The Enclave Residence will be a Certified Passive House (Passive House Classic). It is a new house for a family who lost their home in the Marshall Fire, a devastating fire that burned more than a thousand homes in Boulder County, Colorado, on December 30, 2021.
Sustainability and resilience are fundamental drivers of the design. The house is constructed with pre-fabricated wall and roof panels from B.Public Prefab. The 14” thick panels are superinsulated, airtight assemblies that provide R-values of R-52 at the walls and R-59 at the roofs (blown-in cellulose), with integral airtight and weather-resistant membranes. The panelized building system results in an average of 80% less energy usage than code-built homes, 95% less construction waste, and 30% faster construction time.
The house will use heat pump technology for heating, cooling, and water heating, and an ERV system for natural ventilation. It will be all-electric and will include PV panels and electric car charging. It prioritizes environmentally responsible companies and materials for interior finishes such as tile, carpet, and window coverings. Firewise construction is considered throughout. Non-combustible exterior materials include a corrugated metal roof, aluminum-clad triple-pane wood windows, fiber-cement panel siding, cementitious stucco, and fiber laminate planks. The design minimizes envelope penetrations with the ERV system, by using ventless equipment (ventless dryer, recirculating kitchen hood, passive ventilation plumbing vent), and by not having eaves or a vented roof assembly.
The design of the house celebrates the thick wall assemblies with massing and material choices that give a nod to southwestern-style adobe houses, a typology that the owners particularly like and feel a personal connection to. The massing and siting, material and color selections, window detailing, and scupper and rain chain design all evoke a modern take on traditional adobe homes.
The design also focuses on large glazed openings and clerestory windows to juxtapose the heaviness of the thick walls, flooding the house with light and opening it to mountain views. The clerestory windows are designed in a terraced southern-facing orientation to take advantage of the southern sun while providing interior views of the sky and creating a variety of ceiling heights and spatial experiences. Expansive windows on the west are designed with exterior overhangs, with depths optimized per energy modeling to maximize performance. Passive-certified windows with carefully calibrated glazing specifications are detailed at the optimal location within the deep assemblies for energy performance. Window installation details include interior insulation wrapping the frames to insulate the weak spots in the envelope. Air-sealing at window openings is carefully detailed, and all details are optimized per thermal bridging and condensation analysis.
The design places the house low on the site, furthering the grounded feel of the design while providing accessibility for aging-in-place considerations. A ramped front entry walk leads to the front door of the ranch home. All essential functions are on the main living level, with accessory living spaces on the basement level. Foundation details and transitions from concrete foundations to pre-fabricated envelope components are carefully detailed with a continuous airtight layer and thermal breaks to ensure that the robustness of the panelized system extends to the site-poured foundations.
The project is currently in construction, with an estimated certificate of occupancy in December 2023.