Per Spencer's request, here's my procedure for cleaning wood.

For gray moldy wood with no stain, or a cheap clear coat such as Thompson's

1) Soak wood thoroughly with
6 ounces/gallon Sodium Percarbonate and 1-2 ounces Sodium Hydroxide plus Dawn.
- for wood with no stain use 6 oz/gallon Percarb, 1 oz/gallon lye, dawn.
- for wood with clear coat use 6 oz/gallon Percarb, 2 oz/gallon lye, dawn.

2) Pressure wash with about 500-1000 psi

3) Neutralize/brighten with 6 ounces/gallon of Oxalic Acid.

Buy chemicals from Univar or your local chemical company in 50 lbs. bags.

You will find this will give you at least twice the chemical for your money for the same results
and some products TEN times your money.

For wood with oil-based stain that needs stripping down to the bare wood, add more Sodium Hydroxide. Furring may result and you may need to sand the wood a little after it dries.

I still refuse to buy any name brand products even if it doesn't fur the wood that much. It is still going to fur some no matter what product you are going to use, so the amount of time you spend sanding the wood after it dries is going to be about the same.

Ask the home owner what kind of stain was used on the deck. Ask for a leftover gallon to see if it is oil-based. Sodium Hydroxide strips oil-based finishes well. If it is oil-latex blend, it will not completely come off. If it is 100% latex, don't even waste your time stripping it. I've given up trying to strip latex, even with Methylene Chloride, it is still a nightmare.

I despise BEHR products. Not only does it look like crap (a$$ in a can), they sell this junk in all kinds of ridiculous concoctions. Oil-latex blends, oil, 100% latex, they all suck.

Tell your customers to avoid it like the plague.

That about covers it Spencer.

I posted all my mixes for roofs, wood, concrete, gutters, and houses.

Thanks Mike!!! Did you ever try to make the powerhouse?

I will. Going to call Univar next week and place an order for more chems.

Mike that seems like some strong chems for cleaning out greyed wood. I've used Bob's F-18 mixed 8-10 ozs. per gallon and then downstreamed onto greyed wood - I also did the same with Russell's HD-80 and both of them cleaned the greyed wood no problem. I figure I am getting about 1 oz per gallon once the solution is on the deck. But then again - that's different from a pump up sprayer - where you are misting a fine solution instead of inundating it with a pressure washer.

I use the Delavan pump for applying chemical. I don't have a hot water burner so I have found adding a little Sodium hydroxide helps the Sodium percarbonate disolve much better and adds strength.

Hot water makes the sodium percarbonate disolve good, but it still helps to strengthen it some with a little lye.

Downstreaming 8 oz/gallon is way too weak for my liking, and does a little more overspray than I'd like. You're getting about the same amount of hydroxide on the wood as my mix but with my mix the extra 6 oz/gallon of sodium percarbonate does make a huge difference.

I run chemicals through my Delavan pump through my 3/8" high pressure hose and I like to use the plastic wand with the cone nozzle, and a 1/2" ball valve on a 3/8" stainless steel coupler. The trigger will eventually stick on you and die, just unscrew the wand and put it on a 1/2" plastic ball valve. NOW YOU HAVE A FAIL SAFE WAND!

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_42897_42897

F-18 and HD-80 are basically Sodium Hydroxide. Univar's price for Sodium Hydroxide is $.70/lb.

Mike, When you order from Univar is there a minimum on the amount you order of certain chems?

Yes, there is a $300 minimum order. Most chemicals come in either 55 gallon drums or 50 lb. bags. They don't sell many chemicals in 15 gallon drums unfortunately. I would like to get isopropol alcolhol and Tergitol NP-9 in 15 gallon drums, but they only sell it in 55 gallon drums. So I just go to Walmart and buy quarts of alcohol. NP-9 I order from chemistry store.