The owners had outgrown their existing 50's-era ranch home. The decision was made to raze the house and replace it with new. Admirers of Prairie architecture they asked the team to design an environmentally-sustainable home uniquely for their lot. Due to a moderately sloped site and the desire for a partially exposed lower level, the design called for the main floor to be raised well above grade. This technique was often used on many early Prairie homes in order to provide a sense of airiness, privacy and of course better views to nature, in this case a scenic golf course across the street. Due to its long-time association with Prairie architecture, natural stone is the primary masonry element for this home. In this application, a thin-stone veneer system is used. The thin-stone is laid up in a semi-coursed ashlar pattern. A blend of colors are present such as buffs, tans, grays, browns, oranges and reds. The stone is used primarily at the base of the home in order to provide a plinth which anchors the home to the earth. There are also taller elements with stone, such as pilasters and wing-walls at terraces at the front and rear. Smooth-finish limestone sills and copings are incorporated to cap off the stone veneer. Stone is similarly used on the interior: the central two-way fireplace and tall pilasters that flank a wood-slatted screen-wall.
For this residence we super-insulated the foundation with 6 high-density polystyrene foam. There are three bedrooms in the lower level, so natural light and natural materials were key design elements. Halquist “Maple Ridge stone was selected, with the challenge of securing it to the heavily-insulated foundation. With insulation installed down to the footing between metal studs (fastened to the basement wall with 8 bolts), a wire mesh screen was screwed to this assembly, and standard scratch-coat and thin-stone installation followed. A 12” deep Bedford stone sill was used to cap-off the stone veneer-over-foam system, as well as to provide a proper water table detail. The end result is a beautiful, well-insulated stone structure that secures the house to the landscape.
Above grade, the residence is insulated with 8” SIPs. Combined with a 1” protective layer of foam on the exterior, this wall system provides R-35. The trussed roof with vaulted ceiling required special detailing to accomplish our goal of an R-60 roof. Since air-tightness is equally as important as R-value, we used a hybrid system of spray-foam and cellulose. Five inches of icynene sprayfoam was applied to the topside of the drywall, and box-sills were filled to 12”. Then an additional 15” of cellulose was blown over the top to produce an air-sealed R-60 roof.
Triple-pane, argon-filled fiberglass windows (U-values below .20) were installed and foamed in place. South-facing windows in the Rain, Dining and Living rooms were outfitted with high solar-heat-gain glazing to increase the winter heat input of the sun. On a sunny day in January the temperature in these rooms can rise 4 to 6 degrees. Deep Prairie overhangs protect the house from overheating in the summer months. The precast plank main floor provides thermal mass to absorb the extra heat produced by the sun. Radiant tubing laid in a 3” bed of concrete on the main and lower floors provides heat on overcast days. A 98%-efficient condensing boiler heats the floors as well as domestic water. An air-to-air heat exchanger provides fresh (controlled) air to this otherwise air-tight home.
All of the above detailing yielded a blower-door test of 359 CFM @ 50 Pascals. This is 60% better than EnergyStar standards.
- Nicely Done, especially how the treatment flows inside I wish the exterior integration was as sophisticated as the interior. It seems like it is carried as a base plinth only without the finesse of integrating to the upper portion.
- This is the best home on the block.
- Well-planned and executed prairie design. Consistent details and materials inside and out. Great quality all around!
- Overall good composition with a pleasing use of the stone in both the exterior and interior of the structure.
Architect: Chrysalis: Home Studio
General Contractor: P.E.A. Builders, Inc
Material Producer: Halquist Stone Company