2 coats of Duration on new hardiplank is standard and it is what will give you the best outcome as well as protect your warranty.

I would not skimp on this...this is an investment that will last for years.

I can't answer your other questions, but I'm sure someone on this forum can/will.

I'm about to start a similar project on my house. I specified Duration paint TWO coats (all sides).

1. Do professional painters typically leave some unpainted spots on the undersides of the siding after just one coat, even a heavy coat?

No one can paint in one coat. No one. IMO, there is no acceptable circumstance where one coat of paint is a proper paint job -- especially exterior. And applying it *heavy* is meaningless. There is only so much you can apply on a vertical surface without it dripping and sagging. Then there's the classic debate of what is more efficient, one labor intensive *heavy* coat that pushes suggested application methods, or two comprenhsive full coats at the recommended and appropriate spread rate or thickness.

2. Am I being unreasonable in expecting my painter to touch up all the unpainted spots (there are a lot)?

I would say you each share equal blame on this one. You were being unreasonable to expect that exterior areas could be painted with one coat to save on budget. That is not a realistic expectation. He gets an equal amount of accountability 'cuz he told you he could do one coat and he accepted the job under those terms. You expected too much and he promised too much.

He tried to make it work within your budget. It just didn't work out due to certain circumstances. He shouldn't have to pony up all of the labor/paint at no cost to you to fix it. To be fair, you'll need to reach a compromise to correct an agreement that never should have been made.

3. Can Duration be easily touched up in spots, or will it have to be completely brushed on again to look good?

Maybe. Depends on the sheen and the color and the orientation the spots have to direct light. Depends on the expertise and method used to touch up. My guess is you should be doing a second coat because it sounds like there are so many spots, you're just about to a second coat any way. Besides that, it's the right thing to do for your house.

4. What should I be able to expect from my painter after two coats of paint in terms of COMPLETE coverage when I stand directly up against and under the siding?

Depends on the color. Depends on the exposure of light. Depends on the substrate, can depend on lots of things. Two full coats is standard to get to full and even color resolution and coverage - especially with Duration - but the standard isn't a guarantee. Painter should be able to call that one easily. One coat looks like crap, no one should be surpised including him. If he says two coats will do it, he should know what he's talking about, but he also said one coat would work. If he says one more coat will do it, you need to be clear that you aren't paying for the third if necessary and he can't walk away if he's wrong and after two it's still not right. Proceed with extremely clear and precise communication. If he's smart, he'll be after the same clarity of understanding from you for his behalf.

5. My painter says Duration is hard to work with and sets quickly in summer temperatures, which may be why his crew were unable to paint as completely as I would've expected. Do you professional painters feel it is hard to work with, or is my painter just making excuses?

Duration is harder to work with than say a Super Paint or a MoorGard. It is physically taxing i.e. the rotator area of the shoulder. You don't paint with Duration you *apply* it. It is different. Weather conditions could very well be adding to the efforts of application. Wouldn't ding him for his comments on working with Duration. Doubt that's an excuse. More like that's his commentary on how Duration fits with the painting skills and conditions he has to work with.

There's my third-party input FWIW.

How many coats are required really depends entirely on the condition of the current coating. If it's in good shape, and there isn't much of a color change, then there is a good chance that one coat can look good. Two coats guarantees a good finish though. Many painters will apply the first coat in a slipshod manner because they know a second coat is going to be applied to get all the misses. Is this right? Not really. IMO it would be totally reasonable for you to request that the undersides of all the boards be painted. It could very possibly be that the policy of the painting company is that the paint gets applied completely, yet some of the crew members are better painters than others. On some crews, speed is the name of the game. The faster painters get paid more per hour. Why are they fast? Because they don't paint everything!

Lottamoxie, Funcolors and Paintguy, thank you for your informative and thoughtful responses.

Given that I'm in New England, I guess it would be advisable for me to have the house painted with 2 coats on all sides, not just the front and back, regardless of whether my painter can make one coat look good. Sigh. I'm already 37% over budget on my whole-house remodel, so what's another ????

I think you have received some good advice. For more information, check out the forums on this website run by professional painters http://www.painterforum.com/

Here is a link that might be useful: http://www.painterforum.com/

Yes, you want 2 coats on all sides. It's imperative, IMHO. You don't want to have to have this job done again within the next, say, 15 yrs or so. Do it right the first time and save yourself a ton of headaches in the long run.

Is this siding on exterior of house? As a general rule we use a sprayer and give 2 solid coats on the side facing outward.... I've never seen painters attempt to paint the underside... You may be seeing spots of underspray... On carpentry jobs we replace a lot of hardi board siding... Due to rot and mildew... Contrary to the ads about its longevity... It's honestly not great to work with... I would highly recommend buying vinyl that doesn't need to be painted... Or real wood. Hardy board is basically cheap particle board with a very small amount of cement added... It is brittle... Breaks easy... And painters aren't really trained to remove it to paint the underside without it breaking

Or... Painters could spray before the install if it's that big of a concern... I usually remove the old hardy board... Replace it with new... While replacing any real wood... Like window frames etc... Then paint it all with a sprayer in 2 coats as the very last finishing touch... No customer ever mentioned the underside of this in my experience