your sub floor and your OSB finished flooring?
The sub floor was the finished floor (one and the same). We simply applied the Varathane floor finish to the OSB sub floor.
Water-based or oil-based Varathane? There’s both kinds.
I’m using Polyurethane on my OSB floor but when I started the 2nd coat, bubbles started to show everywhere. Did you have the bubbles by chance and if so did you sand after each coat or at the end? Thanks and all help is greatly appreciated.
We did not have any bubbles. Are you using Varathane floor finish or regular Polyurethane. We used the Varathane and applied it quite thick.
Hi. I am getting ready to do this in my home. I can not take the carpet and my budget can not afford a new floor right now. My question is. Did you stain? And in between coats of the sealer did u have to sand?? Or just sand before ? Thanks so much. This looks great. Hoping mine come out as good.
Nice work. I just did my office at home with 2X2 squares of OSB. I used deck screws and counter sunk them then coated the sanded floor with polyurethane. I cut cheap plywood into strips for baseboard (polied as well). It was a lot of work, but I love it. My wife however doesn’t like it and won’t let me finish our boys room with it…bummer. I’m wondering if you’ve tried anything else since this project? I’m thinking about painting the tiles in two different colours to make a checker board pattern with just a bit of the wood texture left behind for character. Any thoughts?
We love the warm and unique look of your floors! I plan to pin this project to our Flooring pinboard. Check it out at pinterest.com/homedepot
Thank you! I will look forward to seeing that!
What kind of Varathane did you use? How many gallons did it take to do your space?
We used Varathane for floors in a glossy finish and it took about six gallons for approximately 720 square feet. We applied each coat VERY thick.
Thanks for the great information! We’re looking to give our house a rustic look and I think this is a great option!
Unfortunately, when our house was built the contractor nailed the floors while missing all the floor joists; so my husband and I are trying to figure out the easiest and most frugal way to fix them ( not rip out laminate,etc.) I’ll send pictures when we’ve done the floors!
Oh no! – I’m guessing you have some pretty squeaky floors. I would love to see your pictures when your are done!