Fixing a new, failed stain job on new redwood - Deck Stain Stripping Questions and Answers

RE: Fixing a new, failed stain job on new redwood

Scott Paul ~ Restoring Wood & Decks Since 1993 — Mon, 10 Sep 2018 12:46:53 +0000

The oxalic should not harem the stain but it also may not help the rust spots if the rust is under the stain. Do a test spot.

RE: Fixing a new, failed stain job on new redwood

malgyver — Sun, 09 Sep 2018 20:46:26 +0000

I have come to believe these are rust spots. We have been using an angle grinder to cut different old brackets and hardware, etc, during the redecking process. Areas that are out of reach of the flying sparks have none of the problems.

Will a cleaning with oxalic acid harm the stain?

i did strip and brighten one area already, and wondering if I should just leave the other area for a bit to see if the problem actually grows.

RE: Fixing a new, failed stain job on new redwood

Scott Paul ~ Restoring Wood & Decks Since 1993 — Fri, 07 Sep 2018 10:49:20 +0000

One thing you did not wrong is you stained this way too premature. New wood needs to weather and be properly prepped: Staining A New Deck

Also, never sand a deck for prep, especially at 220. This is way to fine a grit and will reducne the stain's ability to proplery soak in.

I think your stain never had a proper chance to cure. This is possibly what caused the mildew or it could have been in the wood already prior to staining.

You will need to strip (not clean) to remove. Brighten the wood after.

Fixing a new, failed stain job on new redwood

malgyver — Thu, 06 Sep 2018 21:36:16 +0000

Hello all,

Thank you in advance for any help. I recently started replacing decking boards on my very large deck, and the few hundred square feet that I did in the past month is starting to mold or mildew. It has gotten very small black spots in many parts of the boards. This is the in the SF bay area, and the weather in the past month has been dry, warm, and the deck gets full sun.

Basically, I purchased Con Heart redwood that was advertised as dry.

I took the wood home, sanded with 220, and then sealed with Preserva Wood Semi-Transparent sealer/stain in the Pacific Redwood Color. Then I attached the decking boards. Within a couple weeks, the black spots appeared. I'm using CAMO hidden deck screws, which have not caused any problems.

After a lot of research, I think the problem is that the Preserva sealer does not have a mildewcide in it. So, I'm guessing I need to get that sealer off, let it dry, and then reseal with a quality product such as TWP, etc. I have built and maintained an IPE deck before, and yearly I would clean it with Oxalic Acid, and reseal, so I am familiar with that procedure.

Before I continue with the plan to clean/strip the deck, I would love to hear input from any folks here confirming my diagnosis, and the exact steps I should take, and the timelines, to redo this new portion of deck. As well, how I should proceed when I continue to buy more new wood to work on other parts of the deck. Many thanks!