Refinishing a floor

[cme4dk]

I am helping my son renovate a house he just bought. The house was built in 1977 and we lifted the carpeting in the 4 second floor bedrooms and found nice looking hardwood floors under the carpet. Upon closer inspection the orange oak hardwood was nailed directly onto the joists, no subfloor.
We removed the nails and staples but when we tried to clean the floor with water, white stains appeared. Earlier this evening I brought over some denatured alcohol and poured some on the floor. The floor did not feel sticky but I was easily able to remove some of the finish using just my fingernail after the alcohol sat for about a minute. I assume the finish is orange shellac.

My plan is to place one coat of the Zinnser sanding sealer which is non waxed shellac, followed by one or two coats of a semi gloss waterborne polyurethane.

What are your thoughts?

[woodsman83192]

I did the same thing a few weeks back. Just bought my first house at 23, wanted to spruce up the Ash floors. Cleaned it with mineral spirits, 1 coat of the Dewaxed Shellac mentioned, and a few coats of Bona Traffic HD. Was worried about it because it's a 2 part and I've never touched the stuff. Used a 9" deck applicator on a broom handle. Went on in a breeze.

Put it on really heavy or it will alligator in thin spots. $120 a gallon but the results are worth it. Keep animals outside where they belong and it will hopefully last for decades.

Do what you can to keep hair and dust off the floor when finishing. Not sure how anyone is able to do that, I can attest. But for the $175 spent on 350 sq ft of hallway and living room, couldn't be happier. Best of luck with the construction! The experts will be along shortly for feedback.

Jake