Photovoltaic Systems

The photograph above may not be what you would expect.  The outdoor bench in this detail is not made from an unsustainably harvested tropical hardwood.  The wood itself is actually maple, a widely available species that can be farmed and harvested without ripping up acres of rainforest.  But maple and many other similar woods are too susceptible to decay and rot when used unprotected outdoors.  The usual alternative has been treatment with chemical pressure treatment.  Now, through a method called kebonization, a Norwegian company, Kebony ASA, treats soft woods in a non-toxic process that allows readily available woods to be used for outdoor uses.

The process of kebonization is similar to pressure treating wood (which
is another way to make soft woods usable for exterior use). But,
instead of soaking the wood in toxic chemicals like chromated copper
arsenate (CCA, which is now banned for most uses in the US and the EU) or alkaline copper quaternary compounds (ACQ, the most widely used replacement for CCA after the ban), it is instead soaked in furfuryl alcohol,
a waste byproduct from sugar cane. There are no special handling
requirements or precautions needed to deal with waste from this wood,
and it can be disposed of just like any other untreated wood.

During the kebonization process, the alcohol becomes a resin that reinforces the cells of the wood. The result is a wood with excellent outdoor exposure tolerance like teak or mahogany, but with a harder surface than many of the tropical woods that it replaces. The wood also naturally fades to a silvery-grey color much like those tropical woods, as well. Maple is used in place of teak, and southern yellow pine is used in place of ipe.

Kebony wood can also be used for building siding. In fact, it is so water and weather resistant that it is even been used for building roofs and for boat decking (see below). The process also makes the wood less prone to swelling due to moisture. There is no necessity to paint Kebony wood, and it can withstand decades of exposure to the weather before any maintenance is necessary. According to the company, a kebony wood roof can last for 30 years before any maintenance is required.

Kebony wood is probably not going to do much for you in terms of obtaining LEED credits.  The material is imported from Europe.  There is no indication on the company’s website of the material being FSC certified wood, either.  Still, it is a natural wood product.  More importantly, it is a wood product that is durable without having toxic additives.  And it is obtained without clearcutting tropical rainforests.

Even more pictures are available on the Kebony website.

Photo credits: Kebony ASA.

As we noted here a few weeks ago, the draft for a new version of U.S. Green Building Council’s LEED (Leadership in Energy and Environmental Design) program was released for public comment and review.  In general, as a LEED Accredited Professional, what I saw in the program looked good.  The changes that are proposed will make improvements to the system.   Below is a discussion of changes we can look forward to in the next generation of LEED. 

LEED is not a single rating system, it is a family of rating systems.
When most people think of LEED, they are probably thinking of LEED-NC,
which is LEED for New Construction and Major Renovations.  But there
are also LEED-EB (Existing Building Operations), LEED-CS (Core and
Shell for multi-tenant buildings), LEED-CI (Commercial Interiors
build-outs), as well as specialist versions of LEED for schools,
hospitals, and more.  LEED-NC is the verion I am most familiar with and
the version I have reviewed here.  One goal for the reorganization of
LEED is to help harmonize the different ‘flavors’ of LEED to make it
easier for designers and builders to work within a consistent
framework.  This should be beneficial to the system throughout. 

The new LEED draft version is less drastic a change than I initially
expected it to be.  This is not a reinvention of the wheel, but a
refinement of how the credits are valued in order to increase the
emphasis on items which have greater beneficial impact.  The existing
credit items from LEED-NC 2.2 are all there, and there are basically no
new credits (though that’s not entirely true, and I’ll get into that a
bit later; it’s not as confusing as it sounds).  The final name of the
new system is also interesting.  Some documents refer to it as LEED
version 3, while others call it LEED 2009.  I think that, like the
building codes (which incorporate the year they were produced in their
title), USGBC is moving to use the year in the title, so henceforth, I
will refer to the new system as LEED 2009.

Reorganized Points System
The thresholds in
LEED 2009 are higher.  More points are needed to reach each level of
certification, as compared to LEED 2.2.  The number of available points
has risen from 69 under LEED 2.2 to 110 under LEED 2009.  Reaching LEED
Certified is now 40 points or more, Silver is 50 points, Gold is 60 and
Platinum is 80 points.  However, the total number of available points
is higher, and, significantly, a number of credits now gain multiple
points.

Most surprising were the Sustainable Sites credits for Development
Density & Community Connectivity (SSc2) and for Alternative
Transportation, Public Transportation Access (SSc4.1).  These are now
worth a combined 11 points, versus 2 points under LEED 2.2.  This
greatly increases the emphasis on urban projects, and building in
connected, accessible downtown makes a major step toward LEED
certification.

Water Use Reduction 20% is now a prerequisite for LEED.  A 20% water
use reduction used to get you a point under LEED 2.2 (and earlier).
This seems like an example where the industry has pushed far enough
along that what was innovative has now become standard.  Almost all
manufacturers are producing low-flow fixtures, and it is not difficult
at all to obtain this level of improvement.  So the point thresholds
are now 30% and 40% reductions (which are now worth two points
apiece). 

‘Extra Credit’
There is a new category of credits
available under the proposed system, but they are not new credits.
Rather, it is a bonus system, and four points for regional bonus
credits are also included in this additional category.  This allows for
the "regional authority" to designate targeted credits that are of
particular importance for a region, and, in effect, give double credit
for projects that meet those credits.  For an area where heat island
reduction was identified as an important goal, for example, it would be
possible to get two credits. 

Localization
Along with this, the USGBC is
trying to promote the activity of regions and individual chapters in
developing the system.  The regional bonus credits will be targeted by
zip code, although the USGBC is encouraging the regional groups not to
be too fine-grained in assigning different priorities to different
areas; that would make it difficult for architects, builders,
developers, and other professionals to be familiar with the
requirements.  However, it does allow prioritization for cities to be
different from the priorities for outlying areas.  Each group of zip
codes will have six local priorities identified, and up to four of
those can be selected, giving the project up to four additional points
for concentrating on areas the regional authority has indicated as
priorities.

A fifth point is available for Innovation & Design Process
(rather than four points previously) to promote more new ideas and
alternative methods for improving green buildings. 

Parting Thoughts
LEED is still far
from a perfect system, but no checklist is ever going to replace having
an intelligent and committed team, including the owner, designer and
builder, who all want to create a green building.  Those who expect
LEED to be a complete method to guarantee the creation of good, green
buildings will continue to be disappointed in what LEED is (and what it
omits).  Those who look at LEED as a tool that can help to push the
community forward in accepting and recognizing better buildings will
appreciate some of the improvements this new version incorporates.

Read other articles authored by Philip Proefrock.