How to construct point finite covering in collectionwise normal spaces?

Putting on polyurethane - specific question about floors with spaces?

• Hello! Sortaclarksville foto freek and eskie lover - thank you for the advice on my previous question - One more question. The floors are plank flooring with 1/4 to 1/2 inch space between them (someone called it shiplap). We are going to do a little more fine sanding of some rough spots and tiny splitting of boards at the spaces. Tomorrow we plan to polyurethane. We read the directions on the can. On-line we learned to start at a dry point and bring brush/foam into the wet spot and lift up to minimize brush/foam marks. BUT. What do we do about the spaces? Do we just put the polyurethane on with the large foam and it will just go in the spaces or do we use a brush for the spaces? And which do we do first? And exactly how? Do we use the foam brush on a section of the floor and then immediately brush backwards dry to wet in the spaces? Do we do the spaces first, let them dry and then go back over and do the foam for the whole floor? (We plan to do 3 coats). Thank you!

• Answer:

  I would do the spaces (and in your case, with a little brush the nail holes first) and allow that to dry. This is purely a security measure to ensure that you get the polyurethane into the areas of concern to long term performance. I am a "better safe than sorry" interior designer. Don't apply this first coat in a heavy or sloppy manner, just a thin even coat. (I would probably use a brush for this because sometimes foam falls apart on rough surfaces) Then don't worry about how the other two coats will go over the first coat because you will never see it. Most poly is self leveling, but use a non-yellowing thick formulation that is UVB/UVA protecting like Varathane. (Love this stuff! Just ask when you buy it which roller they recommend for application on rough, uneven surfaces which will give the least amount of bubbling) What you really want to achieve is a smooth finish with as few bubbles as possible so you don't have to sand between coats. In my experience, when you back sweep dry to wet you create bubbles. Once you have that first coat in the cracks, holes and spaces, simply roll the poly on without allowing the excess poly to squeeze down into the cracks. Just go the closest to the edge of each floorboard that you can.