Home Building Articles
Net Zero Can Equal Net Gains
When it comes to a home's capacity to deal with moisture, air flow and heat, isn't high performance simply building better?
There are two routes home builders can take to try to engineer their homes to produce as much energy as they consume: one is through the envelope, the
other is through the systems.
And when you blend building materials that best deal with air flow, moisture, and heat with systems that capture, store, and generate energy, there's
just one way to make them behave—sustainably—as they should, and that's to build better.
Building a home better stands on four pillars, each of which must be true. First, it must have strength and durability to weather time and the elements.
Next, usefulness—it must perform well in its function as a complex of interoperable systems aimed at comfort, safety, air quality, and enjoyment.
Thirdly, a better home is more aesthetically pleasing in its orientation, its elevation, and its interior design. And last, it must feel more valuable
than it costs to buy and maintain.
If you're making homes better, they likely perform better when it comes to energy. From your slab, with, say, R-10 rigid foam installed at the slab
edge and interior of the stem wall, to the open-cell spray foam in the wall cavities and rigid foam on the exterior walls and roof deck, you create both
a continuous thermal blanket and a moisture and air barrier, with a drainage, and the elimination of possible penetrations. Unvented attics get sealed
and semi-conditioned; windows are double-pain, low-E coated, and argon-filled for higher performance water and air is better building, and it will save
energy and money.
Up to now, you've built better for how the home deals with air, moisture, and heat over a period of time. You've also, no doubt, solved for water
conservation and indoor air quality as ways of improving a home's usefulness to its residents. This work might earn a Home Energy Rating System score
of 50 or below, which puts it within striking distance of net zero energy once a renewable energy source—likely photovoltaics—is added to
the mix. Now,
added per square foot construction costs, with PV, may model in at just under $10, an amount most owners would recoup on energy savings within 10 years.
For home builders, the question has moved beyond whether potential home buyers want and are willing to pay for green homes. The question, rather, is can
you risk to not build homes better? The "road to zero," for most builders, is a road to building better, more valuably, and, one would hope, for net gains.