# Cleaning with low pressure



## GMack (Jan 18, 2008)

As a paint contractor, I've done my share of pressure washing over the years, whether it be in preperation for paint or cleaning bare wood. I even thought I knew what I was doing for a while . . . until I got a constant theme from the pros on this board drilled into me: low pressure. 

Today we cleaned a cambarra deck which we stripped and brightened last year. It had grayed quite a bit from the previous year. We wet it. We pre-sprayed it with Cabot Wood Cleaner, scrubbed it, pressure washed it with high pressure, sprayed it with a brightener, and rinsed with low pressure. It looks great and when it dries we will treat it with Penofin.

After we treated it with the cleaner and scrubbed it, all of the gray remained. Couldn't get the gray up without high pressure. (This has always been my experience through the years). Because it was such a dense wood, we got away with a high pressure cleaning but what about dealing with softer woods. 

How do we get the gray up without wailing on it with pressure? What are we doing wrong? Is it the process I'm using or the products? 

We've made some decks look pretty good over the years but I think there is room for improvement in the way we are going about it. Anyone?


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## PressurePros (May 6, 2007)

G,

Cabot's cleaner is nothing but bleach and a little soap. To remove the gray via low pressure (under 1000 psi) you would have to seek out a sodium percarbonate based cleaner or a sodium hydroxide based stripper.


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## GMack (Jan 18, 2008)

PressurePros said:


> G,
> 
> Cabot's cleaner is nothing but bleach and a little soap. To remove the gray via low pressure (under 1000 psi) you would have to seek out a sodium percarbonate based cleaner or a sodium hydroxide based stripper.


Ken,

If it's really that simple than consider me seeking out such a cleaner right now . . . Say I'm using Restor-A-Dek cleaner. Same process? Spray it on, scrub it, and wash it off, this time with low pressure, and all the gray should be gone? 

Thanks Ken


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## Tonyg (Dec 9, 2007)

GMack, how long are you allowing the chems to work for you (keeping wet)before washing? Its possible that you may be rushing the process as well?


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## GMack (Jan 18, 2008)

Tonyg said:


> GMack, how long are you allowing the chems to work for you (keeping wet)before washing? Its possible that you may be rushing the process as well?


Both the cleaner and the brightener are sprayed on, may sit a minute, may sit 10 minutes before we begin scrubbing. By the time they are rinsed off after scrubbing, I'd say they've been on there about 15 to 20 minutes.


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## boman47k (May 10, 2008)

I tend to mist a deck now and then to keep the cleaner wet and activated until I can scrub and rinse it. Whatever area that has cleaner on it gets misted a few times while I am scrubbing.


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## PressurePros (May 6, 2007)

GMack said:


> Ken,
> 
> If it's really that simple than consider me seeking out such a cleaner right now . . . Say I'm using Restor-A-Dek cleaner. Same process? Spray it on, scrub it, and wash it off, this time with low pressure, and all the gray should be gone?
> 
> Thanks Ken


GM, R-A-D is percarbonate based and has some other cleaners and surfactants to release the bond of failing finishes and grayed wood. If you use a pressure washer at say 800 psi you wouldn't need to brush. You'll cut a path right through all the crap as you rinse.

You guys bring up a great point about chemical cleaners. If they dry up, they aren't working.


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## GMack (Jan 18, 2008)

boman47k said:


> I tend to mist a deck now and then to keep the cleaner wet and activated until I can scrub and rinse it. Whatever area that has cleaner on it gets misted a few times while I am scrubbing.


Absolutely,

In direct sun, they dry very fast. I usually don't have to mist them on a cloudy day.


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## GMack (Jan 18, 2008)

PressurePros said:


> GM, R-A-D is percarbonate based and has some other cleaners and surfactants to release the bond of failing finishes and grayed wood. If you use a pressure washer at say 800 psi you wouldn't need to brush. You'll cut a path right through all the crap as you rinse.
> 
> No scrubbing, low pressure, and a clean deck would be a dream. I'll order some in time to test on my own deck before my next cleaning job. I appreciate it, Ken.


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## boman47k (May 10, 2008)

Personally, I feel a waterbroom on a hose would work except for the hard to reach places. I have not tried a broom, and some seem to think it would come off as unprofessional. I can their point. Customer may just get their own broom and try it themselves from then on. You could always put chemicals in unmarked containers and still bedazzle them with the results and claim proprietory information if asked what the chemicals are. And it would be proprietory info. I do know the brooms are lighter and cheaper to work with than a pw'er. 
Just something that lingers in my mind.


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## PressurePros (May 6, 2007)

boman, I think it all depends upon your presentation. Everything can be presented as ultimately professional.

"Mrs. Johnson, one thing we do to protect your deck from damage is to not use a pressure washer. We'll use a landscape friendly cleaner and actually scrub every inch of your deck with special brushes. This type of cleaning is more throrough and will give you a nice even finish on the deck with absolutely no splintering or damage. Since you have little one, the last thing you may want is little shards of wood sticking out all over the place."

Now personally, give me a pressure washer every day of the week. Scrubbing is very labor intensive. Either method works well though.


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## MAK-Deco (Apr 17, 2007)

PressurePros said:


> Now personally, give me a pressure washer every day of the week. Scrubbing is very labor intensive. Either method works well though.


Hey Ken I thought you were an advocate of scrubbing and low pressure?


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## johnthepainter (Apr 1, 2008)

i started out 18 yrs ago with a small electric powerwasher (1800 psi)

then i moved up to a 5 hp gas powerwasher (2300 psi)

then i moved up to a 9 hp honda (3000 psi)

then i moved up to a 13 hp (3700 psi)

heres the funny part>>>>>>> i recently purchased a small electric powerwasher that is nearly identical to the one i began with 18 years ago

so i can relate to your desire to do more with less psi,,,,and rely on the chemicals more 

the last 2 homes ive painted were aluminum sided, and i washed them with the small electric powerwasher,,,,,,,i relied on tsp and bleach for the cleaning action, and didnt have to haul around the big rig,,,,,

the solution did most of the work for me

ill use the bigger rig for serious washing, paint removal, and decks, but some of these cedar homes in good shape, are going to get the small electric powerwasher

i can relate to the thought that this might not look professional (like the scrub brush/hose combo), but as someone already mentioned, you could easly explain that away, (and be perfectly correct) by stating that it would do less damage to the substrate,,,you are relying on the chemicals more

i initally purchased this small unit for stripping and rinsing, but have found myself using it for some light washing

i am set up really well with a great powerwasher, and an excellent selection of wands,,(from a pistol up to a 3 section telescoping wand),,,,,,,,but sometimes less is best


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## PressurePros (May 6, 2007)

MAK-Deco said:


> Hey Ken I thought you were an advocate of scrubbing and low pressure?


Mak, scrubing is not neccessary. Using a pressure washer nozzled down to <1000 psi with the right tip facilitates much faster rinsing. Using a brush is slightly more gentle and safer from potential damage standpoint but as long as your pressure is correct, you are using a good chem, and your washing technique is good, you have no worries. In addition most customers are not willing to pay the aditional $$ for hand scrubbing.


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## johnthepainter (Apr 1, 2008)

occaisionally when im scrubbing or stripping decks, i like to dump a few buckets of sand on the deck and hit it with a stiff bristled brush,,,,,


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