How to apply one coat of Quick Dry DuraSeal sealer plus two coats of DuraSeal polyurethane.
Read these directions first because they contain the specific timing directions for DuraSeal.
Then, watch this video to see our t-bar application technique.
Step 1: Vacuum and remove all dust specks
Use a good vacuum to make absolutely sure there is no dust, debris, or foreign matter of any kind left on the floor. It’s best to use a shop vac or canister-style vacuum that uses a wand with a soft bristle brush attachment rather than the upright vacuum you use for carpet.
After you vacuum, wipe the raw wood with a soft, DRY rag (old t-shirts are perfect) to get up the last specks of dust that the vacuum left behind. Then run the vacuum over your dry applicators to eliminate loose fibers.
If the room you are about to coat is adjacent to a floor where you don’t want spills or drips, use blue tape to protect it. Tape down some cardboard at your exit door so you have a safe zone to place your sticky mop and paint pad as you back out of the freshly coated area.
Step 2: Maintain at least 60°F during process
Make sure that at least one window in the room to be coated is open 3″ or more and that you can maintain a temperature of at least 60 degrees Farenheit for the duration of the coating and drying process.
You will improve air exchange and maximize your cure rate if you turn on a fan (like a bathroom vent fan) in an adjacent room to make sure that the coated rooms are emptied of air four to five times an hour.
Open your container of DuraSeal Quick-Dry Sealer (careful – this is a different substance than the DuraSeal polyurethane – check the can!) and decant it into a watering can or other pouring device with a spout. Dampen your coater cover and your paint pad with paint thinner.
Step 4: Begin cutting in with the pad painter
Start at the wall that is furthest from your exit and runs parallel to the wood grain. Pour a 5-inch-wide puddle that runs the entire length of your starting wall, about 3 inches from the wall. Begin cutting in with the pad painter, but don’t cut in the entire room!
Coat a 6-inch border along your entire starting wall and 3 feet along the walls that abut your starting wall. It should look like the photo above.
Step 5: Evenly fill applicator with finish
Charge up your t-bar with polyurethane by dipping the applicator end in the puddle and then pressing lightly against the floor. Do this several times, until the applicator appears evenly filled with finish, but not drippy (similar to how a paint roller feels as it leaves the roller tray).
Step 6: “Snow-plow” the finish in front of the applicator head
Begin at the top corner of your cut-in zone and gently drag your t-bar at a 30º angle, aiming the center of your 18″ t-bar coater at the center of your puddle of polyurethane, effectively “snow-plowing” the finish in front of the applicator head.
Walk in a straight line, parallel to the wall and without stopping, until your t-bar reaches the cut-in section at the far wall. Don’t lean your body weight on the stick; the weight of your two hands on the t-bar is all the pressure you need to lay down the correct amount of polyurethane.
Step 7: Overlap your last pass
Lift your t-bar and gently wring it out by pressing it against the floor that is already wet with polyurethane.
Start from the cut-in zone and overlap your last pass, again dragging the puddle parallel to your starting wall all the way to the wall at the top.
If you’re coating correctly, the puddle will slowly shrink because each pass with the t-bar applicator will leave behind an even film of polyurethane.
Step 8: Cut in another 3 to 4 feet
When you reach the end of the area of the original cut-in zone, rest the t-bar with the applicator in the wet polyurethane (leaving it on the dry wood leaves a permanent mark), and cut in another 3 to 4 feet along the walls at the top and bottom of your next coating zone.
Step 9: Start at corner furthest from exit
Use your pad painter to cut in along every wall you have left, except for your exit. Starting at the corner furthest from your exit and working a 5-foot section at a time, gently mop the polyurethane on with a back-and-forth motion.
Scrape the excess finish down into a puddle at your feet, then go back and blend your coated section into the cut-in zone by pushing the t-bar away from you while you gradually lift it off the ground. Work backward, blending each section into the last, until you reach your exit door.
Switch to the pad painter for the last few strokes.
Step 10: Dry, repeat steps 3 – 9
Allow this layer of sealer to dry undisturbed until it is safe to walk on (approximately 4 hours.) Then, repeat steps 3 to 9, substituting DuraSeal polyurethane for the Quick-Dry Sealer.
Step 11: Warning
If more than eight hours has passed since you applied your Dura-Seal Quick Dry sealer, you must wait overnight, lightly abrade the sealer and remove the dust before applying your first layer of polyurethane.
Step 12: Dry, then lightly etch up layer of dry finish
Allow the first layer of full-strength polyurethane to dry at least overnight. Use a buffer and screen (180-grit) or a pole sander and drywall screen (120-grit) to lightly etch up the layer of dry finish and create a bonding surface. Cut up the used screens and lightly hand-screen edges and corners.
Vacuum up the fine dust caused by the screening, and then tack with a small rag sprinkled with paint thinner (not water!). Repeat steps 3 to 9 to apply your final coat of polyurethane. Be aware that humidity and limited airflow (read: closed windows) can affect the dry time of your polyurethane.
If you begin to screen your floor with the buffer and the screen starts to “build” or “glaze” like the photo above, stop screening!
It means that your previous coat of finish isn’t ready to be recoated yet. Leave it for a few hours and try again.
Wait 24 hours after your final coat of polyurethane before allowing foot traffic or furniture back on your floors and wait at least two weeks to replace large area rugs.
Pete’s Bonus Tips
Heat, humidity and air exchange.
No matter what the season, both oil and waterborne polyurethanes need THREE conditions to cure quickly and thoroughly:
- low humidity
- air exchange
The air has to be DRY because heavy, moisture-laden air literally blocks oxygen from reaching the finish
It needs to be WARM because the chemical reaction that cross-links and cures the finish will not proceed below 65°.
And a constant but gentle source of FRESH, OUTSIDE AIR provides the oxygen that the finish must combine with in order to become a solid and fully cure .
Some tips for creating the perfect curing scenario:
If the interior temperature is likely to fall below 65° at any time during the coating or the first week after coating, turn on the heat!
Don't point a fan directly at the drying floor; it will force dust into the wet finish. Use a fan in an adjacent room like a bathroom or kitchen vent that is connected to the outside, and leave it on. In warm weather you can put a box fan in a window (blowing out!) in an adjacent room. In cold weather, box fans in windows will suck out too much heat - just gap the top a window in each affected room.
High humidity is the most difficult coating condition to deal with. Turning on the AC will bring the interior humidity down, but without opening windows, the evaporating solvents have no place to escape and fresh oxygen can't get in. But opening windows brings the humidity back up. Usually you simply have to resign yourself to longer times between coats and a longer overall curing time during the most humid months.
For oil-based polyurethanes, you should keep one window in the coated room gapped to 3” for two weeks.
Coating with DuraSeal: the TL;DR version
If you’ve coated with DuraSeal before and just need a refresher, here it is, short and sweet:
- Apply one layer of DuraSeal Quick-Dry Sealer
- Wait four hours until it is dry enough to walk on without footprints.
- Apply one layer of DuraSeal polyurethane
- Wait overnight, then screen with 180-grit, vacuum and tack off all remaining dust with paint thinner.
- Apply final layer of DuraSeal polyurethane
Want to add an extra layer of DuraSeal?
That's a great idea, especially in kitchens or foyers. Wait overnight, abrade at 180-grit, vacuum, tack and apply another coat.
If three coats is good, is six coats even better?
Not all at once, no. Adding a third coat of polyurethane after the sealer will add protection, but if you apply any more than that in quick succession, the bottom layers will continue to try to release their solvent through the layers you've added on top. This can lead to the finish lifting and flaking, especially at the edges.
Too many coats too soon can also leave the finish milky and opaque-looking. If you need more than three coats, wait 6-8 weeks between each additional layer.