Imagine dining room views of Seattle's Space Needle. The residents of Prospect House have the opportunity to see this distinctive skyline every day from their Kolbe windows and doors. Custom, 90-degree corner units match with windows stacked floor-to-ceiling to capture the vistas from all angles.
"The Kolbe windows are the most prominent feature in our home and a matter of extensive deliberation. It was a critical decision, as many functional and aesthetic choices hinged on the windows," says Celeste Hyde, Prospect House's owner. "We're very pleased with the beauty and the performance of Kolbe's windows, which were equally important to us. The windows fit with the home's industrial, sophisticated and modern appearance, while offering all of the residential comforts and graciousness found in a family home."
The slope of the site, more than 26 feet from street to alley, required a multi-level solution. "The owners wanted to maximize the views, pulling the living levels up as high as codes would allow, while maintaining generous ceiling heights. For these reasons, solving the vertical dimensions of the house was a major task during the design process," says Janof Hald Architecture's Amy Janof, AIA.
As homeowners, Celeste and Will Hyde were instrumental in the design process. Will Hyde adds, "Performance, particularly the energy-efficient heat control for a south-facing aspect with high winds on a sloping hill, has exceeded expectations. Our 19-foot wall of windows is so efficient and attractive, we have decided against window treatments in that space."
"Aesthetically, the site's tremendous views over Elliott Bay and downtown Seattle demanded as much glass as possible on the south façade, and both the owners wanted to capture the flavor of Seattle's older warehouse and manufacturing buildings," Janof explains. "The window walls are one of the central stories of Prospect House; the drama they provide, both inside and out, is central to its success."
To achieve this dramatic design, Janof says, "We originally looked into both aluminum and steel-sash windows, but neither construction type gave us the U-values required by the strict local energy codes. The solution would have to be a wood window, with aluminum cladding for exterior durability. Kolbe's Ultra Series had the most authentic muntin design of all the clad wood windows we considered, and the 30-year warranty on the finish made the choice a practical one as well."
Enhancing energy efficiency, Kolbe's Ultra Series windows are glazed with high-performance ThermaPlus LoE insulating glass. A bronze spacer contributes to the thermal performance. Performance Divided Lites (PDLs) preserve the intended performance, while simulating the look of true divided lites. All of the attributes also helped in meeting the home's ENERGY STAR® requirements.
"Kolbe's high performance glazing option not only provided us with an excellent thermal U-value; the shading coefficient of the clear glass is exceptional, without having to go to tinted. This has allowed the house to be comfortable without air conditioning, as well as protects the furnishings from sun fading," adds Helen Hald, AIA, co-founder and principal at Janof Hald Architecture.
She continues, "We employed Kolbe's windows in two different applications 1) as a window wall on the big view side and 2) as 'punched' openings on the street side, where a more conventional façade was welcomed by the context of this venerable neighborhood."
Kolbe provided more than 100 large windows throughout Prospect House, many of which are operable to allow both natural light and natural ventilation. Push-out casements and awnings aid in Passivhaus design, as do the exterior doors. Kolbe also crafted more than 20 door units to complement the windows in their contemporary appearance and high performance.
"Because the site also has a fierce wind exposure, the 19-foot-high window wall required an interior wide-flange steel frame to brace it both vertically and horizontally," says Janof. "This structural solution enhanced the vintage factory feel the owners desired, while yielding a façade virtually free of columns or walls, allowing the windows to butt together with both factory- and site-mulled connections. Kolbe's integral steel reinforcement for high-wind situations was instrumental in allowing us to maintain the fewest structural interruptions possible."
Hald agrees and adds, "Kolbe provided detailed shop drawings for our review, which helped streamline fabrication and installation."
Classic Window Products assisted with the products' selection and worked closely with Joseph McKinstry Construction Company to ensure that each unit was properly installed. "Classic has a long history of relying on Kolbe's products for Washington State's high-profile residences, light-commercial business and notable projects such as the Seattle Aquarium," says Kolbe's regional manager, Bryan Kujawa.
"We've had the pleasure of working with Helen and Amy for many years, too," says Mike Cler, Classic Window Products' vice president. "We were able to meet all their needs, on behalf of the homeowner, with Kolbe's products – from the push-out casements in oversized widths to the performance of the glass, from the consistency of divided lites throughout the house to the black finish on the exterior."
To minimize maintenance and enhance the products' lifespan, the exteriors of Kolbe's windows and doors are finished in a durable, PVDF fluoropolymer coating. This Coal Black coating was selected to be distinctive, while blending with the natural surroundings. Supporting the homeowners' sustainability design goals, Kolbe's Ultra Series products include recycled aluminum content in the exterior cladding.
On the interior, the oil-rubbed bronze hardware accents the painted wood. According to Hald, Kolbe's in-house finishing helped save money and time at the job site: "Kolbe factory-primed the interior side of the wood windows, which reduced the scope of expensive field painting." Janof Hald also worked with Kolbe to identify other economies of scale, such as selecting stock-sized doors and maximizing the sizes of factory-mulled window units based on the sizes of the delivery trucks.
Kujawa summarizes, "Combining practical knowledge and creative vision, Prospect House stands as a livable, beautiful showcase of Kolbe's ability to meet high performance requirements and contemporary design styles."
Honoring these accomplishments, Prospect House earned IDEAS2 - Innovative Design in Engineering and Architecture's 2011 National Certificate of Recognition in the "Less Than $15 Million" category from the American Institute of Steel Construction.