This can be a tough one because there are so many ways depending on your experience. I forget who said “practice makes perfect, providing the practice is perfect“ but, If you’ve never done this before, you will almost be an expert when you're finished.

So, for a first timer grab a large paint pad. If there are two of you then 2 paint pads: one for the borders and the other for the body of the floor.

Waterborne Polyurethane Dries Quickly

You’ll want to watch out for two things: hot spots and wind or drafts. Be sure there are no sun spots on the floor from windows. If you do have a “hot spot “ just cover the window with some black plastic. Next, be sure windows and doors are closed. Waterborne polyurethane will not adhere properly should it dry too quickly.

How to Apply First Coat of Waterborne Polyurethane

Ok so now we’re ready. The first person does the edges with the paint pad dipped in the waterborne polyurethane. Go around the edges. If it’s a 10x10 room you’ll want to start at the farthest corner from the door. This will insure you don’t coat yourself into a corner. Coat the border in the farthest half of the room. Then, the second person can coat the body of the floor in the farthest half of the room. Then repeat the same process in the nearest half.

Depending on humidity the floor can take between 30 minutes and up to four hours to dry. If you have a moisture meter take a reading before you start and one when you think the floor is dry. When they match, the floor is dry.

How to Apply Remaining Coats of Waterborne Polyurethane

Now you will sand lightly to remove the grain and raise and break the seal from the first coat. Never use steel wool for this step because residual steel wool will turn to rust when you put on the next coat, which will leave a stain.

Apply your second coat the same way. If you used a waterborne sealer for your first coat, it isn’t compatible with waterborne polyurethane, so be sure to clean or use another paint pad. Apply the second coat as you applied the first coat starting with the border in the farthest corner of the room and finishing with the body of the floor. Repeat in the nearest half of the floor.

This application method may require four coats depending on wood species. If you're doing four coats then apply your third coat by repeating what you did for your second coat. After the third coat dries you must wait until the next day to apply your fourth coat. You can only apply three coats in one day and it is important that the your third coat is as clean as you can get it. Apply the fourth coat the next day, within 24 hours. You won’t have to sand in between as a chemical bond is created within the 24 hour period. Enjoy your floor.