# Floor refinishing - polyurethane over "spar urethane" **URL:** \ **Category:** Factual Questions\ **Created:** [July 3, 2018, 4:51pm UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236 "2018-07-03T16:51:46Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Lamoral](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lamoral/32/16078_2.png) [@Lamoral](https://boards.straightdope.com/u/Lamoral)\ **Post date:** [July 3, 2018, 4:51pm UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/1 "2018-07-03T16:51:46Z")
So, I am refinishing one of the rooms in my house and I sanded off all the old finish from the hardwood. I had an old can of Helmsman “Spar Urethane” sitting around and figured I could use that - the can did say “outdoor-indoor.” So I put down a few coats - sanding between coats - and it _looks_ good, but I’ve noticed that it hasn’t built up to the hard and glassy finish I typically can get from polyurethane finish. Then I looked up “Spar Urethane” and found that it _wasn’t_ polyurethane. :smack: The lack of the prefix “poly” should have tipped me off. Well, that explains why I haven’t gotten the texture that I was aiming for - though it _looks_ good. But after sanding, it still has a rather soft and matted look. Don’t get me wrong; it looks good. But what I want is a hard, protective clear-coat over it. Can I get a can of straight polyurethane finish (semi-gloss) and go over it with that? Or will the combination of different finishes somehow fuck it up? Please help! I DO in fact need answer fast, as this project needs to be done as soon as possible so I can get that room back to its functional use. Oh - I should mention that the room is going to be _mostly_ covered by an area rug anyway, so the exposed wood areas aren’t going to get a lot of traffic, if that makes any difference. ---
**Author:** ![Lamoral](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lamoral/32/16078_2.png) [@Lamoral](https://boards.straightdope.com/u/Lamoral)\ **Post date:** [July 3, 2018, 6:42pm UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/2 "2018-07-03T18:42:15Z")
OK - never mind, I have come up with a much better solution to this, so forget it. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [July 3, 2018, 6:47pm UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/3 "2018-07-03T18:47:21Z")
And the much better solution is? ---
**Author:** ![Lamoral](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lamoral/32/16078_2.png) [@Lamoral](https://boards.straightdope.com/u/Lamoral)\ **Post date:** [July 3, 2018, 7:00pm UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/4 "2018-07-03T19:00:19Z")
Numerous thin coats of a higher-quality and faster-drying spar urethane, with extra-fine steel wool in between coats. ---
**Author:** ![Backwater\_Under\_Duck](https://avatars.discourse-cdn.com/v4/letter/b/ba8739/32.png) [@Backwater\_Under\_Duck](https://boards.straightdope.com/u/Backwater_Under_Duck)\ **Post date:** [July 4, 2018, 1:00am UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/5 "2018-07-04T01:00:37Z")
Truly. There is simply no way to fast track it. ---
**Author:** ![Lamoral](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lamoral/32/16078_2.png) [@Lamoral](https://boards.straightdope.com/u/Lamoral)\ **Post date:** [July 4, 2018, 1:08am UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/6 "2018-07-04T01:08:19Z")
Oh, it’s fast-tracked, just reasonably so. This new stuff has a drying time of two hours, and I usually add an hour at least after the recommended drying time. My house is equipped with a whole-house dehumidifier, which helps. I can get 3 coats on in a day. ---
**Author:** ![steatopygia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steatopygia/32/3132_2.png) [@steatopygia](https://boards.straightdope.com/u/steatopygia)\ **Post date:** [July 4, 2018, 3:16am UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/7 "2018-07-04T03:16:42Z")
Spar urethane is specifically _not_ recommended for floors because it is soft. Like really soft. You can put your fingernail in it with no problem. Using fine steel wool and multiple coats _will_ give you a nice gloss finish, but it will never be as hard as polyurethane can be. ---
**Author:** ![Lamoral](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lamoral/32/16078_2.png) [@Lamoral](https://boards.straightdope.com/u/Lamoral)\ **Post date:** [July 4, 2018, 4:11am UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/8 "2018-07-04T04:11:22Z")
Yeah, I know…I noticed that on the can after reading the fine print. Anyway, it’s looking goddamn great at this point, and nobody is going to go into that room with shoes and 75% of it will have an area rug over it anyway, so it will be sufficient for this purpose. ---
**Author:** ![steatopygia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steatopygia/32/3132_2.png) [@steatopygia](https://boards.straightdope.com/u/steatopygia)\ **Post date:** [July 4, 2018, 4:18am UTC](https://boards.straightdope.com/t/floor-refinishing-polyurethane-over-spar-urethane/817236/9 "2018-07-04T04:18:00Z")
That’s the spirit! 😃