Poly coating

[RobHowarth]

Greetings and salutations.
The house I am currently paying the bank to live in, has T & G jarrah floorboards. A previous occupant has covered these with some form of poly coating. I have no idea what coating was used. Due to the impact of my two sons and life in general this coating is looking decidedly worse for wear and in some areas is worn through to the bare boards.
Some years ago I experienced some health problems while using poly and have been reluctant to use it since. However, I have been told that the new stuff is far more user friendly. Therefore I have two questions
1. Can I use the new water based poly over an unknown previous finish
2. Are the new poly finishes `more user friendly' than the previous `bad ****' chemicals.
Thanks in anticipation.

[Shane Watson]

I would suggest that if the old coating is that badly worn then a total sanding & repolish would be needed anyway. But FYI,

The general thought on two different coatings being applied on top of each other, is that it shouldn't be done. Although it is possible and generally may not produce any problems. The main area of concern is the lack of adhesion from one product to the other where 'Delamination' can occur. Although there are products on the market that are used as a binder between two different products. But from my experience have found these to be of little help.

If you have reactions to poly's, then there are alternatives to use. Although if using the correct safety equiptment you should be protected. And no that dosn't mean using a dust mask where a gas mask should be used, like gets shown on TV.

You may want to experiment a little and do some spot testing to see what is going to work for you. I would even do a cross hatch test to test for good adhesion between coats if you decide to just recoat over top of the old coating.

This Cross Hatch test would simply involve finishing a small section and allowing to dry as normal and then with a razor blade simply cut a cross hatch ( xxx ) into the finish and see if the top coatings come away easily from the previous coatings. This will give you a good idea of whether there has been any adhesion between the two coats. If the top coating simply flakes away, then you have little or no adhesion. Might be a fiddley test - but may save you time and money down the track....

HTH.

Cheers.



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Shane Watson..

Combine Love & Skill & You Can Expect A Masterpiece!