Deck Pics and Question?

[svp07 14]

These are pics of a deck I has asked to restore. Today I went to do a test patch because there was a sealer still present on the verticals; even though the owner insisted there was nothing ever on the deck. The sealer came off with the EFC-38 and then I neutralized. However on most of the horizontal surfaces the green mildew is very thick. There are pics of a step I cleaned and the green is still present; another pic of an untouched step and also one of the rails. How do you get this green crap off so you can seal over it? I also tried some bleach and water that did not work to my liking.

[Firedkm 14]

Steve,

Looks like you did not let the cleaner dwell long enough to kill the mold if thats what it is. How long did you let it sit before you did your rinse?

[svp07 14]

Dwell time was about 20, also reapplied again, then sprinkled some on direct and used a brush. Should I use the HD-80, I bought a bucket but have not gotten in to it yet?

Should I let it dwell for about 40...seems like I will have to reapply chem a lot to keep it wet?

[seymore 90]

I would strip it if it was me Steve i'm suprised the bleach didn't make it go away either.

That deck really purple?

Barney owns a place in Joisy ?:)

[Paul B. 523]

Are those undesolved EFV-38 crystals in the first photo?

Bleach will kill the mold - if using household at 6% sodium hypochlorite, mix 1:1 with water. If using liquid pool shock at 12-15%, then dilute 1:3 with water.

Looks like there is stain on the step that needs to be stripped - use your HD-80 and if the mold is still on there, apply the bleach/water mix.

[svp07 14]

First pic - reflection of the flash in the water droplets, pic was taken at a distance of 8 inches, +/-.

I thought it might be stain also but the stuff comes off with the EFC-38. All that is left is the mildew. I am thinking that after a certain point mildew will start to grow something of a "root system" into the wood. I cleaned their flagstone walk and there is a type of green growth that still left a mark when 2000 psi was applied, bleach did nothing to this either. Anymore pressure and I would have been removing sections of stone. I will have to get pics of the other stain or growth on their walkway and upload it in another post...maybe someone can identify it.

[svp07 14]

Pic of deck so you can see the green.

[Everett Abrams 501]

To have the "green" embedded that much you would have to say this deck has not been maintained correctly for some time. When this is the case and you have a heavy build up of mold, mildew, and algae you should go for the stripper and then brighten. After you get a few under your belt you will realize how much easier and better the outcome than using any kind of bleach and even having to go back over it. That isn't even taking into account how much time you will save.

Something to understand about bleach is that it will react with what it hits first. If it has algae on it, then mildew on top of that, and dirt and debris on top of that, guess what? You are spinning wheels and will be reapplying all day. Grab the sodium hydroxide and brighten.

[svp07 14]

Thanks Everett,

Yes the deck has not been maintain, funny because these people live in Upper Saddle River...the houses are ridiculous in this town(!) and they are well-off. The while lot is covered with trees so there is a high moisture content in the air. I will strip and get some experience with that. I am just worried about the sliding door threshold, I quess just keep it rinsed.

Should I try a test section? There are no inconspicuous areas that have the bad mildew.

[Firedkm 14]

Steve,

You can always a spray bottle with oxcalic acid in it an spray the threashold after applying the stripper. This will neutralize it and you wont have any problems with the threashold.

[svp07 14]

I thought about the spray bottle approach; is the oxalic metal friendly? I did not think it was, but to neutralize the caustic on the metal it will be alright...

[Beth n Rod 1,279]

This deck has a severe moisture problem, Everett hit it on the head, sometimes you will have to bring out the big guns in orders to get rid of a problem like this. (sh and neutralize)

I have also wondered if it could be a vein of cca leaching out of the wood since the moisture content is higher and the moss and algae enjoy an acidic environment.

Speculation Everett?

Rod~

[svp07 14]

CCA...please explain?

Moisture is a problem in and around his house. They go to Maine for the whole summer and they say that when they return their is always mold on their basement ceiling. I asphalt drive is also a pretty shade of green.

The verdict is Strip it!

[andye629 14]

try a different type of soap.

[reed 500]

Oxalic or Citralic is not "metal" friendly. Becareful around thresholds it will oxidize.

reed

[Firedkm 14]

I thought about the spray bottle approach; is the oxalic metal friendly? I did not think it was, but to neutralize the caustic on the metal it will be alright...

Steve,

I have not had a problem with this. I just make sure I rinse it down really good when I am done doing the deck

[Beth n Rod 1,279]

cca=Chromated Copper Arsenate

A preservative solution mixed with water and infused by high pressure in a hyperbaric chamber into the wood to help it withstand exposure to ground contact and insect infestation.

Sometimes it leaches out of the wood in viens which contain pores open enough to allow it to escape if an acid has disloged it.

[Beth n Rod 1,279]

cca=Chromated Copper Arsenate

A preservative solution mixed with water and infused by high pressure in a hyperbaric chamber into the wood to help it withstand exposure to ground contact and insect infestation.

Sometimes it leaches out of the wood in viens which contain pores open enough to allow it to escape if an acid has disloged it.

Rod~