Moisture-cured polyurethane flammability

[nospambob]

[blackbluecat]

Hello,

We're having our floors redone and after reading a lot about this, have decided to go with Moisture-cured polyurethane.

The contractor has objected to it any way he could and in the end it has come down to him doing it provided that I shut off the gas to my building (3 floors, 6 apartments total) because he said that during the first 5 hours of application, the vapors are so flammable that if they sneak out of the apartment and hit someone's oven pilot, for example, it'll start a fire.

I have read about the toxicity of the vapors and the foul smell as I scoured the internet looking for answers, but no one has mentioned any safety concerns.

Is this product THIS dangerous? Shouldn't I then also warn my neighbours not to smoke for those 5 hours? What about electrical sparks inside light switches?

At this point it's very hard for me to draw the line between what's reasonable and what the contractor is trying to use as obstacles to do the job the way we'd like it to be done.

Thanks for any and all answers and apologies for posting this message in another newsgroup.

Happy new year!

[Edwin Pawlowski]

I'm not sure exactly what you are talking about. This is different that water based poly?

I'd start with the directions on the can and then see if the manufacturer has a web page. Contact them for details. Seems like he is over reacting quite a bit, but still worth investigating.

[blackbluecat]

Hi Edwin,

Thanks to you and everyone for your replies.

This is not water-based poly. It's an entirely different thing. It has the glossy shine of oil-based but doesn't turn yellowish over time.

I also feel that he's over-reacting a bit, but was hoping to get some answers here and in another group where I posted this question.

To add to my dilemma, I found today the Maple Flooring Manufacturers' Association's web site and they don't have any moisture-cured polyurethanes in their list of certified/(recommended?) products, so I can't tell whether they don't recommend this finish for maple floors or what. I'm still waiting for someone from that organization to return my phone call (I'll post an update as soon as I learn more so others don't have to go through the hell I'm going through now).

Thanks again!

Edw> > decided to go with Moisture-cured polyurethane.

example,

manufacturer

[effi]

why not ask the contractor his source for the comment on the flammability of the vapors? Either he has a reliable source or he made it up.

per

1. Moisture-cured urethane is solvent-base polyurethane that is more durable and more moisture resistant than other finishes. Moisture-cure urethane comes in non-yellowing and in ambering types. Best left to professionals, they are difficult to apply and have a strong odor.

Is this contractor a "professional" at installing moisture-cured urethane?

[Betsy]

This appears to be an industrial coating. I did a google and only scary things turned up. Here's one:

[effi]

interesting stuff, the op might find this part of particular interest:

"Once dry-a process that generally takes two weeks-the Moisture Cured Urethane coating is considered safe.

Application of Moisture Cured Urethane in occupied homes must be strictly prohibited. "

sounds scary like the potential for problems with cadmium, copper, lead, fiberglass, etc. in a residence...

[tweaked]

[e-mail] wrote in

You should listen to your contractor. Yes, it is dangerous, toxic and flammable. There are better options that are less dangerous and only slightly less durable. Water based poly.

[m Ransley]

Moisture cured- do you mean Water Base?

[Joe Bobst]

Some PU's (and other polymers like Crazy Glue) cure by absorption of H2O from the air. But the resin mix is dissolved in mineral spirts or whatever and that is the fire hazard with poor ventilation. Water based PU's are a whole different kind of chemistry. HTH

Joe