Deck Algae

[dj1701]

Hi everyone,

I got me some green ick on my deck. What do you all use to get rid of deck algae, and prevent is from coming back?

Thanks
Dave

 

[EddieWalker]

There are exterior house cleaners that work OK that are sold at Home Depot and Lowes that are considered safe to use around the house, but they don't always get the job done. I personally like Clorox Outdoor Cleaning Bleach with the green label. It's stronger then the blue label that is used for laundry. It will turn your clothes white, right away, and then eat through them so there will be holes after you do laundry. I just put it in a sprayer and soak everything.

For black mold and stronger issues, I'll use liquid Swimming Pool Shok. It's a higher percentage of bleach then the green label stuff, and the results are more significant. Really the only thing that works with rental houses!!!!

Funny thing about the bleach is that I expected it to kill off my lawn when I was spraying down an X pen before letting a puppy use it, but the grass actually looked greener to me a week later. It never died, and there was no sign of where I had sprayed it.

 

[Gary Fowler]

I agree with Eddie, bleach is the cheapest and best for cleaning/killing algae and mold. Even household bleach is better than most "industrial" cleaners. You dont have to wash it down afterwards since sunlight will degrade it quickly, but if you dont like the chlorine odor, wait 1/2 hour and wash it down.
Around here, we get a black mold on the roof if you have oak trees around your house. Bleach kills it quickly.

 

[RNeumann]

Copper sulfate will kill it and prevent growth. Spray it on the deck as needed to prevent and kill- it will depend on how wet the area is.

If the roof is growing algae you can put a strip of copper at the ridge. As it rains it will run down the roof and keep algae away

 

[RNeumann]

How to Clean and Prevent a Mossy Roof | Ask This Old House - YouTube

 

[downsizingnow48]

Ordinary white vinegar the cheapest you can find works great on our redwood deck.

 

[groundcover]

Better on your deck than in your diesel tank !

 

[rekees4300]

Hi everyone,

I got me some green ick on my deck. What do you all use to get rid of deck algae, and prevent is from coming back?

Thanks
Dave

The "algae" is probably mildew. A power sprayer will work but be careful not to use too much pressure in order to avoid damaging the wood. The cause is likely a lack of sunshine so if there's a way to increase Sun exposure it then that will prevent mildew from returning.

 

[dj1701]

The deck is on the south side and gets sun all day. No shade at all.

 

[teejk]

I've heard that ordinary household bleach is bad for wood but oxygenated bleach is ok. There are specialized products meant to handle moss/mold/mildew that you simply apply (I hear ads for "Wet and Forget") but they rely on sun and rain to work and can take a while and in this case you probably want it gone NOW. That slime can be like grease when it gets wet so watch you step.