hi

I want to apply a clear sealant on a natural wood floor ( boards are probably a hundred years old, had sanded and stripped off layers of old paint to expose wood again) - but the more I look on home depot or lowe's home pages the more confused I get what sealant to use - they all seem to be geared for treated hard wood floors (and are very expensive)- not for plain untreated boards like my floor is made of - any advice or recommendations for a clear (colorless) sealant for untreated wooden floors? thank you!

 

Is this inside or outside?
If it's inside then you can just apply poly made for floors.

 

Poly is the most common clear coating used on interior floors. Most are rated for floor use but not all so check the label. Expect to need 3 coats, sanding and removing the dust in between. Oil base polys dry to a harder film than water based and they will deepen the colors naturally in the wood along with yellowing some as it ages. Water based poly goes on a little milky but dries and stays clear. It doesn't change the look of the wood any other than giving it a sheen. Personally I prefer the look and better wear you get with oil based poly.
Not sure what you mean by treated hardwood

btw - welcome to the forums!

 

Polyurethane gets my vote as well.

 

my floor is inside - it consists of pine boards basically straight from the lumber mill without prefinish or any other treatment - so this is not the usual prefinished hardwood floor

as an example -this is the usual type of hardwood floor the sealants are for at home depot - but htis is not what I have

Oak Hardwood Flooring - Style: Natural - Cheap Wood Floors

 

There is no reason you cannot use polyurethane.

While I like the amber tint provided by oil based polyurethane, if you're adamant about not adding color you would want to use water based.

 

You would treat your wood floor just like you would a hardwood floor when it comes to finishing. It's all pretty much the same other than softwoods aren't as tough and are easier to mar than hardwoods. The poly doesn't care if it's oak, hickory, pine or whatever.