Is there an easy way to estimate the additional cost of green vs. standard building? First, no--there is no "magic calculator"; building projects are too complex and unique to apply a simple template that can be universally applied.

But more importantly, the entire premise of this question is misleading. Going green can actually cost less. First, let’s clarify the term “cost” so you can compare products and technologies appropriately. Which costs more: a $.75 incandescent light bulb or a $3 compact fluorescent? If you pay $.75 for an incandescent bulb that has a one-year lifespan and costs $10 to operate over that year, the annualized cost is $10.75. If instead you buy a $3 compact fluorescent that has a ten-year lifespan and costs $3 to operate each year, the annualized cost is just $3.30—70% less than the product that appeared to be such a steal at first glance! Think long-term, or lifecycle, cost rather than what you're paying today. And remember, cost is not synonymous with value. How much more would you pay for a gallon of paint that you knew wouldn't emit harmful chemicals in your child's bedroom?

When it comes to housing, the cost to build any project, green or not, depends on numerous factors. Costs can basically be broken down into five categories:

Advanced framing, sometimes called Optimal Value Engineering, is basically a building method that reduces lumber use, minimizes wood waste, and maximizes a structure’s energy efficiency. For every piece of unneeded lumber eliminated, a builder saves three times: once by not purchasing, once by not moving around, and once by not hauling to the recycler. And eliminating unnecessary wood allows more space for insulation—making your home more energy efficient and saving you money in the long run. And of course, smart wood use also saves trees and forests.

Advanced framing is a collection of techniques that are allowed by building codes. It better integrates the design, engineering, and construction trades—as these trades tend to pretty much work independently. Given that advanced framing saves resources and energy, it’s an excellent green/sustainable approach to construction and is considered ‘better’ than standard building methods. Sounds like a good idea, so why isn’t it used all the time? Sadly, advanced framing can be challenging to implement because of added design and coordination requirements. For advanced framing projects, the project manager needs to:

There’s never been a better time to invest in energy-efficiency improvements for your home and in turn support the “green economy” and larger movement to reduce our dependence on non-renewable fuel resources. Gas and electricity costs continue to escalate, homes continue to be drafty and uncomfortable, and lots of incentives are available to help reduce upfront costs of upgrades!

To make the best use of your dollars, spend them in this order:

1. Reduce energy demand,
   
2. Optimize energy use, and finally
   
3. Incorporate renewable energy.
   

It wouldn’t be smart to install a solar water heating system, for example, before first reducing demand for hot water by installing low-flow showerheads and water-efficient appliances. The Federal Energy Policy Act of 2005 was just amended in February and generously boosts tax credits for homeowners:

Start by taking advantage of tax breaks for improving your home’s shell (exterior envelope) by reducing air leakage and heat loss between your heated interior space and unconditioned attic. For best results hire a home-performance contractor that verifies their improvements with testing equipment. The first step should be to apply caulk or spray foam to cracks or gaps in the attic floor. Don’t allow this step to be skipped—air leakage likely accounts for over 25% of your home’s heat loss!

If ductwork runs through the attic, ensure it’s not crushed or damaged and runs as straight as possible and then seal joints with mastic. Next install blown-in cellulose attic insulation to provide minimum R-30 (a measure of resistance to heat flow,) an 8- or 9-inch depth—though if space allows a full 12 inches is even better. Bury ductwork in the insulation if possible.