% SH on the wood

If you must use it, only use it for what's it's good for, which is killing mold and even then, the lowest % necessary (1-3ish%)

Celeste
 
I guess I don't understand why we don't want the Sodium hypochlorite sprayed on a deck but we want the caustic based cleaners used.

Sodium hypoclorite is made by sparging Chlorine thru Sodium hydroxide which is caustic.It has a 12 ph also which is very high as ph only reads to 14.

So in essence aren't we spraying a caustic based cleaner when we spray SH.

Someone needs to enlighten me as I haven't cleaned many decks proir to staining or painting.
 
Bleach is a cuastic

You are correct that bleach is a caustic. It is often mis-used which is why some don't like it's use. Used at a percentage of between 1% and 3% with a surfactant (very important) it can clean very well. The problem comes in when it is too strong, or left to dwell too long. Then it works on the natural glue, lignin, which holds the wood fibers together. When this glue gets broken down, the fibers can stand up giving you what is commonly refered to as the fuzzies. (undesirable) Onother issue is that it can also degrade the actual fibers when it is too strong. If these fibers do not get washed off, (which obviously takes more work) the job doesn't look very good. One more point - bleach doen not penetrate the wood well so spores and roots may not always get killed, resulting in more growth even after you seal. Sodium Hydroxide does get the roots and spores better so with heavy growth, sodium hydroxide based cleaners can do a better job of eliminating the growth. Side note: ALWAYS NEUTRALIZE AN ALKALINE CLEANER WHEN USED ON WOOD. Hope this helped. For more instructions, check our training materials and classes, or contact me for assistace.
 
bringing this post back for a some questions. how do you neutralize? do you down stream it then rinse off, apply straight and let it dwell then wash off or do you just spray and leave it on? i picked up some oxalic acid. reading some posts, it looks like around 8-10 oz per gallon? i'm debating on picking up some percarbonate and mixing myself or ordering someone. suggestions?

all i'm really doing with this deck is treating uv damaged fibers
 
I neutralize with ox everytime, also brightens. Im assuming you could xjet it on but have not tried it yet. i always make a batch of ox in pump up and get to town by the time im done spraying help has things packed up n ready to roll. we rinse deck off after 10mins yes always rinse. i use about 10oz per gallon. i have yet to get into percarb yet
 
We have cleaned hundreds of miles of wood fences and decks here in Florida and used bleach to do it. Yes with only a 1% - 2% solution and yes with surfactants. Remember its easy to start weak in % and go up in % but start high and its hard to back up the bus. Let it dwell and dont get in a rush. 1% SH solution usually does the trick. (1/5 the strength of Clorox Bleach)

AC
 
ok, cool, thanks for more info guys.

really trying to get some info on the nuetralizing process. so after cleaning with sh or percarb, apply ox, then what? allow to dwell and just rinse or do you powerwash again?
 
we use an oxalic based brightener after every job regardless of the cleaner or finish remover being used. It not only negates the properties of the cleaner or finish remover it also suppresses the tannin and some discoloration in the wood in addition to brightening the overall surface.

I used to call it "liquid sunshine" on cedar :) night and day transformation after stripping a cedar deck.
 
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