I just finished a wood floor with oil based polyurethane. I only have one coat on now and the fumes are just not conducive to my (very pregnant) wife. Is it possible to put on the remaining coats with water based poly urethane? If so - any brands suggested or ones to avoid?

Get your wife out of there!!!! Serously!

I hope your using a respirator, too! Oils are not to be played around with.

Dude:
Yes, you can top-coat with Water-based. Depending on where you are, wait about 3 days (if high humidity), then abrade lightly, vacuum and top-coat with water-based. Your fumes will be locked in by water-based and all fumes (oil and water) will be practically all gone within 24 hours after laying the water-based.
In the past, I've refinished flooring for an EI patient (Environmental Illness) who is allergic to EVERYTHING including the rays of the tv!! Within 24 hours he walked into the room with absolutely NO reaction. He was amazed . . . I was amazed!
Please, post and let us know a follow-up of how it went.
Charlie

Gus:
By the way, which tri-semester is your wife in? If she's in her 2nd or 3rd tri-mester there's very little chance of danger anyhow.

(Boy or girl?)

After our first 2 girls, a friend of mine was teasing us and saying that I wasn't "man enough to make boys!". I delivered my first son at 4:00 in the morning. So, I called him about 5:30 a.m. and said "It's a boy!!"
I woke him up. he,he
Charlie

Sorry Charlie, but the advice you gave is against all manufacterers recommendations. Most all manufacterers say one cannot top coat oil with water UNTIL the oil is FULLY cured, which can take 30 days or more. While it is possible to do it, it is a risk as the oil is still off gassing. Perhaps he could use a coat of Universal Sealer ( SealCoat ) between the two and thereby speeding up the process. I do agree his soon mother to be wife should not be exposed to those fumes. Even to waterborne fumes. Not till all the finishing is complete and the home has been thoroughly aired out.

Now, why would you challenge my experience with "manufacturer's recommendations"?
I'm a master finisher with a strong background in bio-chemistry. I'm also well versed in hybrid finishes.
So, believe me when I tell you that what I told him is very, very sound advice.
Have you ever done any hybrid finishing?
Charlie

Please note I said "Manufacterer recommendations". Therefore, it is not I who "challanges" you but the manufacterer's themselves. Please specify just one manufacterer who agrees with your opinion that one can safely and without chance of failure, recoat with waterborne over OMU in three days. And I don't have a degree in chemistry. I have been finishing floors for 25 yrs. How about you? As I often tell my customers, floors aren't furniture. What works on furniture will sometimes fail on floors. Finishes I have used include penetrating oils ( Danish, tung, linseed, etc.), OMU, Acid-cured ( Baca-Glitza, Synteco,etc.), Laquers, shellacs, waxes, Moisture curing urethanes, natural varnishes, waterborne acrylics/urethanes. Didn't mean to ruffle your feathers. Just thought I'd mention that the manufacterers of the finishes do not recommend what you are proposing, that's all.

Gary:
Your bringing up "manufacturer recommendations" is not relavent. How many times have you run into these "We don't recommend" because it's the cover-all disclaimer. People in manufacturing, if they don't know for sure, they say "We can't recommend that!". But people on these forums want/need sounds answers based on reasonable experience.
And I talk to other manufacturers who WILL go along with a hybrid finish. (Ever talked to Waterlox guys in Cleveland?) They're the practical ones who have real experience in the field and they know which way is up. I've heard too many people in our trade say "Oh, you CAN'T do that!" when they've never tried it.
My use of finishes is based on the PRINCIPLES of sound chemistry, not the RULES/LAWS. If you follow PRINCIPLES instead of the manufacturers LAWS, whether it's furniture or floors you'll do alright.
You do have 5 years more experience in finishing than I do. I have only been doing this for about 20 years.
Gary, if it came to a judgement call made by you OR a manufacturer, I'd vote for your opinion, because you're the one in the field doing the actual work. How many desk jockeys do you talk to who are "not recommending it", but who have NEVER done a floor in their life.
Besides, I've never had a hybrid finish fail. What does that tell you?
Just my opinion, bro.
Charlie

Thank you all for the responses. You have effectively scared me away from using oil-based in future coats. I am going to take my chances with the water based. I'll let you know how it goes. FYI - Since posting I called the manufacturer of a water based poly and posed the question to them. They said it would be fine to proceed. Anything to sell more product? or good advice?

Just a quick apology to Gary for spouting off this morning. You don't deserve it. Maybe something else was bugging me.

Charlie

Not like you Charley--you're too easy going

thanks

Absolute coating, the makers of last n last oil base polyurethanr and also maker of synergy water base so that you can go over one another as long as they are dry and abraded in between coats. Almost Every job I do has a oil base sealer and water base finishes on them. (the oil base sealer darkens the wood more than the water base sealer).
I have never had any failures!!!!

AH, but we weren't talking about waterbased going over an oil-based SEALER but an OMU. Different products, different purposes, different functions. Bona as well has an oil-based sealer that you can use any of their waterbased floor finishes over after dry. But they say NOT to apply waterbase over an OMU finished floor till that finish is COMPLETELY cured, approx. 30 days. Of course many finishers in our industry ignore manufacterers recommendations and do as they wish. Poly over laquer sealers is common, as is poly over shellac and other quick drying formulations. Does this provide the BEST performing finish or are these "hybrid" systems used to speed the job along? I believe in many cases, "hybrid" systems are used mostly to hurry the job up. Now, if a manufacterer states you can use product "A" with product "B", you can be sure that they have tested that system for compatability. If they say you should not, then there is a reason for that statement and IF the finish does not perform properly, the finisher will only have himself to blame. I know because I've been there, done that. I probably have tried just about every combination ever devised and some have worked, some haven't. I have had to refinish floors that the finish peeled because I mixed systems that were not compatable. So, you live and learn. You will someday think as I do after you have refinished your fifth floor for free and then you will stick to a manufacterer's recommended system and realize that "haste makes waste". Better to take a day longer than to have to redo a floor that the finish failed.

Gary:
I've yet to have a floor finish fail, but I understand where you're coming from.

There was one time where I held my breath and worried. I had put two coats of single component water-based down. I thought for the purpose of flow-out and to give the finish a little "warmth" that I would put the final coat an oil-based. I abraded the water-based the next day after laying it, then put a coat of oil. Later I found out that by all the rules in finishing it should have failed! I HELD MY BREATH AND WAITED. 2 years later the finish was still ok.
I don't understand why it DIDN'T fail.
Take care.
Charlie