Are solar shingles worth it? An honest answer from a roofer

Solar shingles are a genuinely interesting product, and they are also the kind of product that attracts a lot of confident nonsense in both directions. We install them, and we install conventional solar panels, so we have no particular reason to push you toward either one.

Here is how the decision actually breaks down.

What a solar shingle is

A conventional solar installation puts panels on racking that is mounted through your existing roof. The roof stays a roof, and the panels sit above it.

A solar shingle is different in kind. The roofing material itself generates the power. GAF's Timberline Solar system, which is the one we install, lays down as part of the shingle field rather than sitting on top of it. You are not adding equipment to a roof. You are replacing part of the roof with something that also makes electricity.

The question that decides it: how old is your roof?

This is the whole thing, and it is why the honest answer is not a straight yes or no.

If your roof is near the end of its life, or has storm damage, or you are already committed to a replacement, then solar shingles are worth taking seriously. You were going to pay for a roof anyway. The incremental decision is between a roof and a roof that generates power, which is a much better comparison than the one people usually imagine.

If your roof is five years old and in good condition, the arithmetic is different and usually worse. Solar shingles would mean tearing off a perfectly good roof. Conventional panels let you leave it alone and add generation on top, and when the roof does eventually need replacing, the panels come off and go back on.

Where solar shingles genuinely win

• You are replacing the roof regardless, so the roofing cost is not additional
• You care what the house looks like, and racked panels are not what you want
• You would rather have one system and one installer than a roof and a separate array bolted through it
• You want to avoid penetrations through a brand new roof deck for racking

Where conventional panels win

• Your existing roof has years of life left in it
• You want the maximum generation the roof plane can physically support
• You expect to move before a roof replacement would come due

The part nobody can answer for you in advance

What either system saves you depends on your roof's orientation and pitch, how much shade it gets across the day and across the year, your household's actual consumption, and the terms available from your utility. Anyone who quotes you a payback period before looking at your roof is guessing.

We will not do that, and you should be wary of anyone who does. What we will do is come and look at the roof, tell you what the planes and the shading actually allow, and be straight with you about whether the roof is the right age for this conversation at all.

One thing that is true of both

Whatever generates the power, it is sitting on a roof, and the roof has to be sound underneath it. Putting either system over a roof with tired flashing or a valley that needs attention just means paying to take it off again later.

That is the one piece of advice we would give regardless of which product anyone ends up recommending. Sort the roof out first. Everything else is a decision you can make afterwards with better information.

What changes about maintaining the roof

This is the practical question people forget to ask, and it cuts both ways.

With racked panels, anything that needs doing to the roof underneath means the array has to come off and go back on. That is not a disaster, but it is a real cost attached to every future roof repair in that area, and it is a reason to make sure the roof is sound before the panels go up.

With solar shingles, there is no array to remove, because the generating surface is the roof. The tradeoff is that a repair in that section is a repair to a solar roofing product rather than to an ordinary shingle, so it is a specialist job rather than something any roofer can patch on a Tuesday.

Neither is a reason to choose one over the other on its own. It is a reason to think about who you will be calling in ten years, and whether they will still be around.

A note on the roof underneath either one

Flashing, valleys and penetrations are still where a roof fails, and adding generation does not change that. If anything it raises the stakes, because the cost of getting back to a bad detail has gone up.

So whichever direction you go, have the flashing and the valleys inspected properly first. It is the cheapest part of the whole project and the one most likely to cause trouble if it is skipped.

If you want a straight opinion on whether your roof is a candidate, call (210) 650-2090. Estimates are free, and if the answer is that you should leave your roof alone for another eight years, we will tell you that.