Wood – Is it likely that there is lead in the varnish of the old 1930’s hardwood floor

I have done both a refinish and a new install, and did a bunch of research before choosing. These are my generalized conclusions about the different choices:

Linseed / Tung Oil

Pros:

• Easy to apply
• Relatively durable
• Quick curing and drying times

Cons:

• Will darken with age
• Provides very little protection against wood damage

Oil based polyurethane

Pros:

• Durable
• Low maintenance

Cons:

• Long dry times in between coats (~8 hours)
• Long time to fully cure (~30 days).
• Yellows over time
• Strong odor during application and cure
• Requires some skill to apply correctly

Water based polyurethane

Pros:

• Durable
• Low maintenance
• Easy to apply
• Short dry time (~3 hours)
• Short cure time (~7-10 days)

Cons:

• Short dry time requires a "wet edge" when applying.
• Provides less protection than Oil polyurethane

I don't have personal experience with the Tung/Linseed oil approach. Both of the areas which I was working are relatively high traffic, and I did not want to have to worry about damage to the wood surface.

I have seen the Oil-based poly done, and it is a production. It usually results in evacuation from the house because of the VOCs in the finish. The long cure times made it a deal breaker for me, because the areas in question were main walkways in my house.

So, in my case, I chose to go with the water based poly. It is durable, comes in several finishes (satin to high gloss), and is maintenance free for many years. It is easy to apply, and dries very quickly in between coats. It can be applied without specialized brushes or equipment. You can sand, stain, and seal your floors over a weekend, and they will be ready for walking 24 hours later, and will be fully cured a week later. This is a really good choice for a DIYer, and I would not hesitate to use it again in the future.

Your floors are prefinished and likely have an aluminum oxide finish on them which will be tough to sand off and require more time and sandpaper than normal. It also appears to have microbevels as mentioned by previous posts. You will need to either sand to a consistent depth or completely sand these microbevels off. If you do not sand them off completely there will be residual finish in them which will make applying finish to the floor via T-bar or paint pad difficult.

Environmental regulations have made polyurethane less desirable and it levels more poorly than it did previously.

Some of the most durable finishes available for site applied applications include Bona Traffic, Vermont Natural Coatings Polywhey and Basic coatings "Streetshoe". You should choose a finish and then select a stain as recommended by the finish manufacturer. Bona sets up in a few hours and therefore you can seal and do two coats in a day.