deck power washing

[Orion]

Originally Posted by LIforrelaxin

I have two decks which are approaching 20 years old. Both made with Preasure treated wood, and they have held up well over the years. In 20 years, they haven't been touched, and well finally last year I decided to do just that. ..........

20-year old PT decking is definitely not the same as the new (less than 10 year-old) stuff. I have similar decks at one house that are close to 30 years old and are still solid. The decking I have at the lake has boards rotting at 8 years and less. Granted, there is more humidity at the lake, but PT is supposed to hold up to moisture, and doesn't any more. When they changed the PT formula, along with the newer less-dense pine stock, we got a much less durable product. It does require regular treatment, which I am averse to doing over water on the dock.

[Denny Crane]

Decks should be maintained every 2 years. That's all the semi-transparent and clear stains hold up for from UV light and weathering. If a deck has been sitting untouched for over 5 years, never mind 10 years, of course it's going to take some pressure to remove years of mildew and weathering. If you have the time and energy to hand apply chemicals and then manually scrub every floor board and railing great. No thanks, I'll powerwash. A deck that's been maintained correctly every 2 years will not require an aggressive powerwash, nor will the wood look like the earlier post.
DC

[LIforrelaxin]

Originally Posted by Orion

20-year old PT decking is definitely not the same as the new (less than 10 year-old) stuff. I have similar decks at one house that are close to 30 years old and are still solid. The decking I have at the lake has boards rotting at 8 years and less. Granted, there is more humidity at the lake, but PT is supposed to hold up to moisture, and doesn't any more. When they changed the PT formula, along with the newer less-dense pine stock, we got a much less durable product. It does require regular treatment, which I am averse to doing over water on the dock.

Are you sure the boards you got where Pressure treated, and not just Thompsonized?

The Thompsonized wood doesn't hold up nearly was well as true pressure treated wood does.

[mountainhouse]

I'll add my .01 cent. I have had decks for decades and now looking back to all the power washing, both professional and homeowner, I would only sand with a rental drum floor sander (rent at Homedepot). Under the railing I use a small belt sander. Like new and smooth, and even the less expensive paints stick and hold. It is all about creating the best binding of paint/stain to wood.
But seriously, I would no longer consider anything but composite, now that the product has evolved. Adding up the time-money-other efforts, and in the end , it's still wood (unless one has teak or mahogany )

[camp guy]

I had several decks, walkways, and steps, all pressure treated, and some areas subject to a lot of dripping from trees, and I used the "SAB1" method of a bristle brush and elbow grease, plus I used a garden hose with adjustable nozzle to wash away the debris. I did this each early summer, and it worked well. The garden hose is not so aggressive it damages the wood, but, at the same time, it does wash away debris and leaves the deck looking good.

(I have to laugh at this post - one question, multiple, multiple answers.)

[Denny Crane]

Originally Posted by mountainhouse

I'll add my .01 cent. I have had decks for decades and now looking back to all the power washing, both professional and homeowner, I would only sand with a rental drum floor sander (rent at Homedepot). Under the railing I use a small belt sander. Like new and smooth, and even the less expensive paints stick and hold. It is all about creating the best binding of paint/stain to wood.
But seriously, I would no longer consider anything but composite, now that the product has evolved. Adding up the time-money-other efforts, and in the end , it's still wood (unless one has teak or mahogany )

I've thought about composite but can't do it! There's something about looking out into the woods from a slick plastic deck past the shiny white railings that doesn't feel right in NH! Also, even though the products have come a long way and even look like wood now, there are plenty of product failures such as fading and blotchiness that have led to class action lawsuits(timbertech). It will still need powerwashing!

[BroadHopper]

My 'rich' neighbor pressure washes just about everything on his property. From what I see, never pressure wash vehicles or boats. You should see his tires! Bits and pieces of rubber every where. Even the moldings around the windows on his car, boat and house are shot. Of course he has the money to buy new every year but I would not buy from him!
His gel coat looks great but after he pressure wash it badly needs a 'Diamond Shine'. Even his trex deck looks like it is years old. Not sure if he is using too much pressure but he loves using that thing!

I have a pressure treated lumber dock built before DES put a stop on all the good stuff. The dock been creosoted for years until it was banned. It is now 30 years old and still looks great! I just scrub it every year with a stiff brush. May not look like the neighbor's dock, but I bet it will last a lot longer.

[SAB1]

Originally Posted by mountainhouse

I'll add my .01 cent. I have had decks for decades and now looking back to all the power washing, both professional and homeowner, I would only sand with a rental drum floor sander (rent at Homedepot). Under the railing I use a small belt sander. Like new and smooth, and even the less expensive paints stick and hold. It is all about creating the best binding of paint/stain to wood.
But seriously, I would no longer consider anything but composite, now that the product has evolved. Adding up the time-money-other efforts, and in the end , it's still wood (unless one has teak or mahogany )

Right with you Mountain. Just did that by hand also. Looks almost new.

I understand the pressure washing thing. It comes out looking nice and requires very little physical effort. Easy man's way out and we as American's love to subscribe to this philosophy in many ways. Heck that's why I did it! But it is a mistake IMO. I have never seen wood deteriorate so fast. My buddy is a builder and he always says don't pressure wash anything wood, especially your siding (Vinyl for that matter as well) use a cleaning agent, a brush and the garden hose. Each to his own though.

[jeffk]

I have a 19 year old cedar topped dock and have tried cleaning it by scrubbing etc in the past. Last year I power washed it. What a dream. It took off mold, pine sap, everything and left it clean and ready to be restained. It came out far better than previous attempts. Was the wood raised a bit? Yes but not to the level of being a problem. I did not sand it. I used a solid color stain and did 2 coats. (The open wood is VERY thirsty) The staining process smoothed the wood down again. I was very happy with the results. Would I do this every couple years, probably not. But after many years of exposure it really brought it back to looking great.

Note: I did use the lower pressure nozzle. Duh. I have seen the high pressure nozzle etch concrete. Definitely NOT for wood.

[Orion]

Originally Posted by LIforrelaxin

Are you sure the boards you got where Pressure treated, and not just Thompsonized?

The Thompsonized wood doesn't hold up nearly was well as true pressure treated wood does.

Yep, it was pressure treated "NatureWood".

[windsail]

I want to thank everyone for the input. I started doing it my hand but it wasn't coming out very good and it's a large deck. We bought a small power washer, just enough pressure. Look like it is coming out great. letting it dry for a couple of days and will then stain and seal it. Has to be better then it was.

[Rusty]

Originally Posted by windsail

I want to thank everyone for the input. I started doing it my hand but it wasn't coming out very good and it's a large deck. We bought a small power washer, just enough pressure. Look like it is coming out great. letting it dry for a couple of days and will then stain and seal it. Has to be better then it was.

I'll bet it looks great. Thanks for sharing the results.