Seattle | Washington
Julia Place Apartments is a new, five-unit apartment building located in the heart of Capitol Hill in Seattle. To work sympathetically with its neighbors, we conceived of Julia Place as a large house, using a gabled roof form to tie into the small apartment buildings and townhomes immediately adjacent.
The building stretches from east to west, with extensive south exposure for all dwelling units. We took advantage of the long, narrow configuration by providing cross-ventilation in all dwellings for summer-time cooling.
ENERGY USE: Our client brought to the project a desire to make the building very resource efficient. While this is not a net-zero project, many measures were taken to improve the energy and water efficiencies of the building well beyond current codes.
The owner requested that durability and low maintenance be a priority for the design of the building. Beyond the wish to reduce energy and water use, our client also brought a desire to provide for the under-served in the local community.
Three of the five apartment units are available to a lower-income tenant. One of the units is planned as a fully accessible, type A dwelling unit. This project is now complete and fully rented.
During design, we analyzed several different options for envelope improvements and heating systems, investigating both individual and combined HVAC options. During our discussions, it was learned that the owner was very interested in providing radiant floor heat as a feature of the building. As such, the decision was made to use hot water for space heat.
The heating system installed at Julia Place features a highly efficient air-to-water heat pump linked to a set of thermal pre-heating panels. The hot water is used for both space heat and domestic uses.
A high-efficiency gas boiler is provided to boost heat output on unusually cold days. In addition to the solar thermal panels, the pitched roof supports a 6kW PV array that partially offsets the power demand by the entire building.
BUILDING ENVELOPE COMPONENTS AND FEATURES:
-Roofs: R-49 ceiling (blown cellulose or hybrid)
-Walls: R-25 walls (R-21 batt ADV framed w/ R-4 foam exterior sheathing)
-Floors: R-45 framed (batt), R-10 slab (fully insulated)
-Windows: U=0.32 (fiberglass double glazed, low-e)
-Ext. doors: U=0.25 (fiberglass w/ low-e glass)
-Infiltration: ACH = 0.32
-Lighting: All lighting in the building is Energy Star rated fluorescent or LED
-Appliances: All appliances are Energy Star rated
LOW IMPACT DEVELOPMENT AND RAINWATER CATCHMENT: The street on which Julia Place is built has no storm sewer available. As such, the city initially asked for a storm sewer extension to be installed as a condition of the project. Given the small size of our building, this would have been an onerous requirement. At the same time, the owner was interested in providing a significant quantity of rainwater for re-use.
By maximizing rainwater catchment, and by utilizing intensive LID (low impact development) measures, we were able to reduce storm water flows to such a degree that the City eliminated the requirement for the storm water sewer extension. Harvested rainwater for Julia Place is stored in the crawl space under the building’s main footprint. Two 60” diameter pipes are used to store rainwater, collected from the roofs only.
The tanks provide 5,800 gallons of rainwater storage. The water is filtered at several locations and pumped to the dwelling units for laundry and toilet uses. The water is also used to meet a significant portion of the irrigation demand for the site. If the tanks empty out during the year, an automatic control switches to city water until the tanks are filled up again.
