Cohousing-L Mailing List: Re: Cost of Green Building

[Philip Proefrock (architect]

> Can any of you suggest good websites that might give ball park figures for
> how much various components of green building possibilities would cost?
> If that component would save energy or resources, how long it would take
> to pay yourself back through energy or resources saved?

I went to a LEED Technical Review last week, and this issue was something
that was discussed in the program.  In a study of a number of LEED
certified projects, they found that there was an average cost premium for
green construction of only a couple of percent (and there are some cases
where green construction actually saved money).  Even LEED Platinum was
only an average of 5% more expensive than conventional construction.

They had a graphic showing building costs for a range of buildings of
different types, comparing green (LEED certified or better) and non-green
buildings.  (These were presented as cost-per-square-foot.)  The
distribution was the same.  Different projects had different costs, but
there was not a clustering of green projects at one end or the other.

Many green choices are not necessarily apples-to-apples comparisons.  A
metal roof is going to be more expensive to install than a shingle roof,
and a vegetated roof is likely going to be even more expensive.  But the
shingle roof will need to be torn off and replaced (which creates dumpster
loads of construction waste and has real costs for both replacement
materials and for the labor to tear off and re-roof) much sooner than
either of the others.  And there may also be energy cost differences
between having a vegetated roof and having a traditional roof.  Some of
the benefits of your roofing choice will have effects on other parts of
the building (both positive and negative).  The vegetated roof will likely
last the longest, but it may require more structure to support it than a
conventional roof.

And many times, the tradeoffs are not cut-and-dried cases where one option
is clearly preferable.  You can improve the indoor air quality and comfort
of a building by providing operable windows and individual control for
heating and cooling.  But you lose some measure of energy efficiency from
that.  So you need to find the balance between the two that works the best
for you (and that balance will not be the same for everyone; there's no
magic formula for any of this).

There is a lot of synergy in green building.  Choices in one area can have
benefits in a number of other parts of the building.  And some of the
benefits are in the operation of the building, rather than in its
construction cost.  It's tempting to cut corners and try to lower
construction costs, but if you focus too much on the installed cost, you
can end up hurting yourself in the long run.

My point is that this isn't something that is an easy, pick either A or B
kind of decision.  There are tradeoffs in all of this.  Try to take as
long term a view as you can (both in the sourcing of the material and the
life-cycle costs of owning it).  Think about the maintenance that various
choices will require, and address those costs (whether they are monetary
costs or community labor costs) in your considerations.

Best Regards,

Philip Proefrock