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Very detailed writeup about one of the projects that me (healthcare) and husband (electrician) have done on our 1901 foursquare mostly DIY. I include this painful level of detail for anyone inexperienced like me who wanted to know every single step people took to tackle projects.
When we moved in, there was old hardwood in the foyer, dining room, and living room. The DR/LR is Douglas Fir. The foyer looks like oak, which I've been advised is probably not original but maybe postwar. In the DR/LR, there were large areas where the finish was completely worn off, so we decided to go for a full sand and refinish.
The kitchen & little vestibule down to the basement had linoleum flooring probably 20-30 years old. We gutted the kitchen for the remodel, so I had full access to the floor in the room, and I decided to play the floor lottery. If I lost, the plan would have been to tile. I pried up the first layer of linoleum and a layer of subfloor, which revealed... more vinyl/linoleum - but with hardwood planks underneath! Win! This linoleum looked quite old and was adhered right to the dang hardwood underneath. We put on respirators and used an IR heat gun to warm the tiles up, and they peeled away nicely with a prybar.
After getting all the linoleum up, we found the kitchen hardwood floor looked in decent condition. But, the whole room was bordered in thick black adhesive on the wood. I assume this was black mastic adhesive, containing asbestos, so I didn't want to sand it off. I got on my PPE and got the adhesive wet, and then scraped it up using a painter's multitool and a sharper carbide scraper. It was gross, tiring, and time-consuming, but it worked. Took a couple days of work. I left most of the remaining adhesive under where the cabinets were going to be and decided we just wouldn't sand/finish those portions of the floor. Hope I don't regret that in the future.
There were also a zillion staples in the wood. Channel locks and regular pliers broke the staples, which was frustrating, but I got a pair of vice grip pliers which removed them perfectly.
After removing the adhesive, the floor looked ok - some water staining but overall in fine condition. Not sure what type of wood, maybe birch or maple. So, the kitchen floors became part of the planned first floor refinish. I called around for professional quotes and I only got one call back. They told me that I should expect at least $6.50 per square foot, which was outside what the treasury could tolerate. (I think the area totals perhaps 800 sq ft.) So, DIY it would be. I read the very helpful Pete's Hardwood Floors wiki and watched a bunch of videos. Here's how I went about the refinishing. Note that we were not living in the house while doing the project.
First I trawled the floors with a drywall knife to find anything sticking out (nails, staple ends etc). I recessed anything I found with a nail set & a hammer. I swept & mopped.
Went to big box store and rented a drum sander and an edge sander. I chose a sanding sequence of 36 grit, 60 grit, 80 grit. I got 6 sandpapers for each of the grits for the drum sander and 12 each for the edge sander.
I started on the kitchen since it was the hardest wood, and since I felt like I could cover it with tile if I ruined it. The old finish was stubborn and I did a 36 grit diagonal pass with the drum sander before a 36 grit pass with the grain. There were multiple spots where the floorboards were uneven or a bit sunken that the drum sander couldn't get which I went at with a hand sander. I tried to hand sand out the water spots but didn't help much.
The foyer with the oak was similar - hard, a good bit of old damage/discoloration. Again, I probably could have got it looking better if I was more experienced and braver... maybe if I started with 24 grit. I got it looking OK, but rustic.
In the LR/DR with the douglas fir, I did just straight passes with the drum sander. The wood got way cleaner and looked beautiful, but it was noticeably softer. The edger sanding was difficult on the softer wood. The machine itself was heavy and awkward and I made multiple whacks and divots. I tried to feather in the edge sanding, but overall the edges are rather noticeably different than the drum sanded portions. Couple spots of damage that I was too chicken to whack at more. I did these rooms together with the drum sander since they are connected (see pictures) making it easier.
Sanding took about 2 full days. Drum sanding was pretty quick. Edging was slower, and hand sanding added time too. Also, maneuvering around extension cords, changing sandpaper, emptying the sander bags, a bit of sweeping as I went - these all took up time.
After I sanded, I swept the floors and then buffed with a square floor buffer machine, using a 120 grit screen over a red pad. This was quick. I think I could have done more with a more aggressive circular buffer to smooth out the edging border, but I didn't really know how and couldn't figure out the right machine to rent. I was pretty over it at this point and ready to move on. At this point, I recognized that I wasn't going to get it looking perfect or professional without a lot more work, but it would look better than before and the price was right! I also rationalized that that the kitchen & foyer floors were kinda beat up anyway and that "rustic" would be the look.
Then came obsessive cleaning. I swept briskly with a broom and vacuumed up the dirt, then went over with a shop vac with a brush vacuum attachment, then swept again, then a very lightly dampened microfiber mop. Other prep included closing the windows (we left one open by accident 🙁 which did create some dust)
Next was sealer. Me and my husband tag teamed this. I went around the edges with the foam edger and he rolled on the rest right behind me. I used one bottle of amberizer for the gallon of sealer we used in the foyer and kitchen, no tint for the douglas fir. 90 minutes after this coat of sealer, per the manufacturer instructions, we mixed and applied the first coat of Supra AT. When the application was initially finished there were a bunch of streak marks and parts of the edges were really obvious, so I was worried we screwed it up. Happily it all evened out in just a couple hours.
Then 3 hours later, we were ready to buff before the second coat. We did unfortunately have some dust bits that had gotten into the finish which I picked out with my fingernails and gently buffed, which seemed to work. Then we buffed the floor with 120 grit sandpaper on a pole sander, then cleaned again (swept, vacuumed and mopped with lightly damped microfiber mop). I think we could have used the floor buffer machine to do this but I wondered if it would be too aggressive or prone to error. Then we did the second coat. Next day it looked just beautiful. Couple bits of errant dust stuck in there but overall very happy. We walked on it a little with socks the next day which mfr instructions say is ok. Now leaving it be to cure for a couple weeks.
In the kitchen, there was much more specks that got into the finish. This is because the room is gutted and despite our best efforts to clean, the open walls are just weeping dust. I might go back and buff the floors again and recoat with another coat of Supra AT in the future, but leaving it be for now.
I read a lot about different products for sealing and finishing the floors. The r/hardwoodfloors sub was helpful for this. I ultimately chose Loba products because they seem to have a reputation for being easy to work with and durable. I decided to do one coat of EasyPrime and two coats of Supra AT in the satin finish. I also liked that I could use the amber tint in any of the coats to get my desired color. I may go back and add another coat of Supra AT with amberizer in it in the kitchen. The floors are a bit cooler than I'd hoped. However altogether I'm happy with the results!
Materials for project, about 800 sq ft or so. Costs for what we spent, but we had some things already on hand:
Preparation: prybar, hammer, infrared heat gun, carbide scraper, painter's multitool, rags, bucket, nail set
Drum sander + 6x 36, 60, and 80 grit sandpaper $350
Edge sander + 12x 36, 60, and 80 grit sandpaper $325
Electric hand sander + 60 & 80 grit sandpaper
Buffer + red pad + 120 grit sanding screen $170
Wet-dry vac with brush vacuum attachment
Microfiber mop
Pole sander with 120 grit sandpaper
2 gallons Loba Easyprime sealer, 4 gallons Loba Supra AT Satin finish, 1 bottle Loba amberizer - $870
3/8 nap roller on a pole - used 3 rollers $15
Foam edger $20
Extra notes
We did the floors before painting the walls or redoing the baseboards. UGH. This was due to timeline and limitations in PTO days… We needed the floors done prior to moving in, but we will be able to do the other stuff while we are living there. We are protecting the floor with construction paper and plastic in the meanwhile. Wish it would have worked out to do this differently.
I should have done samples with the amberizer in differing amounts, but I didn’t because I’m a bum.