How to Remove Mold and Algae From Decks 4.5/5 (19)

This post was updated on January 18, 2022

Removing Mold and Algae From Decks

Deckstainhelp.com is your number one source for deck staining tips and trends on the internet in 2022. Mold and mildew can be problematic for your wood decks, see below for why this happens and what you can do to prevent it. Leave us a comment if you’ve encountered mold and mildew on wood decks.


Moldy_Deck_StainLearning your deck has attracted unwanted mold and algae can be disheartening but it is not the end of the world. These contaminants can be removed to reveal a beautiful surface once again. How to remove mold and algae from decks is a common question asked by homeowners. But with the right knowledge, it can be done over a weekend with no problem.
The key to removing mold and algae from decks is using a quality deck cleaner. Deck cleaners are designed to loosen debris like dirt and gray wood fibers and also rid the deck of contaminants like mold and algae. If the proper cleaner is not used then the mold and algae will continue to grow and will reappear in no time. A deep clean is necessary to get to the root of the mold and algae spores. Not only will a good deck cleaner remove these problematic pollutants, it will also help deter them from coming back so quickly. This is especially important if you are staining the deck. Improper cleaning can mean mold and algae get trapped below the new deck stain and begin to eat away at the wood causing rot and decay.

Apply the deck cleaner thoroughly to the surface as directed. Allow the cleaner adequate time to work. Remove the loosened soil and contaminants with a pressure washer or scrub brush. This should remove any mold, algae, mildew, and graying to reveal clean bare wood. Once the mold and algae have been removed from the deck it can then be stained if desired. Certain deck stains can actually help prevent mold and algae from returning so quickly. However, over time if the pollutants reoccur simply wash the deck again in the same manner. Normally every couple of years the deck should be cleaned for maintenance. The key is to not let mold and algae take over but to clean it often enough to prevent it.

The Best Deck Cleaners for Algae Video – DeckStainHelp.com


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McKeever
McKeever
6 months ago

What to do if you’ve used Rustolem Restore and it’s failing?

Frank
Frank
1 year ago

How do I remove the mold and mildew off my deck without stripping the actual stain on the wood?

Serge
Serge
2 years ago

Cedar Deck couple weeks old.
Black stains all over. Was coated with Tompson water seal, black spots appier, than sanded and I apply penitrating oil, two weeks later , the same

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Serge
Serge
2 years ago

With electric sander that use sanding paper, a part of it i used a planner

james lynch
james lynch
3 years ago

After neutralizing pt deck, if the wood still has a grayish tint, although much cleaner, is there cause for concern before staining? Thanks.

james lynch
james lynch
3 years ago

After cleaning pt wood I can see green coloring when wet, does this mean it isn’t dead? I am beginnin to think I have better chance of ridding the world of original sin than this green stuff….

james lynch
james lynch
3 years ago

Thanks for the quick reply. Any suggestions on the most economical approach to staining spindles? Ever tried using hand spray bottle or is sponge better? If deck stain dries can I reapply if needed?

Denise York
Denise York
4 years ago

Help, I need to get the mold or algea out from in between the floor boards on my deck? What do I use?

Roger
Roger
4 years ago

What deck stain would you recommend for composite decking they all claim to be the best

Tami Phillips
Tami Phillips
5 years ago

I don’t want to remove my stain. I just want to remove the algae. We stainted our deck just last year.

Joyce Richards
Joyce Richards
5 years ago

Can u stain over the mold

Josh Pritchett
Josh Pritchett
5 years ago

Is it necessary to scrub each spindle during the cleaning process or just spray w/ cleaner and wash off?

Liz
Liz
6 years ago

What products are best used to clean and stain a boat dock to prevent contamination of lake?

Steve
Steve
7 years ago

What if the deck has been stain d and a couple of months later the mold shows up
Now what can be done?

Tom
Tom
7 years ago

Is a 50/50 mix of bleach & water a good algae & mildew remover?

aud
aud
7 years ago

great summary but why don't you list products that actually work? we bought the recommended deck cleaner at Menard's have been scrubbing for two days, and still there are mildew and algae stains in teh wood. would like to know the names of some products!

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