Ari van Schilfgaarde
Environmental Studies Internship
Internship Final Report

Sustainable Housing Construction in Walla Walla


Walla Walla is growing; people have “discovered” this little town and are flocking to it. Walla Walla’s growth is a great asset to the town economically, but if the increase in housing is not sustainable, the very reasons people are coming here will disappear, leaving Walla Walla for the next great Western town, and leaving it to face the economic rut of a shrinking population. This internship focused on working with the Northwest Renewable Energy Festival (NWREF) and local builders to find blocks to sustainable development and find economically viable alternatives to the standard housing model. I created a pamphlet discussing my findings along with payback statistics and feasibility of using sustainable products for builders and designers to give to their clients in the area. While I mostly focused on new construction, some of the solutions that I found can be used in retrofitting older buildings.

This internship was largely self-directed and self-motivated. I worked individually to do much of the research, and I spoke to the builders on my own. I got a lot of support from Karen Yager, who put me into contact with the people I needed to meet and checked in with me periodically. Her recommendations proved extremely valuable both in my interviews and my research directions.

This was a good internship for me because it allowed me to work in a field that I am interested in (perhaps professionally) and to gain real world experience about problems and solutions that people face in daily decisions about their houses. The best part of the internship has been the possibility to create a network of people in a field that interests me.



My goals for the internship were to help to describe and address the constraints the construction industry faces when trying to build fully sustainable housing. The housing code currently mandates energy efficiency far beyond the requirements of even ten years ago, but it is still far from truly sustainable.

I also wanted to put together a pamphlet to address some of the issues that I noticed were common responses to my questions. In researching the answers that I received by builders, I hoped to come up with some solutions and recommendations for providing interested builders (and their clients) the tools to build a more sustainable community in Walla Walla.

My personal goals for this internship were to better understand the reasons that people choose not to utilize sustainable options. I was under the impression that it was mostly a lack of education and interest. I did not think sustainable development was necessarily blocked or hindered solely by economic concerns. As a student interested in land development and civil engineering generally, I wanted to deepen my understanding of design processes with a specific emphasis on sustainable design. Ideally, I would have worked with an individual builder on a construction project, but the general information that I have gathered throughout this process will help me with future collaborations.


Experiences and Conclusions:

I divided this internship into two main components. First, I developed an interview with builders in the Walla Walla area and did research about the general trends in the area. I met with three builders here, Joe Petrello, Dirk Nelson and Mike Eytchison. Mr. Eytchison is the project manager for the larger commercial company Opp and Seibold, and the first two men have both build experimental, “model homes” in the area, mostly to demonstrate that Walla Walla is capable of harboring sustainable construction. I have put specifics of their alternative construction methods in my case studies report. While their homes are exciting demonstrations of conscious design, their view is long term. Mr. Petrello does not plan to move for over twenty years. Mr. Nelson built his house as a model home to try and spark an interest in sustainable design in his clients. Neither of these motivations are typical for homeowners, especially those planning to stay less than ten years (as do most families).

My chief interest was trying to see what was available for the larger market and try to promote it in the community. This is what I did the second half of the semester. I spent most of my time researching different options that the builders had used to see if they were applicable to a larger market. Since people move often, paybacks of less than five years are not usually economical for homeowners. In my research I found that the best investment that people can make to lower their environmental impact (and energy costs) is to use super-efficient windows, change their lighting sources, use solar hot water heaters and a energy conservative plan for their landscaping.

Many of the ideas that I had about living off the grid cheaply and easily were changed as a result of this internship. I realized in order to reach a wider audience for sustainable building, the cost for many of these products must come down. This leads to a catch-22: demand must rise so that companies can make use of the economies of scale before prices can come down, but not enough people will buy these products with prices at their current levels. I am disappointed that my research proved such glum results, but I am grateful to have a truer understanding of the costs involved with retrofitting, and adjusting components compared to the economic benefits. A whole system sustainable design would likely have greater savings than just one or two retrofits, but it is only possible to analyze one component at a time.
The individual component approach probably overestimates payback times, but it is something a designer would have to address with individual clients and compare that to the goals of the project. Individual technologies or components can be more expensive, however, they might bring down the total cost of the project. For example removing an HVAC system from a residential project could save electricity costs by 40% or more a year and cut out the cost of a furnace and ducts, but the costs of a radiant heat system combined with solar hot water heater are higher than a normal boiler. So the total cost of the project (and thus the payback) are hard to analyze on an individual component basis.

In talking with large scale commercial builders, the feeling I got was that meeting code was sustainable. Exceeding code was not economically feasible, or even desirable from their perspective. Mostly, they told me that the same constraints that applied to residential structures applied to commercial buildings. I understood that when deciding components for commercial buildings they would often recommend higher efficiency windows, and steel construction, but their input on the design process was not focused on making profound sustainability goals a priority for their clients.


I thought that my internship was an interesting exercise in understanding the complexity of the problem in Walla Walla. Most of Joe Petrello’s clients are only in their houses for at most five years; Dirk Nelson’s are not much different. Opp and Seibold’s and other commercial builder’s clients usually have between five and fifteen year lifecycle analyses for their projects. This limits the products and services that people are willing to invest in to those with short paybacks. This is hugely limiting to the sustainability movement. Without changing the way we see buildings culturally, or changing accounting practices, I do not see an easy way out of the short term thinking dilemma. Perhaps changing county building codes would be an effective solution. This problem could easily lead to a lifetime of work, and I am glad that I got a chance to start understanding it better earlier.

I found that the builders Joe Petrello and Dirk Nelson were both extremely helpful, and knowledgeable people. I was particularly grateful for a chance to work with two people who know so much about their particular projects and could help share it with me.

Talking to both the sustainable builders a pleasure and an inspiration for me. After taking a three hour tour of Mr. Nelson’s house, I was convinced that his ideas were easy to implement and could make Walla Walla a model community for building sustainably. With some planning, and a holistic cost analysis, I feel confident that Mr. Petrello and Mr. Nelson’s ideas could be incorporated into new designs across the valley with less financial cost. It would take a full project analysis to be able to demonstrate the viability of these projects.

I have been working on real estate projects for two years, and Mr. Nelson’s house was by far the most interesting house that I have seen from both an engineering and aesthetic point of view. Because of the advanced technologies the two builders utilized, I was not familiar with the more avant-garde techniques that either Mr. Nelson and Mr. Petrello used, specifically the SIPS foam panels in Mr. Nelson’s house, and the specifics about the windows they used. Although I was initially uncomfortable talking with them technically, I was later able to ask more specific questions.

I still believe that it is possible that Walla Walla can become a more sustainable community, but I have found that incremental changes are not the answer. I am not sure whether legislation or ordinances will help promote sustainable development. As Mr. Petrello mentioned, the problem is vision. People only look three to five years beyond the present when buy a house, because this is when they plan to move again, and so to invest for the long term is uneconomical. I do not know how to address this issue. I have found that in the short run Walla Walla builders could decrease energy usage considerably. For example, in the case of heating, up to 30% of the heating energy can be cut using super-insulation techniques and an efficient furnace according to Joe Petrello.

The potential is here in Walla Walla to make sustainable building a reality, the economics are just not yet in place to demand it from builders who might be willing to engage in a project like Mr. Petrello’s or Mr. Nelson’s.



My internship was extremely individually focused and driven. I had limited contact with my internship sponsor, Karen Yager after our initial meetings other than occasional reports on the progress of my work. I think that the next intern will be well-served to stay in close contact with the board of the NWREF and Karen Yager who I found gave excellent support during my internship.

Generally I feel I accomplished my goals, although I retrospectively ought to have spent more time in the community helping to spread interest in sustainable building. My time on researching individual products and techniques was valuable to me, but probably did little to directly further the goal in sustainable building in Walla Walla. That said, there is now a record of sustainable resources specifically aimed at Walla Walla and its environment which will be useful to anybody who is interested in this project in the future.

I have laid the groundwork for the next intern to be able to work on giving out the information to builders and to continue the outreach program where I was least successful. This would give the sustainable methods greater exposure in the community and perhaps inspire more people to work with either Mr. Nelson or Mr. Petrello.

The next intern ought to be focused on spreading the word about these techniques to builders. This could be many more meetings rather than individual research.


Case studies:

At least two houses in Walla Walla have used many of the products and services described in this pamphlet. The total cost of these houses was about 20% higher than a conventional house, but many of the technologies they utilize are cutting edge and have gained wide acceptance in the general building community. These two homes are models for what can be accomplished using sustainable building techniques. Even by only using some of techniques described in the case studies, the information can be a great resource to develop sustainable plans for any home. The first home is an earth covered, passive solar house in Walla Walla sitting on one acre. It is a study in alternative building methods, and thermal engineering to reduce heating and cooling costs wherever possible.

The house is super-insulated, the walls are between rated between R-30 and R-40. It is roughly 2,200 ft2, built with post and beam construction. The walls between the posts are foam and steel panels called SIPS (Structural Insulated Panels), which combined with the plywood surrounding the walls help to insulate the walls. The foundation is a concrete slab for maximum solar mass. It has no covering, the slab was acid etched in order to give it a “homey” feel, it look more like an uncut marble slab than concrete.

The home sits on one acre that has been landscaped so as to direct the more temperate air from the creek up towards the house. Fifteen foot earthen berms keep the house private without fences, and have the added benefit of funneling cool air towards the house from the creek at the bottom of the property. The berms create a valley between them running north-south. At the bottom is Russell Creek. The air around the creek is cooler in the summer because of the trees’ shade, and the tree’s evapotranspiration processes. This cooler air is funneled up towards the house by the berms by summer breezes. During the winter, the berms help block the wind from blowing across the house and acts as insulation. The berms help keep the house temperate year round performing opposite functions in summer and winter. Trees by the creek help shade the home during the summer, but during the winter the deciduous trees allow the sun to penetrate the house and heat the home passively.

The solar hot water heaters on the roof provide almost all of the heating for the house. They heat 10,000 gallons of water to roughly 140º F all year round using an indirect evacuated tube collector. The hot water is circulated through a radiant heating system throughout the whole house, which combined with the passive solar mass of the concrete floor, eliminates the need for a furnace. Air conditioning too is superfluous due to the super-insulation and the earthen construction on many of the exterior walls which traps thermal energy and keeps the structure at a fairly constant temperature year round.

The conscious design of the house requires no forced air systems, no duct work, and no furnace or air conditioner. The only air circulation comes from three paddle fans in the ceiling. They are reversible, so during the winter they push hot air down towards the floor, and during the summer they push hot air out the windows near the top of the house. The energy savings are such that the total utility bill for the house is less than $900 per annum. This home is designed to the point where it there is as little thermal contact between the outdoors and the house as possible. All the windows are low emissivity, and all the exterior contacts are wood which is almost non-conductive.

The house is on the electrical grid, because the photovoltaic cells were not cost effective in the builder’s mind. He chose instead to use products with faster paybacks. The walls and the passive solar technologies, along with the sod roof have paybacks of less than ten years. As mentioned before, photovoltaics have a payback time of twenty years, so they are not cost effective. The house uses mostly compact fluorescent lighting, which saves about 75% of the lighting cost in the house compared to standard incandescent bulbs.

The second home is a straw bale house totally off the grid several miles outside of Walla Walla. This home utilizes photovoltaic cells so it does not need any external source of power. In this case, the house is in a rural part of the county, far from a central power supply, so the cost to hook into the grid at the home site would have been comparable to buying the solar panels, so this house is fully powered by photovoltaics. Here, the walls are straw bales, which provide a rating of roughly R40. The builder believes that above R40, although the cost of installing additional insulation does not decrease, the walls are so well insulated that there will be very small heating savings. In other words, R40 is the point of diminishing returns for insulation.

In constructing this house the builder used as many sustainable processes as possible, which cost him roughly twenty percent more initially, but over the lifetime of the house, he believes that he will save the money. The biggest outright cost were the photovoltaic panels which are not recommended for people who do not intend to live in a house for more than twenty years. The windows are argon-filled double paned with R-values that are roughly R-6 (far below the walls’ ratings, but much more insulation value than the usual windows). These windows were calculated to have a payback time of about three years over the conventional windows.

Heating comes from a super-efficient furnace, which the builder strongly recommends as a worthwhile investment. This super efficient furnace has shaved fifty percent of natural gas consumption for a similarly sized house (2000 ft2). Although the new furnace initially cost almost 40% more, the utility bills for a year are only about $700. This buys natural gas and two cords of wood for a wood burning stove.

Generally, the builder believes that the best and most effective sustainable building practices for other builders would be to use super-insulation around R-40, use argon filled windows, and buy a heat pump, or a super-efficient furnace. The total cost for a building built with these considerations in mind would be about five to ten percent, which could be easily recouped within five years.