What's On My Deck ?? A mystery for you to solve

[PressurePros 248]

I have a customer (RAD) asking me what these spots are. I have a couple ideas but I wanted to get a conference of opinions.

The facts as they have been told to me. Bleach at 6% will not take them away. These spots are spreading. Look at the pics. What do you think?

[PressurePros 248]

Here is an excerpt from my message board:

"We had a new red cedar deck built in April at our home in southern CT. We have recently learned that we should have sealed it within 2-3 weeks, but we did not know this and were waiting for warmer weather. About 3 weeks ago we had three days of rain and then small gray/black spots began appearing on the floor of the deck. They have since started to move up the railings. Nothing we have tried so far will remove them except intense power washing which will damage the wood. We have tried Wolmans deck brite oxygen activated cleaner in high concentrations and even that will not kill whatever these spots are. As a last resort we even tried bleach. It did nothing. The rain line where the water splashes off the roof has no spots. The rest of the deck is covered. If this is mildew shouldn't the bleach kill it? Will your product remove these spots? Thanks for your assistance."

[seymore 90]

I think it's airborne crap falling from the trees or from pollution. :lgwave:

You try Oxalic? I've seen this before and i have a pic somewhere i think it's on another computer when i find it i'll post it.

[PressurePros 248]

I haven't tried anything Shane cuz the customer is 800 miles away. When she was describing the problem I was thinking tannin bleed but now I am not sure.

[RPetry 564]

Ken,

Very weird. Does WRC even have enough tannins to bleed anymore? What is strange is that the deck is only 2 months old.

Some kind of fungus spores? Looks like the "stain" is running down the vertical cedar. You and I in Pa. and NJ have had a very dry spring. Ct. get a lot more rain? Maybe J. Foley who lives in Ct. has some idea.

Got an idea. Call Ed Burke of the Western Red Cedar Association. He is domiciled in S. NY if I recall. Might have an idea. Seriously, the guy certainly seems to know his stuff about cedar, but is a bit off on maintenance.

Shane will vouch for him, they are best buddies.

[seymore 90]

Shane will vouch for him, they are best buddies.

Ed Burke

:bullistic:stupid::bullistic

[PressurePros 248]

LOL Seymore Shane

[jeffex11 121]

it looks like mold but the bleach would have killed that. It may be shotgun mold that bleach won't kill. Cleaner Times Magazine

I usually see this on vinyl siding near mulch beds or wooded areas. VERY hard to get off at all. Degreaser worked some. I actually used gasoline on vinyl because I had no paint thinner available the first time I saw this stuff. i thought it was tar from the new roof they just had installed. do a test spot of course ! power washing will remove some of the outer wood on a deck but on a house this stuff should replace the shuttle tiles that fall off . its HELL to get off but it usually individual dots . this has bleed lines like mold. It could possibly be iron stains from your lawn fertilizer? power wash it whatever it is!

[Beth n Rod 1,279]

Mildew.

Beth

[MMI Enterprises 289]

Seems familiar out my way in that sometimes there will be all this airborne yellowish pollin floating around and sticking to things and then when it is swept or washed away you get this stuff where things had been moist. Seen it on cardboard and pieces of paper just as often as on 2x4's..

P.S.- does look just like mildew as Beth says.. .. you know like on a window sill.. :)

[814jeffw 71]

I would have to try the bleach myself. Maybe they just want you to use an alternative to bleach so they took it out of the picture by saying it didn't work when "they" tried it. Just a thought, as some customers tend to read to much and seem to learn only the negative sides of things like bleach.

Jeff

[Beth n Rod 1,279]

If it is under a clear coat sealer that is relatively new, then it's going to be harder to get to.

Beth

[yazbird8 17]

I read in a recent thread here that wood is being treated with parrafin at the manufacturing end...Is it possible that this black stuff is underneath a coat of parrafin?.........

Stephen Andrews

Power Washing

[Beth n Rod 1,279]

Looks to me like the same effect seen on trex. It's one of two things.

Tannin bleed can be deceiving and in this case it looks like it is proliferating at the splash zone (1st 8"-12" from a horizontal surface) and possibly from wicking in some areas.

If the wood was sealed without proper cleaning then it is mildew.

If the wood is still bare and exposed, it is tannin bleed.

Then there is one more possibility but with cedar it is hard to tell due to the nature of the cellular structure and at this stage is only a guess, but it looks like blue stain. It can be bleached with a 2 step system. 1st a coat of sodium hydroxide and once it has dried, then apply hydrogen peroxide. The reaction of the two creates a highly reactive oxidizer which works on this. Problem for the customer is...they will need a professional to do it. Also, this process could damage the fasteners causing them to corrode even faster.

In the 3rd pic, there are nails both the heads and points visible on a board and the beginnings of tannin bleed associated with wood stress created by using them but the area surrounding it is acting differently.

If they have coniferous trees in the vicinity or other highly pollening varieties, then you have found the contributing source for mildew growth.

Have your customer splash some lemon juice on it and observe the results.

Rod!~

[James 624]

I have had trouble with mold (black) this year on my deck maint's due to the wet year last year. Had to use a very strong bleach solution to get rid of the mold.

I have had rusting problems on new deck's before from the builder cutting metal, but this looks like mold.

You can tell them to call if they want the problem solved. 203- 754 -4284 or 203 558- 0968 cell

[Proclean 14]

Ken,

That is what I started seeing on Siberain Larch about 1 1/2 years ago. Look at this pic. It starts with those small specs and turns to this in less than 1 year. This wood comes from Russia.

Give me a call.

[Beth n Rod 1,279]

Paul,

Yuck!

Thanks for sharing that.

Beth

[Tmrrptr 164]

Is that artillery fungus getting started?

r

[tunatussle 14]

I wonder if the wood may have come from the south(New Orleans area)

and has some type of growth from the area.

[James 624]

Paul ,It's just a combination of mold and degradation from the sun and weather. This past year was wet and moist for Ken's photo ( black mold) I have alot of that.

I have an Ipe deck that looks like that (Paul's Photo) that I"'m letting turn grey then treating with clear to maintain the grey look naturally. I do this treatment with many cedars decks I care for. They all look like the Larch.

[MMI Enterprises 289]

If it same as this you may need about 6%.. lol :)

[plainpainter 217]

Ok - I am ending this discussion with exactly what that is. And the reason I know because it is all over the deck boards on my new utility trailer. Those are little specks of iron from when someone did some metal grinding next to the wood. Even though it looks darkish - that's just the reaction with the rust and the chemicals in the pressure treated. If they scratch some of those spots - they will notice there is nodule or speck of something in the middle of each stain. And if they are lucky to scratch a big enough one - they will reveal the more pronounced reddish color that we all associate with rust. Tell 'em to use oxalic acid and it will clean it right up - mixed with a surfactant to emulsify it somewhat. Ok don't all run up at once with praises of genius.

[Scott Paul 164]

Ok - I am ending this discussion with exactly what that is. And the reason I know because it is all over the deck boards on my new utility trailer. Those are little specks of iron from when someone did some metal grinding next to the wood. Even though it looks darkish - that's just the reaction with the rust and the chemicals in the pressure treated. If they scratch some of those spots - they will notice there is nodule or speck of something in the middle of each stain. And if they are lucky to scratch a big enough one - they will reveal the more pronounced reddish color that we all associate with rust. Tell 'em to use oxalic acid and it will clean it right up - mixed with a surfactant to emulsify it somewhat. Ok don't all run up at once with praises of genius.

I agree. I had a builder leave metal shavings all over the deck last year. Once the water hits it will turn into rust and darken. Try a Phosphoric or Citric brightener. It will go away.

[MMI Enterprises 289]

Ok - I am ending this discussion with exactly what that is. And the reason I know because it is all over the deck boards on my new utility trailer. Those are little specks of iron from when someone did some metal grinding next to the wood. Even though it looks darkish - that's just the reaction with the rust and the chemicals in the pressure treated. If they scratch some of those spots - they will notice there is nodule or speck of something in the middle of each stain. And if they are lucky to scratch a big enough one - they will reveal the more pronounced reddish color that we all associate with rust. Tell 'em to use oxalic acid and it will clean it right up - mixed with a surfactant to emulsify it somewhat. Ok don't all run up at once with praises of genius.

I don't think Ken's pics are of PT, but have seen what you describe when boards lay around on things like sheet metal or concrete. Not sure the effect necesarily points to iron but perhaps more to minerals in general that feed the growth..

[PressurePros 248]

well one way or the other RAD step-1 or Step-2 will take care of it. Thank you everyone for your input.

[James 624]

Metal shards start rusting right away and are not on the verticals and u can pick them out. This is mold I live in CT and have done 100000 sqft already with some BLACK MOLD. Take some stupid straight bleach and pour a little on. Then tell them to call me to handle the rest it's tricky. Rad will not do squat>>>>> on this!

Does anyone remember last year in the East ( CT) ? It Rain for effen 4 month"s and then in fall. I've been through it before.

I have a MAHOG deck I did in the spring pretty big 2500sqft with little black hard specks all over the spindles and nun on the floor. Straight bleach was the solution. I'm not doing it because I have no control over the climate. It stayed wet here for months. All houses painted are peeling and decks are a nightmare that were sealed ( on wet wood).

Part of are biz is to understand climate conditions from year to year and the affect on wood. The Ocean front property I take care had tons of sand on the Mahog deck.It's a 100 yards away and 50 feet higher than the beach ?