Can I apply stain overtop of watersealer?

Question

I have watersealed my deck using Thompson clear watersealer this year. This product specifically. I'm not loving the faded look though already, and I think I'd like to stain it instead. What kind of prep do I need to do in order to successfully stain it? What I'd really like to do is find some kind of semi-transparent purple stain, but I'm concerned that it won't penetrate through the existing clear seal and just be a waste of money. The original product is oil based, so if I use an oil-based semi-transparent stain will that work in well or just fail? This answer on houzz.com seems to imply to me that I can just go ahead with any oil based stain.

The wood itself is Heat Treated S-P-F (Spruce/Pine/Fir) if that's important.

I think I got the whole process backwards, and that I might have to just sand the deck down and start over, but I don't want to do that much work unless I have to.

Answer 1

How much work you will have to do depends on you final result expectation.

You are correct that applying stain over sealant will give you very nonuniform color coverage.

You can choose paint that will provide uniform coverage (by hiding everything), by simply just roughening the surface for better adhesion. Using a primer would help with the paint.

If you want to stain, best option would be to completely remove current coat down to original wood.

Answer 2

It has been many years since I had used the sealer that you have on a deck at my home.

However, I had been informed by a reliable person at the point of purchase that an oil based stain could be added to the the sealer. Then spraying or rolling on the sealer would also stain the deck.

I tried it and was pleased with the results. It did fade in a few years, but I am in Florida with intense sun.

I would suggest you find an inconspicuous area and try as a test. Then add stain to the sealer and seal the deck again. Since it was sealed once you will probably have to add the stain in a more concentrated formula. (the reason for a test area.)

At this point you have nothing to loose, but some time and stain.