help peeling deck

[m Ransley]

They used 2 different products, that does not sound right , stain does not peel unless there was a reaction and the topcoat did not penetrate. Ive never heard of stain peeling, paint yes. Best is remove it all , probably with a power washer. You should find out what products they used and talk to the manufacturer. Warranty or no if they didn`t follow instructions it is their fault. If it won`t power wash off with out damaging the wood you will need stripper. Talk to who made the products for advise.

[Joseph Chong]

I live in Vancouver Canada. We had our deck stained with a semitransparent stain by student painters last June. This rainy winter it has already peeled. The deck is cedar that lays on top of a membrane coated surface, with about a half inch gap supplied by slats i guess they are called. The fence and railings are not peeling, but I am wary. They applied a layer of water based then oil based stain, telling me it was the way to go, now I am realizing that this is not. There is no warranty on deck finishes.

Do you think it was the finish technique or the nature of the weather and deck that caused the peeling? If I redo it now, what would you do? Because the deck is close to but not in touch with water underneath is this the cause of peeling and if so would you then sela the underside of all the deck somehow? (The deck 'floats and is removable is segments so I could do that but it is a huge job.). Is there a recommended type of product to use?

Any suggestions would be welcome. E-mail me at [e-mail]

thanks joseph chong

[Edwin Pawlowski]

I don't think the mixing of latex and oil based was such a good idea, but there may be more to it than just that. My deck was refinished with one of the top brands of latex stain. The vertical portions are fine after five years now, but the horizontal decking peeled away also staring after the first winter. I'm not sure what I'm going to put on it this year, but I know it will be something different.

One of my concerns is that the deck boards may be part of the problem. The are pressure treated lumber, about 17 years old. Over time, some of the pores opened up and the surface is marred with cracking. Over time with the sun beating on it and freezing cycles over the winter, that may be contributing to the early peeling.

[trader4]

"Latex is water soluable"

That means paint should be washing off most of the exteriors of homes, which it obviously isn't. Latex paint is suspended in water in the can. When applied, the particles bind together, forming a tough flexible surface that is no longer water soluble. One of the advantages of latex is that it is more flexible and can allow moisture in the wood to escape without cracking or peeling.

One key question is how is the stain peeling? Is it only one or both of the new stain layers that are peeling off? Or is it peeling from the layers that are now underneath and were there all along? Was it peeling before being painted? It's possible that the oil layer is trapping moisture that previous latex stain allowed to escape from the wood. That wood be my first guess, without knowing more about the location and application. Another key question is was the surface properly prepared before applying the stain? Was it washed clean and any loose material scraped, etc?

[m Ransley]

Latex is water soluable , Ive always used oil on horizontal surfaces and never had an issue. Paint or stain on any surface hot or in sun is bad as products cure to fast and dont penetrate or have time to bond well. All products carry a sun- hot surface warning , it may not be hot out, even at 30f dark surfaces get warm, and at 60+ they can be hot. Product failures are 99% inproper aplication or prep.

[m Ransley]

If you have a water problem with latex paint it is most often on horizontal surfaces where water and snow have been sitting -puddeling, latex when used for the right puropse is superior to oil as in houses that expand and contract. I just would not use latex on floors or decks if I had a choise. Sitting water-snow will affect it, oil stain dries slower and can penetrate better. But a hot surface aplication is worse for latex than oil, hot surface aplication will kill latex longevity

[Hopkins]

"Student painters" -- seems like a nice idea but, as in this case, they come up with some stupid ideas.

I think the water-based stain sealed the wood and the oil-based stain sat on top, having nowhere to go. If treatment is done consistently, there's no reason for 2 coats. If the wood has been neglected, then maybe a 2nd coat. But not right away, and not the same day.

Personally, I would scrape or power wash the loose stuff. The I would wait til next year to re-treat. This will give more time for more peeling and let the stain that's in the wood to wear. If there's not much wear next spring, I'd wait until the fall and do 1 coat of an oil-based stain. If there is good wear or the wood looks dry next spring, then apply 1 coat of oil.

[trader4]

And if he's concerned about the moisture from below traveling up into the wood, then I would never use oil based in that application. Oil based forms a less permeable surface and won't allow the moisture from the wood to escape like latex will. The result can be peeling. I also would never mix oil and latex coats on a job either. IMO, two coats of the same product should have been used on this job.

I agree that the best thing to do now is figure out what was used if you can. Then go to a good paint store and ask them for advice on how to proceed. It sounds like the only logical approach is going to be to remove what's there and start all over. If you're lucky and it's really loose, most of it may come off with a pressure washer. You need to be careful not to use too much pressure and screw up the wood surface though.

[m Ransley]

They used water base first, was it a clear sealer, could it be fine and the oil did not adhere to it? Are there gaps in the wood to allow air movement. It could be a reaction of the latex first coat and oil topcoat that the oil did not bond. Find what they used and call the company that made it. Im sure it wasnt a solid oil stain 2nd coat, soild is paint without the hardner, solid might peel but transparent and semi transparent I have never seen peel direct on wood . At least it comes off easy. A product like Thompsons has wax and nothing will bond to it. If the latex first coat had silicone or another water repellant that could be the issue then you will need to wait till it weathers. I think the 2 products were incompatible.

[Joseph Chong]

Thanks everybody for your input To answer your q it is all the layers that is peeiling. It was a new deck so no previous paint or stain. They washed it with some deck prep stuff prior to application. It was applied in June when the weather was about 20C every day so maybe this is the problem. I know it is going to be a redo job but what do you thinkk about the impact of water under the deck. I am getting some bro-in-law advice that the moisture under the deck is wicking into the cedar, thus lifting the stain off as it tries to evaporate. Therefore the advice is to seal the underside of these removable segments which makes the job at least twice as difficult. jc

[Joseph Chong]

I had a soft spot for these guys as I used to do it also but neglected to remember what a lousy painter I was in June compared to that September. There is NO stain in the wood which is what blows me away. The underlying wood looks as fresh as the day it was cut, not a trace of pigment. I don't even need to pwoerwash to get it off, it is lifting off with a good brush of my broom! When is the best time of year to stain? I thought the wood has to be dry? Remember in the Pacific Northwest it is pretty rainy in the fall.

jc

[Jim Ranieri]

I'm a little confused - a true semi-trans stain should penetrate into the wood and not leave any film on the surface that could peel. Any sort of film former - be it paint, solid stain (oil or latex), etc. is going to fail on a horizontal surface. That failure will be accelerated if dampness is present underneath. My advice - remove the existing finish (if you use a pressure washer, be very careful not to tear up the soft cedar). Let it weather for a year in case there is any residual paraffin from the water sealer, then apply a semi-transparent oil-based stain. This will pigment the wood but not leave a surface film.

[Hopkins]

It doesn't make any sense that a semi-transparent stain would not penetrate. Perhaps it does have something to do with the water under the deck....

btw, why is there standing water under the deck? I have to think it's effecting at least the underside. If you plan to leave the water there, I'd suggest pulling the the parts you can and treating them after they've completely dried.

Are you sure they cleaned it properly and allowed it to dry completely? Maybe they rushed things. I'm thinking you lucked out that both coats are coming off so easily. At least that way you can start, basically, from scratch.

As others have mentioned, you need to find out what exactly they used to seal the deck. I'd also try to find out what they used to clean it. With that information -- and I think you'd have to tell them about the water underneath -- I'd talk to a paint store [I'd go to 2 because some stores have better knowledge than others]. I'd also suggest talking to someone at a lumber yard, and possibly, if there's one in your area, someone at a woodworking store. Just stay away from the home centers.

The following website reccomends a water-repellent preservative a little above a semi-transparent oil-based stain...

You'd have to read the labels, but I don't think 68F is a bad temp for application. Let us know what you find out -- cedar decks are beautiful and uncommon.

[Dr. Joseph Chong]

It snot really standing water, per se. The deck was originally deck-kote type deck. They then laid cedar planks that are elevated on spacers about

3/4 inch high so water doesn't come in contact with actual planks. The underside drains really well. There are no actually standing water areas underneath. I am very grateful for all your help. Cedar decks and fences here are the norm. I guess since it grows everywhere in BC. When I moved here from Toronto, they looked at me bug eyed when I asked about pressure treated lumber for the deck.