List Price: $999,000
The Property: An airy contemporary design by the architect James Nagle gives this 11-room Highland Park house a light and serene attitude. Daylight pours in from all the glass doors and windows, illuminating the open spaces and minimal detailing. From the glassy entryway that feels more like a brief passage between the front and back yards, to the oversized rooftop deck off the second-floor master suite, the house successfully blends indoors and out.

Allergy sufferers and environmentalists will appreciate how Kim Sigele, the seller of the five-year old house, collaborated with Nagle to keep the home free of allergens and toxins. There is no formaldehyde in the woods or glues, paints and stains are all low in volatile organic compounds (VOCs), and the indoor air is scrubbed by a whole-house air filtration system. All drainage from the roof and the downspouts is managed in innovative ways to minimize the chance of mold collecting in, under, or near the house. Even the window screens were handled differently: they were not dipped in insecticide.

Inside, the house accommodates residents who use a wheelchair or otherwise have mobility problems. There are no raised thresholds on the first floor that contains a second master suite, which is currently used as an art studio. The house has a soaring two-story living space bathed in daylight and overlooked by a loft area. There are four bedrooms (one of them in the basement), a small, sleek kitchen attached to the family room, and a very large yard with some towering trees. There are some nice, understated design touches, like the mailbox that empties into an unseen compartment so nobody will see unclaimed mail gathering in the glassed-in front hall when the residents are away.

Sigele commissioned Nagle to design the new house when the prior home on the site turned out to have lots of mold and asbestos. It was, she says, a sustained experiment in finding the most effective solutions for clean indoor air quality, something she expects to pursue even further in her next home—which, now that her daughter is grown, can be smaller than this one.

Price Points: Sigele would not disclose what she spent to build the house, so it’s not possible to determine what kind of premium the healthy-home features tacked onto the price.

Listing Agent: Jamie Roth of Prudential Preferred Properties, 847 219-6400; Roth is a friend of mine, but there was no favoritism here: I was interested in the house before I knew who the listing agent was.