pressure_wash_railsWe suggest that only experienced professionals use a power washer when deck cleaning or exterior wood cleaning. That being said, it will obviously make your deck cleaning a lot quicker if you do use a power washer. If you use a power washer please follow these guidelines.
  • Always use a deck cleaner and or a deck stripper. The cleaners do 90% of the work.
  • Use the power washer as a high pressure rinse off. Never as the only tool to remove or clean the wood.
  • Wash with a motion similar to sweeping of broom (pendulum motion). Wash with the grain of the wood. Exaggerate your sweeping motion, never stop and reverse your direction without sweeping up. Not doing this will result in a "stop" mark on your decking.
  • Never use more than 1200 psi of pressure. This does not mean you cannot use a 3000 psi machine. It is only 3000 psi if you are washing from 1 inch away. If you are 8-12 inches away you will be using about half the amount of pressure.
  • Always use extreme caution when using a power washer. Improper use could result in severe damage to wood. If you do not feel qualified, contact a professional in your area.

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re: Follow up on sanding
Yes that could create issues with stain absorption.
Follow up on sanding
Thanks again for the quick reply!

Is it problematic to sand with a belt sander? Is the problem that it might "close-up" the wood and not allow penetration or is there a different reason?

Thanks again, this has been very helpful.
Lightly hand sand slivers is okay before you clean and brighten the wood.
follow-up on sanding
Thanks for the reply!

If the deck has potential for slivers, i should sand it right? and sand it before doing anything else?
re: steps for old deck never stained
You are correct but you do not need to sand the deck so you can skip that step.
re: caulking/wood filler
No you cannot use wood filler on outside wood. It will not work.
caulking/wood filler
Can poly eurathane caulking or wood filler be used in cracks? IF so, at what point should this be applied?
steps for old deck never stained
4 year old PT deck that has never been stained. Just treated once with a wood preservative. What steps do i follow to stain deck?

1) Level
2) Sand
3) Wet deck
4) Apply cleaner
5) Rinse with pressure washer
6) Apply wood brightener
7) Wait 48 hours or until dry
8 Apply stain

Is this right? Do I sand before applying any cleaner or brightener?

re: Powerwashed/str ipped without stripper /cleaner
Surface damage.
Powerwashed/str ipped without stripper /cleaner
I had to take off BM Arborcoat that was peeling badly. Other sites had said that deck strippers do not remove this product well so I did most of the job with just a PWer. The worst peeling areas came off easy with the PWer. However, other areas that were not peeling required a lot of water pressure. The wood is 5/4 cedar with tight knots. Yes I have left some marks with the PWer that I intend to sand. Yes I definitely did use more than 1200 psi. (The PWer is a 2600psi.) I used the widest (40 degree) spray attachment but I did hold it close in some areas.

Do you tell people not to do this to avoid surface damage (ie marks) or have I irrevocably damaged the cedar decking by applying that much water directly at high pressure into the wood?

I have about 25% of the deck left to do and most of that has little to no peeling occurring so I expect it would be tough to take off with just the PWer.
re: N.C. deck abuse
The only way to fill cracks is to use a solid stain and that will look like a paint. We sell semi-transparen ts and since this wood is dried out and neglected, we would suggest the Armstrong Clark in one of the semi-solid colors. You can spray it on but you will need to back wipe to ensure uniformity.
N.C. deck abuse
Hi, I just purchased a short sale home in the northern mountains of Asheville. The deck has been up for 4 years and is showing splitting and chipping from the weather. It has never been stained or coated.We have a normal mix of Summer sun, Fall/ spring rain, Winter rain ,snow and some ice. No mold to speak of, so the deck does get the Southern sun. What is the best product for this issue. I was looking at Olympic solid color stains to fill the cracks but its a Lowes product..... I was looking at TWP or Armstrong Clark with a basic sprayer.What direction should I go? Do I need the professional sprayer? I plan on ordering these products ASAP.
Thank you.
I also have this to add; Make sure that you're strong enough to handle it.

I've seen quite a few incidents where people have gotten some minor injuries from using a pressure washer they weren't strong enough to handle. They're very powerful machines, and even the spray can cause you a few bruises at close range.