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


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.