Don’t believe the scary scenarios about future climate change, habitat loss, and disappearing resources so prevalent in the media these days? Well, it’s true that in averaging out the ups and downs of ice ages and tropical eras, the world has stayed pretty much the same when you crunch the numbers over the eons that it’s been around.

Unfortunately, we may or may not be around for the eon when things start ­cooling down again.

But whether or not you’re skeptical about the forecasts, the world has been changing, and I could list the changes that scientists say have already occurred—­carbon dioxide levels in the atmosphere have increased by nearly 37 percent since the beginning of the industrial revolution; average global temperatures have risen by more than a degree in the last 100 years, with more than 75 percent of that increase taking place in the last 30 years; the Arctic Ocean has lost 23 percent of its permanent ice cover since 2005; polar bears are in ­danger of becoming extinct, to name a few.

I could also remind you of the price of oil—as if you could forget—as a reason to build homes that are more sustainable.

But I think you’ve heard all this already.

So if you’re not yet on the sustainability bandwagon, what’s it going to take?

Maybe you could be persuaded by a builder I spoke with recently who’s been building green for about 10 years. He told me what a lot of other builders have said, that he didn’t go into it for philosophical reasons; he wasn’t a tree-hugger or afraid of global warming. He just wanted to build better houses, ones that utilized passive cooling principles, for example, instead of larger HVAC systems. He fought an uphill battle through the boom trying to sell his houses, though. Buyers were more interested in getting the most house for the money, period. But now, buyers are looking for the best deal possible, not just in the sales price, but also in what the house is going to cost them on an ongoing basis. So, just like many other “overnight sensations” who work in the trenches for years but suddenly come into sharp focus in the public eye, his company’s homes now look cutting edge. His customers, and he has plenty of them, say in after-purchase surveys that they bought their homes because of the green aspects or because of their inherent energy efficiency. Not content to rest on his laurels, this builder intends to forge ahead, aiming for zero-energy homes, believing still in continuing to pursue his goal of building better houses.

But if you’re just getting into this, you don’t have to start with zero-energy homes. Those already building green say there can be a pretty steep learning curve at the ­beginning for both the builder and the subs. So start small. In fact, building smaller homes would be the perfect place to start. Plenty of boomers are looking to downsize, and young families need smaller, more affordable places to buy. If you’re building closer in (an important part of sustainability and, coincidentally, where everyone wants to be right now), smaller homes make more sense. Living closer in means shorter car trips for work and errands. Lower costs for materials and less waste to haul to the dump are other benefits of building green.

Even the smallest of changes can reap big rewards. According to the EPA and the Department of Energy, “If every American home replaced just one light bulb with an Energy Star–qualified bulb, we would save enough energy to light more than 3 million homes for a year, more than $600 million in annual energy costs, and prevent greenhouse gases equivalent to the emissions of more than 800,000 cars.”

That’s a very big result from a very small change.

As a home builder, you are in the enviable position of being able to effect significant change on whether or not your customers will be able to afford their heating andcooling bills, on your community, and even the planet—simply by making small changes in the way you build.

If you haven’t started building sustainably, it’s time you did. The rewards will be enormous.