ENERGY AND HEALTHY SPACES
Cars are tuned to perform, why not homes?
We hear terms like “high performance” and “net zero” often. The more I have learned about these terms, the more real and exciting they become. High performance means super-energy-efficient but also applies to homes that are designed and engineered to be air and water tight. Due to streamlined construction processes, advanced building materials, and the reduction of the cost of solar photovoltaics, it is now within the reach of the average homeowner to build or retrofit to net zero energy (meaning the house makes as much or more energy than it consumes). By the nature of their design, these homes are also much more comfortable, durable, and healthy than non-performance homes.
“Sustainability” implies that when we carefully design for high performance we are trading the use of Earth’s non-replaceable resources with the resources that are replaceable or renewable. For example, solar power is a renewable resource, fossil fuels aren’t. As a lifestyle practice “sustainability” implies less consumption, and therefore less carbon admitted into the atmosphere as a result of manufacturing and transportation of consumables.
What about cost?
A high-efficiency home only costs about 5 to 10% more to build then a code-level home but pays back quickly it lowered utility and maintenance bills. Occupants’ medical bills are often dramatically less as these homes use non-toxic materials, and all but eliminate air, water, dust, and organism infiltration. These homes appraise for more than code-level homes, and studies most always show they sell faster. A cash flow study usually surprises clients and demonstrates the affordability of advanced homes.
Why aren’t there more high-performance homes being built?
The main obstacle to advanced building is complacency. Some builders and buyers put more thought into the purchase of their new car or TV than in their house. Some builders are reluctant to learn new technologies and practices because it’s inconvenient to change. Another obstacle to overcome is the myth that high-performance energy homes are too expensive or take too long to pay for themselves. Solar PV has dropped 60% in cost since 2009 and tax incentives rebates etc. take the pay-back down to less than 10 years. A final obstacle is the preconceived notion that the terms “green” and “sustainable” only relate to the fringe environmental activists. On the contrary, most everyone wants to save money, live healthier, and contribute to helping the earth at the same time.
Can high-performance design work with the style house I want?
I continuously design projects that incorporate these advanced systems with inviting aesthetics and non-modern styles. Insulated Concrete Forms (ICF) look like styrofoam Lego blocks, and are stacked and filled with concrete and steel reinforcing. Traditional wood and masonry products can be applied to the exterior, and drywall, tile, etc to the interior, just like any home.
The ICF wall system has been proven effective for many years, and is beginning to be used in more and more projects across the country and world. The system creates a strong, efficient, and air-tight home. Due to it’s tightness and insulative qualities, the heating and air-conditioning systems can be much more efficient. Fresh air is filtered and regulated by the system, as opposed to leaking into the house, along with contaminates and organisms.
Wood alternatives to ICF walls include staggered-stud walls and traditional studwalls with wider studs to allow for thicker insulation and gap-sealing. Panel materials such as expanded polystyrene (EPS) and poly-iso can be applied to the exterior for additional insulation. Allergens, molds, moisture, and temperature can be controlled further using a sealed crawl-space instead of a vented one, especially when the reduction of exposure to mold and other allergens is high on the owners’ priority list. Sealed crawl spaces are insulated too, and offer a “passively-conditioned buffer” from the exterior to the interior.
Sounds good. How do we incorporate these systems into my design?
Throughout the custom design process, I work to achieve the energy and environmental goals that are most important to my clients. I also work with the subcontractors and enviro consultants to optimize the balance between performance and cost. Each project is different, and the reward for successfully implementing these systems is worth the effort. It’s great to see my clients get into the study of building science and steer their project towards high-performance and healthy spaces.