cleaning gray decks

[Jersey Bill 17]

I don't have a lot of experience cleaning decks.  Most of my customers want the mold and mildew gone.  I apply my standard house wash, sodium hypochlorite mix with liquid detergent, applied with a pump sprayer to the deck.  I make my mix a lot stronger for decks than siding.  My customers are always happy to have the mildew and mold gone but are pleasantly surprised to see the gray gone too.  I have been reading about brightners, NOAH, sodium hydroxide, and oxalic acid for decks.  My question is for a pressure treated gray dirty deck should i be applying anything else to the deck?  After all my reading I am still unsure why I would use a deck brightner or Oxalic Acid. I do get furries when I am done but not all the time.  I would appreciate any advise.  I work in New Jersey by the shore.  

[Beth n Rod 1,279]

If you are just cleaning a gray deck that has no stain or sealer, you can actually do a better favor to the wood by using a percarbonate instead of the bleach mix for house washing.

Yes, it will get rid of the gray but it also leave behind chemical that on the next wet weather cycle can become active again and degrade the wood.

 

A percarbonate is oxygenated bleach. It has a life of 4-6 hours once mixed with water and applied. After that, it is inert and useless.

This product is harmless to the wood afterwards and actually brightens it without the use of chlorine. It kills mold and helps to remove the gray wood fibers that are caused by exposure to the suns UV rays.

 

Mind you, this can also work on decks having a sealer/stain in place as a maintenance cleaner which has little effect on the coating itself, but will help to remove dirt, mold and prepare the surface for maintenance applications of whatever sealer/stain is in place.

 

This is basically an introductory to one small aspect of wood care  which does not give the topic of wood care the thorough explanation it requires but in the case of your question, it provides an answer to the basics of your question.

 

Too much to go into here. It requires a class and about a week of your time both in a structured educational format and hands on work in the field to begin to understand the many facets of what one should know when it comes to wood care.

I hope in the case of your question, I have helped at least in that regard.

 

Rod

[Jersey Bill 17]

Rod, 

Thanks for the info. I am going to give it a try on my next deck it I can. 

[Trevor C.N 15]

I've been thinking... if a deck is just a bit weathered from 2 - 3 years of sun exposure, why couldn't you just clean it with a brightener (and some TSP or Dawn) and save yourself an extra step (by not applying the precarb to it). Assuming that there is no mold, or milder on the deck, this seems like a viable option.

Edited April 11, 2014 by Trevor C.N

[Beth n Rod 1,279]

Applying a percarb does the job of the brightener without needing to neutralize.

It kills the mold and helps to remove gray wood.

 

Something to consider.

 

Rod

[Trevor C.N 15]

Hey Rod thanks for your comment. 

 

In my experience, the precarb slightly darkens the wood, so I end up using the  brightener anyways. So why not just use a brightener as the only chem on a deck? Of course, i'm only talking about fairly new decks that are just grey - no  mold or mildew.

 

Has anyone done this before? 

[James 625]

Mold will start forming as soon as a deck is laid. Percarb's do darken decks . Percarb's are a pain and don't work well on new wood. They want to lift off what can't be lifted which causes fur balls .

[Trevor C.N 15]

I feel the same way with precarb and new decks. What alternative would you suggest then - a light bleach mix perhaps ? 

[James 625]

Light bleach wash . Pre wet or mist the deck and apply solution and rinse .

[Beth n Rod 1,279]

Anything alkaline will darken a deck to a degree.

 

Beth