Deck Coating

I've got a pair of large wooden sundecks that after 25 years of wear are looking weathered and old. They're structurally sound (we live in a very dry area, so rot isn't an issue), but looking tired. They're decked with the 5/4 x 6 round edged decking boards, and I'm not interested in replacing them, since a) they're still sound and b) we're not likely to live here for many more years. I've pressure washed the boards, and they look "less worse" now, and I was contemplating hitting them with a coat of solid colour stain to freshen them up, but I'm not convince of the longevity of that approach. Does anyone have any experience with a roll-on coating for this sort of application? In my mind it would be something like truck bed liner, but I don't have any experience with deck coatings. TIA

Truck bed liner-ish material sounds a bit extreme to me.  How often do you powerwash it?  I would think a good quality deck stain applied after a thorough wash would give you at least a couple years before it could use doing again.

But yeah, UV exposure causes wood to "gray" and old wood with stain on it won't take long to go gray again, so it might take regular maintenance until you decide to replace it with composite decking boards.

There are roll-on products like Tufdek, but I have no firsthand experience.

https://www.ducan.com/deck-coating/default.php

According to my GC friend, the heavy coatings are the tool of the devil. They inevitably start lifting off the surface (probably due to moisture, so it may be less of a concern in your area) and peel, at which point you have no choice but to remove all of it or live with the leprosy look. Solid color stain does tend to hold in moisture and can cause wood to rot more quickly, but again if you're very dry in your area this may not be much of an issue. Personally, I'm a fan of semi-transparent stains for decks if you need it to be a color, but my absolute favorite is Wolman's F&P, which seems to have some kind of an oil/wax coating that works way better than anything else I've tried.

This is what I use. AMAZING PRODUCT

I also have the gloss version of this, I am applying this weekend onmy bench. 

They come in spray can or roll on. I have both. Couldn't be happier.

Don't put that solid paint E36 M3 on there.

Here's my deck as of 30 seconds ago.

The PO painted the rear deck just before before we bought the house (4 years ago.) It has failed in a lot of places and then proceeded to trap water under the parts that didn't. As a result it's rotted out a bunch of boards, particularly around the screws.

It filled a number of the gaps in so the boards don't breathe, based on the humidity under the couple boards I've replaced. 

It's also extremely hard to remove without replacing the deck. Supposedly it will lift if you can heat it to 200+ F (I cleared 2 of 118 boards with a heat gun and paint scraper but it took forever) so I'm going to try a propane torch on it tomorrow. It was clogging my belt sander like crazy if I didn't heat and scrape first.

I usually don't say this about any product, but Rust-Oleum 10x and its ilk are utter berkeleying garbage. And that's being generous.

You're better off with a tinted wood penetrant if you need to cover worn wood. Stuff that actually seals wood and makes it water repellent.

Thanks for the input. In doing more reading, I'm coming around to the view that heavy coatings are an instrument of the devil. The tinted wood penetrant is an interesting idea - any brand names to help the search?

In reply to Turboeric :

Hopefully our construction guys will chime in with a preference but:

• Cabot
• Thompson's
• Restore-a-deck

Are all pretty readily available and will change the color of the wood to hide the general old nastiness. Make sure that they advertise UV and mildew protectioN. Supposedly they last 2 to 4 years between recoating.

I had some kind of Home Depot "stain" on my deck when I moved in. It started peeling almost instantly, and I think it was fresh when I moved in. I ended up having to do all kinds of stuff to get it off... power washing, scraping, and then at the end, sanding. I then coated it with TWP stain (https://www.twpstain.com/) which has lasted pretty well. However I think you'll end up doing it over every couple years regardless. Here are some pics (starting, sanding, and the day I stained it). Also, my deck is cedar instead of pressure treated.

This is my two year old deck and fence, in Florida, which is a really tough environment for wood. Really wet for part of the year, then really dry (although always humid), and lots of sun.

It was spray coated with Thompson's Water seal, two coats on the deck. 

Obviously, both need work. No chance of the fence getting sanded, it's about 120 feet. Deck might get sanded, but if that's a requirement it may end up just getting ignored.

I'm wondering if there's something I can just put right over top of the current finish, either by spray or roll/brush.

In reply to Floating Doc (Forum Supporter) :

I tried Thompson's a few times and never liked it. Same problem as what you're seeing - poor durability and ugly once it started to fail. I think you'll need to pressure wash the remnants off before you do anything else if you want it to stick. For my money you can't beat the Wolman's product I linked to above, but I'm sure there are other good options. The nice thing about the Wolman's stuff is that even when it does start to age out it never leaves that blotchy look; it just fades, and all you have to do is clean and recoat.

While not a magic bullet, I have used Wolman F & P, and agree that it's a good product. 

Read the Consumer Reports tests on deck stain, I say.  And avoid the rubberized “deck restorer” crap like the plague.  It locks moisture in, and causes the wood to rot from the inside out, pressure treated or not.  Ask me how I know ...

In reply to einy (Forum Supporter) :

Excellent suggestion on consulting CR.  I've got painters starting on the outside of my house tomorrow, and I'll ask them as well.

I tried the textured DeckOver stuff from Behr once.  It was awful.  It looked nice for about a year, but it is basically textured latex paint so it remains porous.  When water got on it, the deckover got soft and peeled off.  It lasted about a three months before I ripped all the boards off and replaced them.

I'll +20 the deck covering stuff sucking.  I'm guessing it was invented by the box stores to sell composite decks to people 2 years after they lay that crap down.

I wish mine wasn't painted before I moved in, the original actually held up pretty good, but the repaint failed after a few months.  The paint store guy says they had to change the formula about 5 years ago.

I used Thompson's once. I think the first decent rainstorm took most of it off. I'm a firm believer in Cabot deck stains. 

In reply to 02Pilot :

Will pressure washing take off the Thompson's without damaging the wood? I'm really reluctant to go at it with a pressure washer.

Try this one.

More seriously, in my experience all deck coatings suck and you will need to re-do it every couple of years

In reply to Floating Doc (Forum Supporter) :

It may, depending on how much pressure you apply and how badly degraded the sealant is. Start with a lower pressure/wider nozzle and work up from there.

Because of the pool, may I suggest this?  I've used it on sailboat decks and steps with good results.  I've never mixed it with paint but sprinkled it lightly on tacky paint.  It's about the grain of baby powder, not annoying to bare feet.

Besides just pressure washing, you may want to consider using a deck brightener product.  They're basically a mix containing oxalic acid, and can remove stains and make the wood look more like new.  Most paint stores and big box stores sell it.

It was my understanding that Thompson Water Seal is merely paraffin wax dissolved in a solvent. It wears off after a few years. I have a 30 year old deck with a 60 year old slated awning made of red wood (built after Ronny Raygun chopped down all of the redweed trees and sold them to Japan, it was cheaper than cedar and the same price as treated wood) that every 10 or 20 years I pressure wash off to remove the lichen with a bleach solution and mix one gallon of any colored penetrating stain with 5 gallons of clear penetrating preservative. Some people might do it more often. 

This is an old white paper from the National Park Service about protecting exterior woodwork.  They found that a home made mix of paraffin, exterior varnish, and mineral spirits worked about as well as anything.  https://www.nps.gov/tps/how-to-preserve/tech-notes/Tech-Notes-Windows04.pdf

I used grey Behr Porch and Patio paint on our front wooden porch a couple months ago with no issues. The wood on it is on borrowed time to say the least. The paint applied well and dried fully in an hour or two and has held up so far with all the various weather conditions. If I get a year or two out of this before it starts chipping or peeling, consider me satisfied.