Looking for some general advice on new construction of a small (1200 sq ft) house in zone 5 seacoast NH. We are anticipating putting solar panels on the roof. Are there any special features on the roof build that will make it easier to incorporate the solar panels. Assuming it's not practical to predict power use but we do want a very insulated, efficient design, mini splits heating , hrv, and energy star rated appliances.

I'd think about what happens when it's time to replace shingles (if that's what you are using). And of course slope and direction.

we want to go with a metal roof, possibly raised seam. the house is on a gentle sloping south facing slope. we have a similar roof on our current house, the snow generally avalanches off in 2 or 3 days.

It would be better if you get a solar consultation because every solar power project starts with a quick conversation to see if solar is right for you. Solar panel systems installation takes one single day.

Standing seam metal roofs are easy to install solar panels on without having to penetrate the roof.

Posted By ICFHybrid on 24 Feb 2016 08:22 AM
Standing seam metal roofs are easy to install solar panels on without having to penetrate the roof.

Without penetrating the roof? That's interesting, how does that work?

The panel mounting structure essentially clamps to the standing seams.

Interesting, I hadn't thought of that,

Thanks

Be sure to allow for the additional ~3-6 lbs per square foot of roof loading in the truss or rafter design, and have it spelled out in the design documentation.

Retrofit structural upgrades or even retrofit load analysis is far more expensive than having it all squared away before the thing is even built.

Run through the "3 Renewable Energy Ready Home Infrastructure: Solar Photovoltaics" checklist on page 2 of this document:

https://www1.eere.energy.gov/buildings/residential/pdfs/rerh_pv_guide.pdf

Here is what we did
Standing seam roof
9/12 roof - Although I've read 8/12 is slightly better for production for fixed panels for our latitude.
South facing roof
Nothing on the south face of the roof except the roof (no vents, no chimney etc).
Conduit running from attic to the basement (or wherever the electrical panel is).

I was surprised that a breaker wasn't used for the solar panels backfeeding, so apparently a 240v breaker slot in your panel is not a requirement. 

Before anything you need to determine the best placement for the solar panels to make sure it had good solar exposure and don‘t fall into shadows too much. You technically can mount on your roof, but honestly if your house is small, the number of panels that you need to practically power your house is too many for the roof. Cleaning your panels is pretty important because you loose efficiency as residue (bird poop) builds up. Also as I learned just a few days ago, when it snows, you need to clear your panels. Cleaning becomes super simple and a lot safer when you don’t have to climb onto a roof via a ladder. Therfore I suggest you to install them on the ground.