The Good Wood

Canada and the U.S. are unique among most developed nations in their extensive use of wood framing for home construction.  The use of that extensive and renewable resource pays multiple dividends.

Growing trees absorb greenhouse gas released by fossil fuels, but dead or burning wood releases carbon dioxide.  About half the dry weight of a tree is carbon, so the sustained harvesting and processing of mature trees sequesters carbon as finished wood products for home construction.  Carbon dioxide gas emitted in wood processing is offset by the carbon dioxide gas take up by replacement trees as they grow. 

 Wood framing provides for a better insulated wall cavity than steel studs, and steel studs consume eight times more energy in their manufacture.

Here in the Northwest, we are blessed with renewable supplies of Douglas fir for framing, doors, windows and trim, poplar for interior trim, cedar for siding and exterior trim, and hardwoods such as oak, maple, cherry, and walnut, for cabinets and flooring.  Reliance on locally sourced materials minimizes pollution by limiting energy consumed by transportation.

Some of the woods that might be selected for cabinets, decking, and other finish applications may not be harvested in the Northwest.  A favored choice for decking, Ipe, also known as Ironwood, is a type of Brazilian walnut that lasts for decades without the use of chemical preservatives (1).  This material is so dense, it must be drilled and screwed in place, because you can’t drive a nail through it.  However, according to www.rainforestrelief.org , there are serious issues with the harvesting of Ipe:

“Ipê, like many other trees in the tropical rainforests, only occurs in densities of one or two individual trees per acre in most of its natural range. To meet the orders for hundreds of thousands of board feet of FAS (“fine and select” or “four-side-clear” — meaning no knots or defects on all four sides of the board for its entire length), loggers have to log thousands of trees. That means bulldozing roads and skid trails into thousands of mostly pristine acres of old growth rainforests as well as damaging or destroying up to 28 trees for every one they target. The canopy is reduced by about 50% after loggers take the mahogany, ipê, jatoba and a few other high-value species for export.” 

Mahogany has long been a popular choice for doors and cabinets, and jatoba makes a beautiful hardwood floor.  When an imported wood is used, the best sources are sustainably-harvested woods, such as plantation-grown mahogany, or wood that has been certified by the Forest Services Council (2). 

 

All of the woods used in this Mercer Island remodel were harvested in the Northwest.  The exposed ceiling rafters are fir, and part of the original house construction, stained to match a new cedar ceiling above the rafters.  Cabinets and flooring are rift-cut oak, and exterior doors are vertical grain Douglas fir.

High quality wood can also be reclaimed from existing homes.  The framing lumber in older homes is often superior to what is commonly available today.  Removing individual posts, beams, studs, etc. is a painstaking process, and the labor cost can offset savings on materials, so this is an environmental choice and might not be an economical one.  Cedar siding can be carefully removed, and sometimes flipped to expose the non-weathered side, or simply refinished with stain or paint.   Tongue and groove cedar ceilings and wall paneling were common interior design elements from Northwest contemporary homes, and we have been able to salvage and re-use that material in past projects.  It is also easy to match with new material, providing that a stain is applied to blend old and new together. 

The ceiling and floors of Lane’s house on Queen Anne are made from reclaimed Douglas fir, taken from Roosevelt High School in Seattle when it was replaced in 2004.  Floor to ceiling doors in the dining room are Alaskan Yellow Cedar, made from trees felled 80 years ago and recently recovered from the bottom of a river. 

The same is true for many types of wood flooring, but it can be a serious challenge to pull up tongue and groove boards that have been nailed through the tongue, as the wood tends to split apart.  

This Old House, Recycled

We’ve created new homes by building on existing foundations, reusing existing framing (whole walls and floors or recycled materials), and saving original brick, stone and cedar siding. Pre-WWII foundations often lack sufficient steel reinforcement to meet today’s seismic (earthquake) standards, but some of them are adequate and many brick homes from the 50’s and 60’s have particularly strong foundations capable of supporting a new second story. Old growth framing lumber found in older homes is often superior to what we can find today. Old growth cedar, used as siding on many existing homes, might have 60 or 80 growth rings per inch, compared to fewer than 10 per inch in new growth cedar, resulting in greater strength and rot resistance. Old brick can be removed, cleaned and reused, and in many cases can simply be left in place.

(image: used brick detail of 2235 First Avenue North residence designed by Coop 15)

If an existing house is going to be replaced, or extensively remodeled, the first step is to have it stripped of any re-useable materials. Non-profit organizations such as the Re-Store (http://www.re-store.org/) will remove unwanted windows, doors, cabinets, lights, plumbing fixtures, banisters, etc. if they think they can sell them, reducing the material that might otherwise become landfill, and you will receive a tax deduction in the process.

Where contractors once hired demolition companies to remove the remainder of the structure with a backhoe and dump truck, some builders are now “deconstructing” most of the house in order to sort and recycle as much of the debris as possible.

(image: Re-Store.org)

Law Office and Home

These are the latest renderings of our designs for a live/work remodel and addition in the lower Queen Anne neighborhood of Seattle. The majority of the original structure (dating back to the 1920's and remodeled in the 1970's) will be saved, and the original foot print will be slightly reduced by shrinking the exterior decks, making way for new planting beds. The roof deck will be engineered to support plants, too. The old windows and doors will be replaced with energy efficient units, and the heating and ventilation system will also be upgraded to a high efficiency system. The siding is in extremely poor condition and will be replaced with fiber-reinforced cement products, while new decking will be made from recyled plastics. But what makes this home truly "green" is that it contains just 1200 square feet of living space for the two owners, plus a ground floor office that results in a zero commute for the owner.