Hot Topics: Deck Stain Prep

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Original Post: Deck Prep For Re-Doing Semi-Transparent Stain

Turbojimmy2 Member

The coating on my deck is about five years old and is coming up. I moved in four years ago, so I don't know who applied it or how. I did find some extra material. It's Behr-brand semi-transparent stain. It's a custom tint, so I'll have to see if I can get Home Depot to duplicate it.

My question is how to prep it for re-staining. I power washed it (just water, no chemicals) and it knocked the really loose stuff off, but it doesn't feel like enough. Do I need to scrape and/or sand?

I'm guessing with a semi-transparent stain that a color change is out of the question without sanding down the entire deck.

deck boards with peeling gray paint

a gray deck with patches of missing paint

Stickshift Group Moderator

“It's Behr-brand semi-transparent stain. It's a custom tint so I'll have to see if I can get them (Home Depot) to duplicate it.”

I wouldn't, you can do better by going to a paint store instead of a paint department.

I don't own a pressure washer, so my process is to spray the deck wet with the hose, spray on a 50/50 bleach/water mixture, scrub with a stiff brush and then rinse clean with the hose.

How drastic a change in color are you trying to achieve?

Marksr Forum Topic Moderator

I'd use an old broom to scrub it with TSP and then rinse with a pressure washer (garden hose also works fine).

From the pics it looks more like a solid stain.

Turbojimmy2 Thread Starter

Thanks. It does look like solid stain, but the can says semi-transparent. They must have put 500 coats on it. I replaced two planks and stained them to try to match. I stopped after five coats—it was close but still didn't match 100%.

Thanks for the reply. I'd do gray again, but a little darker.

Stickshift Group Moderator

If you're going to go a little darker grey, I wouldn't be worried with removing any more of the current stain.

Marksr Forum Topic Moderator

“It does look like solid stain but the can says semi-transparent.”

It's possible they bought both semi-transparent and solid stain, mixed them together and then stored the leftover stain in a semi-transparent bucket.

IMO your deck is iffy for using a semi-transparent stain unless more of the existing stain is removed. A solid deck stain can be used over your deck as is and there are no color restrictions.

Turbojimmy2 Thread Starter

Thanks—I'll have to think about it. I don't really have a preference for either semi-transparent or solid. I was just going to put on whatever was on there previously.

Marksr Forum Topic Moderator

I'm afraid that even with the same color stain in a semi-transparent the 'solid' areas of the existing stain will show through differently.

Turbojimmy2 Thread Starter

Ok—I rented a sander from Home Depot and took care of the trouble spots and then some.

Home Depot still carried the same semi-transparent product. I brought the old can in, but the color label had faded so we couldn't read it. The paint person said the colors hadn't changed since my deck was last done. I guessed at the shade of gray based on the drips on the side of the old can. I chose correctly which made me feel like I won the lottery—do you know how many shades of gray there are (more than 50, I'll tell you that).

Anyway, here are the results. The can calls for a minimum of two coats. After the first, you could see the old stain. After the second it was uniform.

a gray deck cleaned for repaintinga freshly repainted gray deck

Marksr Forum Topic Moderator

Looks good, thanks for the update.

IMO that looks more solid than semi-transparent, but I'm not very familiar with Behr's coatings. Could just be the way it shows in the pic also.

Turbojimmy2 Thread Starter

Thanks!

It definitely appears solid, their definition of "semi-transparent" is off a bit. The first coat is truly semi-transparent—you can see the wood grain through the stain. But they say to do two coats. The second coat makes it appear solid.