On Thursday, Tesla hosted a “Special Meeting of Shareholders” to discuss its pending SolarCity acquisition. The shareholders voted overwhelmingly in favor of the merger, which no doubt delighted CEO Elon Musk (even though he knew it would work out). During the post-vote question-and-answer period, Musk said that Tesla expected its solar roofs to cost “less than a normal roof.”

“Honestly, in looking at this, it’s like I don’t know why anyone’s not doing it — it’s not that crazy hard, so beats me.” Musk said. “It’s looking quite promising that a solar roof will actually cost less than a normal roof, before you even take the cost of electricity into account,” he said.

He explained the roll-out plan. Next summer, Musk said, Tesla will release the first variant of its impressive, camouflaged solar panels. In the end, there will be “four main types… and [Tesla will] roll them out one at a time.” The first version will be the most popular, in-demand version, and then Tesla will release the other three versions “on three month cycles.”

Elon during Thursday's post-vote Q&A session. Tesla

The cost, he said, will depend on a few factors: The size of the house, the difficulty of installation, and so on. But in general, according to Musk, it will be at least equal, if not “slightly below the cost of a regular roof. The electricity is an added bonus,” he said. That means you’ll save money on the initial investment (no doubt aided by state and federal solar incentives), and then you’ll continue to save money on electricity as your fancy new solar roof collects energy.

One would expect the opposite from a high-tech, designer-grade solar roof. Musk explained, though, that the “roofing supply chain is extremely inefficient… Roofing just hasn’t gotten a lot of love.” Musk, with Tesla, is to give roofing that love. The big inefficiency is transportation, if we’re taking Musk at his word: Traditional ceramic and concrete tiles, used for some roofs, are very heavy and tend to break. Tesla Glass, however, is lightweight — “The glass weighs maybe a third to a quarter, sometimes maybe as much as a fifth as much as regular ceramic and concrete tiles,” he said — and extremely durable. Tesla, unlike these dated companies, doesn’t have to spend much on careful, costly transportation to ensure that the heavy tiles remain undamaged.

“Just by cleaning [the supply chain] up, there are huge gains,” Musk explained.

Shareholders, by now, are probably getting pretty sick of the discussion — but, after tonight, it’s been at last put to rest. Shareholders overwhelmingly decided to approve the proposal, so Tesla and SolarCity will indeed meld into one alternative energy megalith.