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Wednesday, December 30, 2009

Windows and Doors

Windows are a critical element of the dwelling envelope providing function as well as form. With a passive solar design emphasis, window placement, size, glazing and function (ventilation?) are important considerations. The materials used and their source, fabrication and product performance criteria are also considerations. Windows are expensive particularly in the high end market and they tend to be the first target of cost cutting when it comes time to sharpen the pencil.

We still regret the choice we made with our first house so we decided that we would place a premium on windows with this project. Successful engagement in a project like this requires curiosity and a desire to become fully informed about all things pertaining to the project, including windows and doors. Detail like this can be boring but illuminating at the same time. Like sentence diagramming but discovering dangling participals or vice versa, depending on your spatial reasoning. Sister Slaughter must still be disappointed; Mon still doesn't know I received a D in 8th grade English.

During the design phase we decided to use Loewen as the product of choice. They received the most awards for quality and was recommended by our architect. http://www.loewen.com/home.nsf/index Loewen's environmental stewardship also appealed to our values; Loewen was the first major North American window and door manufacturer to receive FSC chain of custody certification. Knowing where something came from and under what circumstances is important to us.

FSC is the Forest Stewardship Council, an independent, 3rd party non-profit organization that promotes principles for sustainable forest management. Here is a link that provides detail on their 10 principles and 57 criteria for forest management. http://www.fscus.org/standards_criteria/ Our decision to go with Loewen allowed the architect to incorporate Loewen's window and door specifications and sizing into the drawings so rough opening measurements and exact locations are shown in the drawings.

Casement windows are the most energy efficient operable windows and they were our choice from an aesthetic view as well. Loewen provides the highest quality windows available using Douglas fir wood, stainless steel hinges and extruded aluminum clad exterior with advanced Kynar coating (fluoropolymer resin). Loewen's craftsmanship is superb. These are really good windows and they cost beau coup bucks!

All the windows facing south will not have the low e coating that reduces light pass-through so we can optimize solar gain in cold months. The concrete floor functions as a heat-sink which means it captures the heat from the light pass-through and stores it. The captured heat slowly dissipates throughout the day, helping to provide warmth. All the windows facing east, north and west have low e glazing to reduce solar gain in the warm months.

A better understanding of what is meant by "passive solar" will be helpful in appreciating some of these small but important window features. In broad terms, passive solar for this project means that during the cold months when the sun is low in the sky, sun light is able to pass through the windows to the heat-sink to later dissipate heat through the day. During the warm months, the leaf canopy of the deciduous trees and the roof overhang provide shade from the sun to minimize heat gain. We'll tell you about our living roof later!

So, the dwelling must be oriented to true south to take advantage of this solar benefit. In our case, the tree canopy in the summer was a factor as well as window placement and roof overhang. Sigi spent a fair amount of time working these design elements, calculating the optimum location and footprint orientation.

Its the job of the builder and surveyor to plot the location and orientation on the ground from the drawings. Later, we'll talk more about ventilation, light and window view considerations in regard to window placement. Another item on our agenda is the selection of stone for the fireplace. Windows and doors and the fireplace stone selections need to be made now so the project's progress will not be delayed. We are working with multiple time schedules and sequences so planning is key.

Sunday, December 27, 2009

Survey, Footings and Foundation

Now that the lot has been cleared and graded it is ready to be surveyed so all the dimensions and angles of the structure's footprint are to scale and oriented per the specifications of the plan. The footings are the base upon which the foundation rests so precision in this step is important. Normally, poured concrete is the material of choice for footings in traditional construction methods but our footings are dry rubble.

Concrete is expensive and has a high energy component due to the electricity needed to generate the high temperatures used in processing limestone into Portland cement, a key ingredient of concrete. Believe it or not, concrete production accounts for 5% of the world's CO2 emissions. Here is a link to an interesting and informative article about concrete that references the construction of the replacement bridge in Minneapolis MN for the one that suddenly and catastrophically collapsed in 2007.
http://www.nytimes.com/2009/03/31/science/earth/31conc.html

We chose to go with the architect's recommendation of using dry rubble footings. She had experience with dry rubble footings and is a proponent of reintroducing this old but green construction technique and John, our builder, was open to the idea and went with it. Here is a link that explains dry rubble footings.
http;//www.buildnaturally.com/EDucate/Articles/RubbleTrench.htm

You will see as we progress through this project that many decisions were made in the planning phase but there will be more to come, with most involving some degree of a sustainability trade off if our experience to date tells us anything. We had numerous conversations with the architect about sustainability and how to find balance amid the conflict of interest that invariably arises. The most common conflict is cost vs. benefit. Benefit comes in degrees from green, to greener, to greenest.

Cost is a straight forward concept for most people to understand but less so in the context of time. In financial matters it comes down to rate of return, compounding etc. When you incorporate architecture, utility and all the intangibles associated with a sustainable dwelling, you have a lot more factors to consider than simple math. Sustainable dwellings that function efficiently yields the best possible value, over time in addition to being a nice place to live and healthy for you..

In contrast, residential home ownership in the US is on average less than 5 years in duration and the construction industry has not lost sight of this fact notwithstanding building codes and inspections. Materials, workmanship and sustainability have been lagging for so long that its absence is the norm. We believe the cost of energy and water will progress to the point where efficiency will drive everything. It has been predicted by some that today's McMansions will be tomorrows eco slums; another housing disaster waiting to happen or the possible retrofit of the century. Okay, back to our project.

After the footings were excavated, filled and compacted, the builder constructed wood forms above the footings to hold the poured concrete used to make bond beams that outline the footprint of the structure. This concrete framework will carry the walls and structural components of the dwelling while providing boundaries for the concrete slab or floor to be poured at a later date.

Because the structure spans a good length of grade change, numerous elevations are needed to keep the structure level. On the back end of the footprint facing west, concrete block is used to provide a frame to hold the back fill used to occupy the void created by the elevation changes used to flatten grade slope. The structure, wanting to be level and our desire to keep interior elevations to a minimum added complexity to the structure.

The specifications for the bond beams, due to load, span and footing design, require considerable steel reinforcing. John was meticulous in making sure the required rebar sizes were used and set properly to accept the concrete pour. Our plans called for heavier (stronger rebar) to be used to maintain structural integrity for the long term.

Next, the surveyor provided the exact measurements and precise locations for the block to be laid for the foundation. The use of a chalk line that is held firmly and snapped leaving a neat chalk line is used by the bricklayer as a guide to lay the block. My brothers and I learned the trade of bricklaying from our father (he wanted us to lean a trade, always to be assured of having a means to earn a living) so the significance of the terms plumb, level and straight didn't go unnoticed in my observation of the finished masonry presented by Dave the mason with participation by John our builder (a bricklayer by trade).



Saturday, December 5, 2009

The Concept and Beginnings

The purpose of this blog is threefold, provide a record of the project's progress for friends and family, share information about the project that may be useful to others who may be planning to undertake a project similar in concept and to help promote a better understanding of sustainability. Critiques, suggestions and comments are welcome.

To begin with, Shady Grove is the name for the project. Broomgrass is the name of the community where Shady Grove is being developed. Broomgrass is a 320 acre 19th century organic farm that is the basis for an alternative community development sensitive to the environment. Broomgrass is comprised of 16 one acre lots with the balance of the community owned land in a farm preservation trust. It is located in the panhandle of West Virginia in Berkley County near Martinsburg. http://www.broomgrass.com

We acquired our lot in September 2005. Our first task was to begin the process of finding an architect that would be a good fit with our philosophy and approach to the project and the end result. Finding an architect that is a good fit is the single most important step in the entire process. Wendy and I feel that we are tuned-in, creative and able to express and articulate our needs and dislikes so having an architect with the same sensibilities as an equal partner in the process was paramount.

I stumbled on an HGTV show that featured a strawbale dwelling designed by Sigi Koko. I googled her website at http://www.buildnaturally.com and contacted her to see if she was interested in hearing about our ideas. Wendy and I had an exploratory meeting with her to discuss the project at the conclusion of which we decided not to consider meeting with any other architects provided that Sigi accepted the project, which she did.

We began work with Sigi in September of 2006 and completed the planning phase of the project when permit ready plans were completed in June 2008. Yea, now what? Will it cost what we think it will and who will we get to build it? But life is full of interruptions...

We took a break from the project due to the economic meltdown in the fall of 2008; uncertain times dictated that we take a patient and cautious approach with the next step. We just hunkered down like most people, avoiding unnecessary risk and hoping not to be an unfortunate casualty like so many others. By August 2009 we felt the worst was over; we decided it was time to come out of our shell and move forward with the project.

The next step was to find a general contractor to construct the dwelling with the same high standard of craftsmanship, sense of aesthetic and importance of sustainability as ourselves and the architect. We decided to work with John in May 2009 anticipating a start sometime in the fall of 2009. The construction phase of the project got underway when the county building permit was issued in September 2009.

During the period of delay between the planning phase and construction phase we undertook some pre-construction activities in anticipation of some day moving forward with the project in earnest. We conducted a tree survey of the wooded lot to maximize the dwelling location and orientation for passive solar, grade slope, view and aesthetic while minimizing tree removal and ground disturbance detailed in the plans. All of this was calculated by the architect and included in the drawings because it is integral to the entire project.

We obtained the services of a forester/surveyor and conducted the tree survey by locating the position of all trees by species and variety that were 10" in diameter at 4' height. The next step was to obtain the services of a land clearing contractor to clear the wooded area for the footprint and orientation of the dwelling per the the plan specifications. The idea of clearing the lot raised some questions about how exactly the process works!

We then obtained the services of a local land clearing contractor with the experience and equipment to do the job. Using local tradesmen is one of the objectives of sustainable building and supports the local community. The approach to clearing is simply but methodically bulldozing over the trees to be removed. As part of the sustainable approach to the project, we anticipated the extraction of usable lumber from the standing trees.

Our architect suggested bringing a lumber mill to the site called a portable site mill to saw the logs. With this in mind, an experienced land clearing contractor goes a long way due to the risk of damage knocking down very large trees. As a tree is knocked down it wants to fall in a certain direction and takes everything in its path with it including limbs of other trees as well as whole trees. We wanted to minimize damage to the trees that would remain as well as those that had potential for lumber.

The diesel Case 1155E was roaring and John the operator with a prosthetic arm and hook (his arm was severed by the hydraulic compressor of a garbage truck when he was a young man; he said he swore he would never wear gloves again using heavy equipment) maneuvered the bulldozer as deftly as a kid playing with a Tonka toy. He was very knowledgeable about the species of each tree, its characteristics and its desire to fall in a certain direction based on any angle of lean, the grade slop, root crown, canopy size and shape and soil type and condition, all of which he knew intimately.

The fallen trees then had their limbs and exposed stump sawed off with chain saws by the crew in one area while the operator knocked down others. The logs were moved and staged for the portable site mill to saw them to the specifications of the lumber schedule. As with most construction activities you have to anticipate what is needed after each stage so the process moves along efficiently. I remember a saying I learned a long time ago which has served me well if remembered at the time, "most people don't have time to do it right but always find the time to do it twice".

A lumber schedule was developed by the architect to guide the site mill operator in extracting as much usable lumber from the fallen trees for use in the project as possible. With the assistance of the forester, we identified the following tree species and varieties for use: red oak, scarlet oak, black oak, white oak, chestnut oak, hickory, black walnut, Virginia pine and Table Mountain pine. Limbs and trunks that were not usable for construction lumber were sawed to 18" for use as fire wood and staged for splitting.

Seeing the site mill in operation was very interesting to say the least but seeing it arrive as a trailer pulled behind a pickup truck and unfolded like a mechanical creature like in the movie "Transformers" (I have only seen the movie trailer on TV) was impressive. The instant transformation of these huge trees of at least 80 years or more in age in a matter of minutes into 15' long 12"x 3" boards, was amazing.

The next step was to stack the lumber for air drying or curing and to protect it from the elements. I took on this task by erecting a wood and bamboo frame covered with a tarp that was tied down to withstand the elements (gale force winds and the like or so I thought). My brother Brendan suggested that the ends of the boards get a coat of paint. This would prevent or reduce the boards from cracking and checking due to different rates of drying on the ends of the boards during the natural seasoning process.

We used an old can of house paint one day to paint the ends of the boards as suggested. It was a beautiful summer day with an incredible sky of clouds. While I was painting Wallace and Avery played frisbee in the field and Wendy was taking some photographs of the clouds. She used the images she captured for a reference to do a drawing titled "High Clouds Over Broomgrass" that was awarded "best in show" at The Art League located in the Torpedo Factory in Alexandria VA.