Final Report: Designing and Demonstrating Sustainable Multi-Family Attached Housing

EPA Grant Number: SU833192
Title: Designing and Demonstrating Sustainable Multi-Family Attached Housing
Investigators: Melcer, Mathew , Ho, Ly Chan , Dibble, Brian , Nicoletti, Diana , Girrard, Hillary , Hall, Lauren , Peck, Leah , Moller, Ryan
Institution: Washington State University
EPA Project Officer: Page, Angela
Phase: I
Project Period: September 1, 2006 through August 31, 2007
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2006) RFA Text |  Recipients Lists
Research Category: P3 Challenge Area - Sustainable and Healthy Communities , Pollution Prevention/Sustainable Development , P3 Awards , Sustainable and Healthy Communities

Objective:

For this project, students at Washington State University Spokane’s Interdisciplinary Design Institute will research, design, assist in construction of, and evaluate sustainable, multi­family attached dwellings. The students’ charge is the development of a cost-effective, environmentally-friendly housing model that is innovative, responsive to the local environment, and sensitive to the needs of the end users. The project will be led and implemented by an interdisciplinary team of students majoring in interior design, architecture, and landscape architecture. The students will collaborate with Habitat for Humanity Spokane and the Northwest EcoBuilding Guild to design and construct multi­family housing structures that can be built rapidly using relatively low-skilled, volunteer labor, generate minimal waste in construction, and reduce environmental and economic costs. The project will provide Habitat for Humanity-Spokane with a new precedent in building design and construction, and provide a focus point for innovation and sustainable housing in the Inland Northwest. Finally, the students will extend their education beyond the classroom to actually improve conditions for People, Prosperity and the Planet.

Project Goals

  1. Determine environmental, human health and economic costs and benefits of building with alternative, ecologically sustainable building materials and systems as compared to conventional methods.
  2. Maximize energy efficiencies through building design, specification of materials and methods, selection of appliances and equipment, and design of the landscape.
  3. Minimize use of materials and finishes that generate hazardous by-products during manufacturing, use or disposal.
  4. Design responsive to external environmental factors by incorporating passive heating and cooling strategies, day-lighting, ecologically sound landscape design, and efficient storm water management.
  5. Design to end-user needs, considering health, community, culture and aesthetics.
  6. Reduce the overall cost of sustainable housing.

Summary/Accomplishments (Outputs/Outcomes):

The primary outcome of this research is a housing product that addresses evolving human needs, economic viability, and issues of environmental impact. The product is referred to as the sma|rt_1 home. Sma|rt is an acronym for sustainable, modular, and adaptable residential technology. A pilot project including four duplex versions of the sma|rt_1 home will be built by Habitat for Humanity-Spokane with assistance from students from Washington State University Spokane beginning in July 2007. Habitat for Humanity-Spokane reserves the right to alter any design features of the sma|rt_1 home during implementation. The site for these demonstration units is located within the city limits of Spokane, WA.

People: evolving human needs
Through unique design features, the sma|rt_1 home can adapt to meet the current and evolving needs of the homeowner. Building upon the concept of the grow home (Friedman, 2001), owner improvements can be made to the sma|rt_1 home in response to changes in lifestyle. Unfinished attic space and an integrated covered porch provide areas for future expansion. This allows for a three bedroom unit to be improved over time to accommodate four, five, or six bedrooms without altering the structural form of the building. This translates into a 55% net square footage increase from 1,120 to 1,740. Homeowners with limited building skills can perform these modifications with little or no professional assistance. The owners of the pilot project units will have the requisite skills for these types of modifications. All Habitat for Humanity homeowners are required to contribute 500 hours of sweat equity in the construction of their home. This helps them develop basic skills in carpentry and home construction.

The design of the sma|rt_1 home includes front and rear covered porch areas that are integral to the form of the building. These are intended to serve dual functions as homeowner amenities and solar shading devices. Alternative kitchen and dining room arrangements are identified to meet specific cultural or functional homeowner needs. Provisions for interior material and finish options are also provided. Design plans are developed for future homeowner initiated improvements including bedroom and bathroom expansion, additional built-in cabinetry, upgrades of interior trim, exterior benches and planting areas, and energy efficient appliance upgrades. A homeowner’s manual has been developed for the sma|rt_1 home including in-depth instructions and drawings to guide these home improvement projects. This empowers the homeowner to improve their property in an affordable manner while increasing resale value and aiding in economic security and independence.

Prosperity: economic viability
The sma|rt_1 home targets the first time low-income homeowner. Affordability is achieved through lower initial construction costs and reduced life cycle costs due to simple, responsive, energy efficient design. The sma|rt_1 home realizes lower initial construction costs as a result of efficient use of building materials and minimization of waste. The design is based on a two foot module with an overall dimension of 14’ x 52’ for a single unit (duplex structures are 28’ in width). A major benefit of this approach is that many conventional building materials are sized as a function of the 2’ module. This saves in material waste and aides in rapid construction.

Over the life of a structure, energy use consistently represents one of the highest expenses, and given future predictions of mounting demand and escalating costs, this will likely increase in significance. Reduction of energy use is achieved in the sma|rt_1 home through a combination of environmentally responsive design strategies including passive solar design, day-lighting considerations, passive ventilation, and highly insulated wall and roof assemblies. By decreasing energy needs for heating and lighting, the sma|rt_1 home reduces the overall, long-term expenses associated with the home. These efficiencies and the resulting cost savings help to make the economic benefits of homeownership possible to lower income levels.

Planet: issues of environmental impact
The sma|rt_1 home combines energy efficient and environmentally-responsive building design with low impact site considerations and sustainable construction materials and methods. Insulated concrete form construction for walls combined with a structural insulated panel roofing system are identified as the most energy efficient, cost-effective, low skill labor friendly, and environmentally benign method for the exterior construction. Roof gutters will be installed that feed into retentions cisterns to provide water for landscape maintenance. Generous south facing windows are incorporated in the design to provide natural light and passive heating. The design specifies low toxicity construction materials and finishes to support human health and comfort through improved indoor air quality. The sma|rt_1 home integrates energy efficient equipment, and low flow shower heads, toilets and faucets. Energy star appliances have been identified for the refrigerator, dishwasher, and clothes washer. Surface mount and recessed can lighting is specified using compact fluorescent lamps. A high efficiency electric-on-demand water heater serves the radiant heating and domestic hot water needs. To maximize the life of the on-demand heater, a central water softener is also specified. Because it is a duplex, the sma|rt_1 home will also enable higher housing density with reduced costs and environmental impacts as compared to single-family detached homes.

Conclusions:

The research and design portion of the project determined that much progress in developing sustainable housing is possible. Designing low-cost, sustainable housing requires consideration of the site, building structure, and interior environment as a holistic and integrated system. The research and design portions of this project have been completed, but construction of the actual units will not begin until July 2007. As a result the conclusions that can be drawn from this project will not be completed until the post-occupancy evaluations can be made between fall 2007 and spring 2008. More specific conclusions will be possible once the structures are built and these evaluations have been conducted and analyzed.

Proposed Phase II Objectives and Strategies:
During Phase II, students will research, design, assist in construction of, and evaluate multi­family housing units exploring higher density living options. This will include the design of multi-family attached dwellings in triplex and multiplex configurations for implementation by Habitat for Humanity Spokane. A site is currently being considered that can accommodate as many as 60 residential units under current zoning regulations. The scope of design will be expanded to include infrastructure and community amenities including access roads, driveways, signage, communal spaces, and sidewalks. The students will develop a cost-effective, environmentally-friendly, community housing model that affords higher density applications, is responsive to the local environment and sensitive to the needs of the end users.

The project will be led and implemented by an interdisciplinary team of students majoring in interior design, architecture, and landscape architecture. Partners will include Habitat for Humanity Spokane, The Integrated Design Lab at Washington State University, the Northwest EcoBuilding Guild, and a new partner, Zeck Butler Architects, PS. The students will collaborate with these partners to design and construct multi-family housing structures that can be built rapidly using relatively low-skilled, volunteer labor, generate minimal waste in construction, and reduce environmental and economic costs. The project will once again provide Habitat for Humanity-Spokane with a new precedent in building design and construction, provide the students with an opportunity for hands-on learning opportunities, and provide a focus point for innovation and sustainable housing in the Inland Northwest. Finally, the students will extend their education beyond the classroom to actually improve conditions for People, Prosperity and the Planet.

Phase II will also involve data collection and analysis of the 8 unit multi-family demonstration units built as a result of the Phase I investigation. A post occupancy evaluation of the building units will be done at regular intervals. This will begin at the time of occupancy with re-evaluation to occur after 6 months, 1 year, 18 months, and 2 years of inhabitance. The method for the evaluation will involve both qualitative assessment of use and satisfaction of the occupants and an evaluation of building performance in terms of energy use and cost, material durability, interior day-lighting levels, and maintenance costs.

Prior to the Phase 1 investigation, students collaborated with Habitat for Humanity Spokane in the research, design and construction of a single family detached home built using straw bales. Preliminary data analysis suggests higher levels of energy efficiency in the bale home as compared to conventionally framed homes.

Objectives for Phase II

  1. Determine environmental, human health and economic costs and benefits of building with alternative, ecologically sustainable building materials and systems as compared to conventional methods.
  2. Maximize energy efficiencies through building design, specification of materials and methods, selection of appliances and equipment, and design of the landscape.
  3. Minimize use of materials and finishes that generate hazardous by-products during manufacturing, use or disposal.
  4. Design responsive to external environmental factors by incorporating passive heating and cooling strategies, day-lighting, ecologically sound landscape design, and efficient storm water management.
  5. Design to end-user needs, considering health, community, culture and aesthetics.
  6. Reduce the overall cost of sustainable housing.
  7. Design for higher densities than were achievable in the previous project.
  8. Design to promote a shared culture of sustainability between homeowners and to serve as an example for the community at-large.

Supplemental Keywords:

global climate, indoor air, toxics, pollution prevention, waste reduction, waste minimization, northwest, construction. health effects, human health, sustainable development, clean technologies, innovative technologies, community-based, cost effective, EPA Region 10, architecture, interior design, construction management, landscape architecture, sustainable housing, energy efficiency, solar energy, passive solar energy,, RFA, Scientific Discipline, Sustainable Industry/Business, Sustainable Environment, Technology for Sustainable Environment, Environmental Engineering, sustainable housing, sustainable development, green design, environmental conscious construction, green building design, alternative materials, straw bale, construction material, pollution prevention