Climate-Responsive Structure
In Minnesota, summers can be hot, and winters are always cold. With a record high of 114 degrees and temperatures as low as negative 60 degrees, the 174 degree variation in seasonal temperatures is extreme.
Together with several innovative Twin Cities builders, PAF Architecture has developed an exceptionally energy-efficient building package that is well-suited for Minnesota's extreme climate.
There are four key components:
- Continuous Foam Insulation - in foundation walls, exterior walls, and roof - no gaps or thermal bridging
- Thermal Mass - high density, high-specific heat exterior wall material at high volume
- Geothermal Heat Pump
- In-floor Radiant Heating and Cooling in Concrete
The building system employed to meet these criteria is: Insulating Concrete Forms (ICFs - footings to roof), with roof structure sprayed with Icynene foam. The thermal mass is provided by the ICFs, and provides a tremendous buffer between interior and exterior temperatures. The ground-source heat pump is served by PEX tubing embedded in the basement floor concrete slab, and in some cases a main level floor slab of lightweight concrete. The radiant floor system, with its own thermal mass, distributes heat evenly and comfortably.
Since 2003, PAF Architecture has designed and overseen construction of 10 homes using this system. We have found it to be a most-preferred, energy-efficient, and durable (no mold issues) way to build a climate-responsive home for Minnesota's extreme climate.
Green and Blue in Cannon Falls
Constructed in 2006, this traditionally-styled home on an infill lot in Cannon Falls, Minnesota makes use of an assortment of green building strategies. Notable green design features include:
- Continuously Insulated Concrete Walls (ICFs) - 6" reinforced concrete cavity footings to roof
- Geothermal Heat Pump
- In-Roof Solar Hot Water Heat Collection
- Radiant Floor Heating in Lower and Main Level Concrete Floor Slabs
- Icynene Foam Roof Insulation
- Roof Rainwater and Snowmelt Collection and Storage - below-garage cistern - metal roof keeps particles out of runoff
- Low-to-No-Maintenance Fiber-Reinforced Siding, Trim, and Decking Boards
- Upper-level Passive Solar Sunroom with Thermal Storage to serve North-side Master Suite
- Upper-level "Tropic Room" for Winter-time In-door Gardening
- Corn Pellet (Biomass) Stove - in lieu of gas fireplace
- Raingarden Landscaping to mediate excess Roof Runoff
To see more insulated concrete homes by PAF Architecture click the ICF HOMES navigation tab above.
