Need deck sealer advice:

[speeder]

I need to re-seal a deck on a house that I'm getting ready to rent out, it has Thompson's Water Sealer on it now and it's failing from the sun exposure. How much prep is necessary with this stuff? I've already dug all of the mulch out from between the boards and I'm about to power wash it really well, do I need to sand the whole thing down before re-coating it?

It's a huge deck and I'm not looking forward to sanding it down...any advice is appreciated as long as you're not just guessing.

Pictures of the worst parts:

[speeder]

I don't know what the wood is, might be redwood which does not even need sealing, AFAIK(?)

[Seahawk]

Pressure wash.

After years of staining I went with the coating stuff, Rustoleum deck restore.

I could not be happier. But, you know where I live so your deck may not see the weather horror mine does.

[afterburn 549]

One think to know 50% wet 50% of the time is purrfect for rot fungus (so i have read).
There is no such think as "dry" rot
So- to seal your wood is just part of a "plan" You must keep it dry too.........and not sun baked

[Hugh R]

Go to Arizona and buy the solvent-based sealer. The water-based crap they sell in Los Angeles doesn't last. When you drive back hide it under your AZ fruits and vegetables before you get to the CA Dept. of Agriculture inspection station on the I-10.

[look 171]

Dennis, it looks like the typical construction grade Doug Fir. From the close up photos, it has a top coat of some kind on there. Are you sure its Thomson's Waterseal? Use a deck wash chemical and pressure wash. I am afraid there's isn't too many products out there to prevent this from happening again. A deck like that will require maintenance every two to three years. I know there is a company that make a thick, very thick paint, maybe epoxy like liquid for decks. It will keep the moisture out from the lumber. Problems is, lumber willl drawer moister from one side instead of both and This WILL cause the decking boards to cup over one season.

[look 171]

Originally Posted by Hugh R

Go to Arizona and buy the solvent-based sealer. The water-based crap they sell in Los Angeles doesn't last. When you drive back hide it under your AZ fruits and vegetables before you get to the CA Dept. of Agriculture inspection station on the I-10.

Hugh,

why under the fruits and vegetables? I have done it with floor finish from Vegas when I restore a smaller Greene and Greene home. I brought my kids and made it a little vacation. I have never heard of anyone getting caught first hand but I am sure it happens.

[flatbutt]

Thompson sux in the sun. I just tried Deck Over for the first time. We'll see how it ages but I'm done with Thompsons. Prep was easy, clean and dry, no sanding.

[Hugh R]

look

It was a joke.

[dad911]

Originally Posted by speeder

...... I'm about to power wash it really well, do I need to sand the whole thing down before re-coating it?

It's a huge deck and I'm not looking forward to sanding it down...any advice is appreciated as long as you're not just guessing.
.......

Originally Posted by Seahawk

Pressure wash.

After years of staining I went with the coating stuff, Rustoleum deck restore.
.....

I'd be guessing about the prep, but we used some Rustoleum deck restore on a plywood exterior deck about a year ago and it's been holding up well.

[Rusty Heap]

Thompsons sux, serious, nothing but paraffin wax. yes it's a sealer..............you can seal wood, or feed it oil as it dries.


I feed my hardwood deck, not seal it.



that said, get a stain stripper, spray it on with a pump wand garden sprayer, wait 10-15 minutes.


pressure wash clean


this is YOUR FRIEND!!!!!!!!!!!!!!!!!!!

awesome rotary large surface pressure washer attachment, I'll never use a wand again for large surfaces.


Shop Briggs & Stratton Rotating Surface Cleaner at Lowes.com

[Bugsinrugs]

Sikkins is the product I use. Oil base and a little pricey. The county I live in ( Nevada) is one of two counties in California that sells it.

[jwgn777]

I know you don't want to do this,if your deck planks are screwed down you can turn the boards around. I gave up on sealer because the top of my deck was shot however when i reversed the boards it looked new and i got another 8 years out of it. Maybe you might want to go with decking paint.

[trekkor]

I once belt sanded a whole deck... Once.

Power wash and do a deck stain/sealer.

Have your tenants maintain it.

KT

[jwgn777]

Originally Posted by trekkor

I once belt sanded a whole deck... Once.

Power wash and do a deck stain/sealer.



KT

The top of my deck was not even sand able that's why i reverse the boards. It really worked. Problem now is i have no more flips left. LOL

Power wash and do a deck stain/sealer.

[Tobra]

I have been told that Ducks Back is the bomb, but in the poking around this thread prompted, saw something called One Time, which sounded interesting.

[speeder]

Thanks, guys. Flipping the boards is clever but would not work due to all the angles on this deck.

The house belongs to my friend and I think that he's resigned to maintaining the deck every couple of years, 2 years is actually good for this climate.

[speeder]

I once belt sanded a whole deck... Once.



Power wash and do a deck stain/sealer.



Have your tenants maintain it.



KT

At the price point of this rental, you don't get people who maintain decks.

[Evans, Marv]

Denis, from the looks of the first three pictures, it looks like there is exposed wood with old stain/sealer of some sort. If there are still areas where there is some kind of coating/sealer, obviously it will be hard to get something to penetrate well & evenly. If you can power wash the old sealer/coating off without damaging the wood, you are good to go. If not, a decent sized belt sander might be needed. I had a redwood deck that I first flipped the planks over & later on belt sanded them later on when I had to treat it again. The cheap stuff lasts for about a year. I finally found a product named Amteco TWP (the TWP is for "Total Wood Perservative"). They have different products, some of which are EPA approved oil based stains & sealers. I used one of their oil based, redwood stains on the deck, and it lasted about 3+ years (YMMV). You might do a search for them. I bought mine from a place east of I-5 across from University Town Center north of S.D. Nothing lasts forever in the sun, but this is the best stain/preservative I found. They sell a lot of it in 55 gallon drums to the government. If you can find a distributor close by, you might consider using it. There aren't many distributors around, since I suspect it's mostly a commercial product. If I remember right, it cost around $40/gal. last time I bought some about 4 years ago.

[Zyglo]

I'd suggest a floor sander which will be a lot faster than a belt sander.

I've gotten xlnt results from a water based stain, but had it done and don't know what they used.

Sikkens is a high end stain; Thompson's is the very low end.