water- or oil-based poly?

[Michael MacDonald]

Anyone ever used water-based poly instead of oil-based? or perhaps acid-based (brand is Synteko Calssic)?

This would be over an oil-based stain on flooring... it is sort of a second "do-over" for the main staircase in my house (yes... third attempt... that's right), so I don't want to get creative and screw it up again.

I understand the water-based polys are stronger than they used to be and don't yellow with age. The acid-based is recommended for beauty, but has powerful fumes... and takes two months to fully cure--though only four hours to be usable.

Regards,
michael

[Brice Burrell]

Are you trying to match any existing flooring? There are a number of premium water- based products out there. That said, you know what you'll get with good old oil poly, it's cheap and it has a proven track record.

[Van Huskey]

Even with the inherent negatives with oil based poly, on a floor I wouldn't think twice and would use oil based poly. As Brice pointed out the track record is so compelling.

[Lee Schierer]

I used Varathane Diamond Floor finish on a bathroom vanity. I was pleased with the application and lack of coloration to the base wood. It didn't raise the grain like other water based finishes I've tried.


I would use it for other projects but it only comes in gallon size which isn't always convenient for small sized projects.

[Michael MacDonald]

yes... I am trying to match the surrounding flooring. what kind of difference in impact would I see? oil-based has less impact on color than water-based?

[Mike Cruz]

I love the durability of oil based poly.

Also, my experience with water based poly left me with a frown. It had a blue tint to it. It dulled the wood. It was put over cherry, and I HATED it.

[Michael MacDonald]

I think complaints on water-based were usually around hardness... but I have heard that has improved. hadn't heard there is any discoloration... I have heard oil-based poly yellows with age...

the finisher is recommending acid-based poly... I am reading the specs of the Synteko, and it sounds OK but is a pain to apply... the finisher says it will enhance the grain better than oil or water-based...

[John Mark Lane]

Don't know anything about acid-based, but I've used water based several times and was not impressed. I really wanted to like it, for all the right reasons, but just couldn't. I think I still have some of it, but will likely toss it at some point. I've done many floors, and wouldn't even consider using the stuff on a floor. Oil based poly only for me.

[Carroll Courtney]

Can WB go over OB????I really don't know,just asking----Carroll

[Julian Wong]

Can WB go over OB????I really don't know,just asking----Carroll

If you lay down later of shellac in between, it'll be fine, but have not done it for flooring though. Furniture pieces yes.

[Mike Henderson]

My experience with water base is that it's very clear. We're all accustom to the slight orange tint that oil base has so the water base doesn't look "right". If you shoot a coat of regular orange shellac (dewaxed) first, it will significantly improve the look of the water base finish, and will better match oil base nearby.

Mike

[Callan Campbell]

We're in the slow process of redoing all our wood floors. I put Miniwax stain down on our oak floor since my wife wanted to keep most of the amber color that the old floors had without totally losing the grain in the process. We waited a day or two before coating the now dry stained floor with dewaxed shellac. Then applied Zinsser's water base floor poly over that. Most people seem to err on the side of caution and recommend the dewaxed shellac as a sealer instead of putting the water poly right on top of the oil based stain. It came out great for us, and that's with really high humidity throughout the whole floor process of our bedroom since we were stuck with a multiple rainy day week. We don't expect the water clear poly to amber or darken as much as a oil based poly would over the oil stain, and the shellac was clear and not orange to begin with. From what I've read, that should be an accurate expectation over time.
The water based poly is supposed to be more scratch resistant than oil based poly, but not as alcohol or heavy solvent resistant, so we just have to hold our liquor well and keep our Naptha or mineral spirit spills to a minimum on our bedroom floor, and any other floor we redo.:p:p:p
Some floor guys will "hot coat" the water based poly, by relying on the chemical binding of multiple coats in one day without any "screening" or scuffing of the dried finish between coats. I'm too chicken to try this on my own floors, instead I follow the directions and apply no more than 3 coats in one day. I also lightly "sand" between the coats with floor screen abrasive since our working conditions include 1 cat and 1 dog, which means the odd fur or hair floating around and getting into your now dried finish. The scuffingalso helps the water based poly bind to the next coat even though it doesn't need it as much as a reactive finish like the oil based urethanes do. Water based polys are coalescing, which means they are a bit of evaporative and reactive[picture shellac and lacquer as evap, and varnish/urethane as reactive] combined. So, they bite/lock into and dissolve a bit into each coat as you apply it , giving you two ways of adhering to the previous layer.
Urethane isn't thrilled about attaching to its own previously applied coat, so mechanical scuffing with an abrasive between coats is more of a must for the oil based products.
If you DO want to apply the water poly right over the oil based stain, everything I've read suggests at least 48 hours with dry conditions, or more time if needed before applying it due to the oil stain not being fully cured like the humid conditions we were working with. Using the shellac sealer prevents the water based poly from adhering right to the wood since you're added a layer of finish, so you've got to get the shellac layer right in order to prevent the upper poly layers from having poor grip to it. This means letting it dry more in humid conditions than the can it came in possibly suggests. As always, if you have a closet or unseen space of flooring you can experiment with first, rather than the main field of flooring, this keeps you from losing it if your hard work looks bad after an hour or two of applying your finish.:mad:
Lastly, I HAVE applied water based poly over orange, regular shellac successfully, but dewaxed shellac, either clear or orange, is the stated norm for use as a sealer in this application due to possible wax binding issues with the top coats if you're using regular shellac. Hope this helps you out. I highly recommend Bob Flexner's "Understanding Wood Finishing" Book as a way to wade through the chemistry of the different finishes and how they interact. He takes alot of the fear out and you end up understanding how we make easy mistakes with all the conflicting info out there on wood finishing.

[Gary Muto]

Callan,
Nice summary. I'll just say that I've used water based poly over oil stain and have had no problems. I did wait about a week after staining (due to scheduling). The newer polys are less blue, at least to me. I've also read, and been told that the oild based polys aren't as tough as they used to be due to lowering VOCs and that the new waterbased polys are tougher than they used to be so the gap has narrowed. I can't speak to that but I'm hoping the water based product won't yellow like the oil based finish and that's why I chose to use it.

[Steve Schoene]

Remember that we are talking floors. Run of the mill products, oil based varnish with polyurethane, or waterborne acyrlic with polyurethane, such as you might find in a big box store or local paint store, just aren't in the same league as the floor finish products sold under brands specifically target to floor finishes. (Notice my descriptions--just calling a product poly doesn't say very much waterborne and oil based are completely different products even if they both have a bit of added polyurethane resin.)

Brands such an Bona Kemi or Basic Coatings are where you should be looking.

[Callan Campbell]

Callan,
Nice summary. I'll just say that I've used water based poly over oil stain and have had no problems. I did wait about a week after staining (due to scheduling). The newer polys are less blue, at least to me. I've also read, and been told that the oild based polys aren't as tough as they used to be due to lowering VOCs and that the new waterbased polys are tougher than they used to be so the gap has narrowed. I can't speak to that but I'm hoping the water based product won't yellow like the oil based finish and that's why I chose to use it.
Thanks for the vote of confidence!;) It makes sense that the formulas have had to change due to the new VOC limits on everything, my largest reason for the switch from oil based to water poly is that for floor work, my wife would not be able to handle the solvents drying due to her asthma. She was not nearly as bad back in '96 when I did our kitchen with regular oil urethane, but time changes us all.:(
And with a closed house due to weather issues, the water based works out alot better for both of us.
I also use water based finishes on any projects I'm building, but since I can work out in the garage and not inside, I'm able to juggle just what I want to use in a oil base versus water based decision. For me, it's still a mix of both, with me leaning more towards water based due to the easier clean-up. That lack of depth thing with water finishes is still a bit glaring, oil based sure still has it beat on that unless you put some sealing coat under the water based first.

[Michael MacDonald]

ask and you shall receive... you guys are a wealth of information.

the finisher did say that he would have to wait for complete dry before applying water-based over the stain. (I am not doing this... while the important work gets done, I have a day job.) He did not mention a layer of shellac.

the finisher also thought that water-based had overtaken oil-based in terms of hardness, but he did not mention the alcohol/solvent risk. I don't usually spill solvent unless I have had a lot of alcohol, so I should be OK there. He pushed the acid-based... better enhancement to the wood but nasty vapors.

I haven't decided yet, but now at least I have a lot of info to process to help make the decision. Thanks...

[Callan Campbell]

Remember that we are talking floors. Run of the mill products, oil based varnish with polyurethane, or waterborne acyrlic with polyurethane, such as you might find in a big box store or local paint store, just aren't in the same league as the floor finish products sold under brands specifically target to floor finishes. (Notice my descriptions--just calling a product poly doesn't say very much waterborne and oil based are completely different products even if they both have a bit of added polyurethane resin.)

Brands such an Bona Kemi or Basic Coatings are where you should be looking.
Correct, I'm only talking about floor finishes with respect to what the OP first asked about. Those are 2 respected companies. I've added what I also use for other projects, non-floor, as an additional info on how it's all changing due to VOC limits for all the manufs. who make ALL types of finishes. I'm not sure I got this right, but I believe Southern Calif. might just write off Evaporative finishes like all the lacquers and 2 stage stuff if some laws are rewritten to lower the VOC's even more. I read that somewhere from a posting out of Calif recently, maybe someone can add to it or state where it's coming from.
With respect to Bona Kemi, I've read a posted letter they put out stating how they're not recommending Murphy's Oil Soap as a maint. product for wood floors. Apparently they've done some testing and Murphy's leaves too much residue on a coated floor for their liking. They're worried about contamination when the floors are then refinished at a later date. Interesting stuff, since they went to the trouble of working out a test to figure this all out. Nice to know .

[Paul Johnstone]

Can WB go over OB????I really don't know,just asking----Carroll

Yes, just scuff it with fine grit sandpaper before applying.

Some people will put down the first coat as oil based to get the nice amber tint oil gives you, and then the 2nd/3rd coat in waterbased for the ease of water based. Although my buddy tried it, and thinks all oil based is better looking.

[Mark Woodmark]

Even with the inherent negatives with oil based poly, on a floor I wouldn't think twice and would use oil based poly. As Brice pointed out the track record is so compelling.

I second that

[Jim Becker]

I'm using a water based product on the flooring I'm installing shortly in the 250 year old portion of our home. I used it on a large patch in another room and was pleased with the results. While I'm not normally enamored in any way with products that carry the Minwax name, this was purchased from the local Sherwin Williams store (same company) and was not inexpensive, either, at $64 a gallon. It went on beautifully, leveled beautifully and provided a consistent sheen.

Please note that for this particular project, which is wide white (pumpkin) pine, BLO was first applied and sealed with de-waxed shellac. So I cannot comment on any "color" related issues around the water based product I used since the oil and shellac would have greatly influenced that.