Building Energy Performance

Achieve increasing levels of energy performance above the baseline to reduce environmental and economic impacts associated with excessive energy use. Buildings are required to meet minimum performance standards for energy efficiency.  This project has been designed to achieve more than 35% efficiency over the minimum.  In addition to the solar and geo-thermal systems, the building walls and ceilings have insulation which exceeds code minimums.  The buildings windows are thermally broken, have double glass with low-E argon gas between panes, and reduce solar heat gain in the summer. Finally, the roof of the building incorporates a white rubber roof, which reflects the sun reducing the “heat island effect” on the micro-climate, also aids in absorbing less heat than other surfaces. 


The building consists of an R-30 insulation on the roof deck (see sample material below), which is typical, and R-19 batt insulation in the walls which fills the stud cavity.  In addition, the project has 1” thick, R-7 rigid insulation in the cavity between the masonry veneer and the exterior wall sheathing.  This extra insulation is important to protect the metal studs as they can conduct the heat and cold if left against an uninsulated exterior wall sheathing.  This insulation also greatly reduces the potential for condensation occurring in the stud cavity as the dew point (where water vapor can condense) is now outside of the wall sheathing. 


Windows are thermal holes. An average building may lose 30% of its heat or air-conditioning energy through its windows. This building’s windows are thermally broken, have double glass with low-E argon gas between panes, and reduce solar heat gain in the summer. By combining Low E Glass and Argon gas, this building provides the ultimate in insulation performance.


Low Emissivity glass (Low E), reflects long wave radiation. This keeps the heat inside your home during winter and reduces heat absorption during the summer. The principal mechanism of heat transfer in multilayer glazing is thermal radiation from a warm pane of glass to a cooler pane. Coating a glass surface with a low-emittance material and facing that coating into the gap between the glass layers blocks a significant amount of this radiant heat transfer, thus lowering the total heat flow through the window. Low-E coatings are transparent to visible light. Different types of low-E coatings have been designed to allow for high solar gain, moderate solar gain, or low solar gain.

Argon is a naturally occurring, harmless, inert gas that is denser than air. By trapping Argon gas between the panes of glass, it acts as a greater barrier to heat loss and heat absorption in this facility. Filling the space with a less conductive, more viscous, or slow-moving, gas minimizes the convection currents within the space, conduction through the gas is reduced, and the overall transfer of heat between the inside and outside is reduced.

Heat Transfer Basics
Sheathing, insulation, Tyvek... in that order
Insulation Specs
Window Diagram - Heat Transfer
Roof insulation material
A morter net with Insect barrier is set inbetween the brick facade and the tyvek wrap
Fancy Low emissivity argon gas injected windows