Hello from Fargo Big-Al!!

Yes. House HAS to be pressure-washed with a good House cleaner. Make sure the tip is kept ONE FOOT away from the siding, and the pressure isn't TOO high!!
>>> You'll just wreck the shakes otherwise...

Now...
1) How old is existing paint?
2) How many earlier layers...are they Oil as well?
3) Because you're in the NE, I'm surprised you're considering Oil!! I'd avoid it like the plague...
4) ACE has discontinued most of its Oil paint production as of a YEAR ago! We've a few Exterior oils unsold for 2 years now...
5) Test for adhesion of your Oil coats. Make a LIGHT "X" cut into your paint-film, through to the substrate. Rub down a duct-tape onto the x and yank it off. Well-adhered paint won't budge. Old, brittle oil fims will often peel off. If old film is weak enough, curing Latex paints could literally "pull off" the old oil!!
6) Check some spots on your S & W sides, since they take the most beating.
7) Their must be a C2 dealer somewhere near you?!?! C2 has EXCELLENT Exterior paints!

(We're an ACE-Royal & C2 dealer...)

Faron

Faron, why would you avoid the oil base paint? The paint that is on there now is about 7-10 yrs old ( about 2 layers I think ). I will try that "X" test and see what happens.

Just wondering about why not oil base. If not oil base, what would you recommend . And thank you for the come back on all this.

Big Al

Power wash a shake sided house even from a foot away? What about all the water that gets behind the shakes into the frame construction?

Wow, this is a great site glad I found it!!! Can I use a latex paint over what I believe is a oil base paint??? I also believe that what is on there now was a solid stain...another question is there a way to tell WHAT kind of paint was used?

What I don't want to happen is to go thru the expense of out laying that money and finding out later that the new paint wont hold on the shakes.

Richardkittyhawk..what did you mean don't use O.V.T solid stain. What is that?

Thanks to All

Bigal

High pressure washing is never mandatory, ever. It depends on the job. There are several factors you need to look at. Is the wood dirty? Is it dirty enough that you need a power washer to get it clean? Often times you can dust the surface dirt away before painting or use a garden hose and a scrub brush. Is there a chance that water can get into the framing or even inside the house? If so, then it's just not worth it. If there is another method you can use to get the wood clean and ready for paint, then choose that method. Is there a chance that you can actually damage the home with high pressure cleaning or even blow some of the shakes off? Power washing is not one of those things that you need to do before every paint job. Filling wood with water is really the last thing you want to do before painting. Avoid it if you can.

BigAl

Is the oil based paint chalky? If it is chalky, it needs to be cleaned with Jomax or TSP, then allowed to dry, primed and painted. I do recommend using high pressure cleaning, but no more than 2500 psi. Use a fan tip and keep at least 1 to 2 feet away from the wood. Let it dry for several days before you prime and paint. This helps to clean the wood and force any loose paint off. It also removes any dirt and mildew that may be on the wood.

I would prime over the oil based paint with an oil based primer, then I would use a high quality latex paint for my topcoat.

Cabot O.V.T. Solid Stain is an older version of oil or latex solid stain. The Pro.V.T Latex Solid Stain is much better because it is thicker and covers much better. It is also more durable. It lasts about 8 years at the Outer Banks which is impressive considering the weather, salt air, wind, and sand, not to mention the hurricanes and northeasters we get so often. The Cabot Problem Solver Primer comes in either latex or oil and gives the stain a solid surface to adhere to. You could probably prime with latex primer, but I would use oil primer.

It is important that if you attempt to spray the paint or stain to backbrush or backroll the product to ensure adhesion.

There is a simple test for oil or latex product. Take a rag and some rubbing alcohol. Rub the alcohol on the finish with the rag. If the color comes off on the rag, it is a latex finish. If no color comes off on the rag, it is an oil based finish.