Gonna clean and finish the deck and not sure which cleaning product would be best. Did a search and found some discussions of oxalic acid vs bleach and power washing pros and cons, but still have some questions.
Local Lowes carries Olmpic Deck Cleaner (contains sodium hypochlorite and sodium hydroxide, ie, bleach?), Jomax (to which bleach may be added), and Flood Dekswood (contains oxalic acid, but not bleach). Also read SW Deckscapes is good (don’t know what active ingredient is).
Deck is on north side of house, with mildew on half dozen boards nearest the house. All wood is grey. Siding is aluminum and I’ve read oxalic acid can damage it, so if I go that way, would I have to be extra careful to keep the cleaner off the siding?. Have a garden sprayer, which Olympic product recommends, but always difficult to get the nozzle to spread correctly…maybe I need a new one? Wouldn’t mind passing on the sprayer and brushing on from a bucket, which Dekswood recommends.
Anyone like any of the products mentioned? Any advice or recommendations of other products?
Thanks.
Replies
Hoov,
I use laundry detergent and bleach. Ive done many decks with this method and had great results. I mop/ brush it on with a small push broom, and scrub brush. I usually use a pretty strong formula and wear safety glassed and gloves. I wouldnt suggest pressure washing it just causes more trouble. Let it soak at least 15 minutes.
The one time I used TSP I felt like it didnt all come out of the wood and messed up the finish.
thats my experience.... I do know others that use the same slurry.
-zen
A painter I know uses chlorine bleach with some gel-type dishwasher detergent mixed in. (This mix in a bucket to feed the suction tube on a pressure washer.) I use it exclusively now. Nice thing about the dishwasher detergent: it leaves windows clean and sparkly after you rinse everything off.
One thing about pressure-cleaning decks: Go easy! It's very temtping to try to "improve" the cleaning by overdoing it, which results in opening the grain of the wood. Deterioration happens really quickly once this happens. I've replaced decks where the people proudly claimed to have pressure-washed them every year.
By the way, I swear by Flood CWF-UV as a finish. Apply heavily, and it will last for years.
<Olmpic Deck Cleaner (contains sodium hypochlorite and sodium hydroxide, ie, bleach?), >
Yeah, sodium hypochlorite is bleach, sodium hydroxide is used as drain cleaner or oven cleaner--I think lye is also sodium hydroxide. If you use it, be careful not to get it on your skin or in your eyes! Of course, oxalic acid isn't good for you either. Oh, you probably know this--don't mix them--i.e. don't mix a base (sodium hypochlorite and sodium hydroxide) with an acid (oxalic).
Lot's of people think one cleaning product works good, so if they mix two it'll really work. Maintenance chief where I used to owrk mixed a fifty five gallon drum of two cleaners--one an acid and one a base and the gases that formed caused him to pass out. Fortunately another worker found him and opened the garage doors to air the place out before more people were hurt (or killed). i think this particular mixture generated free chlorine gas. As outr friend Martha would say, "Not a good thing."
"Have a garden sprayer, which Olympic product recommends, but always difficult to get the nozzle to spread correctly...maybe I need a new one?"
Most of them I have seen just unscrew the nozzel cap and under it you will have 4 holes at the end of the wand. Check for junk. But you can get new wands also.
"Siding is aluminum and I've read oxalic acid can damage it, so if I go that way, would I have to be extra careful to keep the cleaner off the siding?"
Is that on the package? My first experiences with oxalic acid is in StarBrite Hull cleaner (boat). But I suspect that it is a milder solution and there have been no warnings on it that I remember.
And if the deck is cedar the oxalic acid brightners have been very effective. Looks like fresh cedar except that it is "grainer" from the early wood that has worn more than the late wood.
Whatever you use wet down the plants and walls before starting and rinse them well afterwards.
You need two different chemicals to do this right. Buy a bag of pool shock and put it in a 5 gallon bucket half full of water. Stick the pressure cleaner wand into the bottom of the bucket and pull the trigger for a minute or so to get a good mix. Now use the chemical tip and injector to spray the deck down good. Get it good and wet and then let it soak for 10 or 15 minutes or even longer if you're patient. Now use a wide fan tip to wash the deck off. Cover every board but don't get real close or you will damage the wood. If it's not clean enough repeat the process. Now mix up some oxalic acid and spray the deck the same as you did before. Again, let it sit and rinse. It should look like new wood. If you have access to a good janitorial supply house you can also use phosphoric acid which is sometimes sold as Dairy Cleaner. None of these chemicals will hurt anything as long as you rinse well.