Flexhouse | 33160 N. Cove Rd., Wildwood, Il 60030 view  map
Flexhouse innovatively combines several design movements into one house including passive solar, passive geothermal, as well as universal design, creating a sustainable home that can transition to all phases of one’s life.

SIZE: 1,720 square feet

PROJECT TYPE: Single Family – New Construction

LEED for Homes (Pending – Gold)

HERS: 49

Welch Design LLC
1427 Wild Iris Lane, Grayslake, IL 60030

Project Website: http://www.welchdesignllc.com/
Facebook: https://www.facebook.com/welchdesignflexhouse/


Flexhouse is a passive solar house with triple pane windows throughout. It is insulated with one inch of closed cell spray foam and blown and bibbed fiberglass. One of the unusual features, which can also be found in Rocky Mountain Institute’s innovative headquarters in Colorado, is a trombe wall covered in metal panels and filled on the interior with phase change material. Facing the windows on the southern side of the house, the 2 story wall receives direct sun rays during the winter and is shaded with overhangs in the summer. The phase change material inside the wall has the thermal capacity of a 12″ thick stone or concrete wall, making it capable of holding in the sun’s heat until the temperatures begin to drop, then releasing the heat slowly into the house over a 12 hour period.

A house this well insulated has to have fresh air constantly piped into the house, and the stale heated air needs to be expelled to the outside – wasting the heat. Flexhouse has a heat recovery ventilation system that recovers the heat from the stale air and puts this heat back into the house before expelling the stale air. It also takes heat from heated air from baths and showers and recycles the heat back into the house. Another unique feature of the house is the passive geothermal room which is a thermally isolated, 25′ long, narrow room in the basement that keeps a steady temperature of between 50 and 60 degrees year round (like a root cellar). Fresh air is piped in from 4 feet above ground down 11 feet to the room underground, then through the 25′ long 50 – 60 degree room before entering the HVAC system. If the temperature outside is zero degrees, by the time the fresh outside air reaches the HVAC system it has reached approximately 43 degrees.

Another sustainable feature are the hardwood floors throughout the home. They were milled by a local sawmill from several trees that were removed from the lot before construction.

While in graduate school specializing in sustainable architecture, Patsy Welch’s elderly parents began having physical difficulties. She began making frequent trips to Memphis, Tennessee to aid in their care. There, she saw how the townhouse that had served them so well for 25 years, now seemed to be dangerous place with uneven floor surfaces, dark hallways and small, cramped bathrooms. As a result, she began to explore ways to design a sustainable home that could easily adapt to one’s needs throughout a lifetime.

Flexhouse has three closets stacked on top of each other that conceal a future elevator shaft built to code. The are no changes in the floor levels to trip on, even in the bathroom showers, and no interior thresholds. All doors are 3′ wide, and both bathrooms have enough room for a wheelchair to make a complete rotation. The plan is very open and flexible including a second floor bedroom and bath that can be easily converted into an independent living space for a caregiver, returning adult child, etc. With hardwood floors and ceramic tile throughout, as well as cement fiber exterior siding, great care was taken to ensure the ease of maintaining Flexhouse.