Reno Home Using ICF and SIP Construction
Site characteristics or focus during construction or remodel:
Owner designed a passive solar home to take advantage of the solar capabilities of the lot.
Building Construction Type:
This project utilized Build-Block ICF (Insulated Concrete Forms) for the walls and Structural Insulated Panels (SIPs) for the roof.
Site Use and &Protection Measures Before & During Construction (LEED Cat I):
Standard Best Management Practices (BMPs) per city requirements, including silt fences and slope protection. No changes to the existing grade of the lot were required.
Outdoor & Indoor Water Efficiency Measures in Project (LEED Cat II):
Zero-scape landscaping was employed on the exterior. The entire focus on the inside of the house is on a centralized plant area so plants can be watered in a central location. Standard low-flow fixtures and toilets were also installed.
Energy Efficiency & Renewable Energy Measures Used in Project (LEED Cat III):
This residence was designed as a passive solar house with concrete mass within (walls and floors). The house is built into a hill allowing optimal efficiency achieved with less exterior wall area. ICF walls have an R-32 rating, and SIPs on the roof achieve a R-49 roof rating; in addition, there is a false ceiling which further increases the ceiling rating. Windows are all Low-E and window frames use low conductance/high efficiency materials. Fiberglass doors are utilized throughout house—these doors have the highest R-value of doors on the market. Sanyo Solar PV panels (28-180 watts each) create in excess of five kilowatts of output; a grid tie system utilizes Xantrax inverters.
Space and Water Heating Systems:
There are multiple systems on board that can be selectively used depending upon the different fuel source/energy technology pricing/economics:
- The primary source of heat is Passive Solar
- Secondary system—an electric hot water and radiant floor system that runs off the PV panels
- Third system—a gas stove with extensions in multiple locations as well as intakes that pull the cold air from one side of the house and blow it out the other side of the structure
- Fourth system—a 0.7 gram per hour wood-stove
Green Materials and Green Measures Implemented in Project (LEED Cat IV):
Salvaged steel was sourced from Reno Salvage for this home, and building materials were reused wherever possible to minimize the scrap that is normally generated in the building of a tract home. Retaining walls on the site were constructed of natural rock found on the property. The conduit for their PV system was constructed of discards that were patched together. The local plumbing distributor was the source for these pieces, which were obtained at no cost.
Indoor Environmental Considerations Used in Project (LEED Cat V):
No carpets were installed in the residence, eliminating any VOCs. The home features all concrete floors. The structure features an open floor design, with minimal walls. Clerestory windows are integral to the design, creating a natural ventilation effect, as well as windows located low on the walls to complete the convection cycle. The house is situated on a hill next to a ravine providing excellent natural ventilation through the structure. Centralized interior vegetation area allows plants to keep the interior air fresh.
Subjective Evaluation/ Design Considerations: How well has the structure achieved its design goals? What would be done differently the next time?
The design works very well—a recent heat wave with temperatures in excess of 100° saw the structure remain comfortably cool, in spite of the fact that there is no swamp cooler or air conditioning in use. The owners have plans to someday install a solar hot water system, based on the home’s performance in the winter months.