Our Passive Solar Design

mur_southwestern-adobe-style-home-xThere are many ways to design a custom, sustainable, green, passive solar home. This is a good thing because, it turns out, every customer has their own, unique set of wants, needs and goals. For some people, a custom passive solar home that fits their budget is the most important thing. Others will have extended families under their new roof, or physical limitations or serious hobbies that require custom spaces. Still others have a life long dream to owner-build or owner contract their custom solar home. As custom passive solar home designers, our greatest joy is using our creativity to respond directly to the needs of each of our clients, then watching their excitement and pleasure as the design of their very own, custom solar home begins to take shape.

We began designing super energy efficient passive solar homes in the 1970′s when, we like to say, it was popular the first time. As the idea caught on around the country and more families began living in passive solar homes, those of us in the industry began to hear stories about the passive solar design strategies that worked and those that didn’t. Our founder, Jon Davis, always 20 years ahead of his time, studied the science and listened to the experiences and made it his goal to take passive solar design to the next level. Sunlight Homes began to innovate and over the following decades, Jon developed Sunlight Homes’ approach and philosophy for designing homes that excelled in comfort, energy efficiency, sustainability, livability, and style. Our second generation family business uses his guiding principles to this day.

Rethinking Passive Solar Design

solar-gain-heat-loss-thermal-mass-graphic-Sunlight-HomesTraditional passive solar home plans and designs, with their many south windows, bermed, windowless north sides, trombe walls, clerestories and tons of thermal mass were energy efficient and sustainable, but they were also very expensive and tended to overheat and fade furniture with their enormous south-facing windows. You could identify a passive solar home design a mile away because they had their own architectural look; one that doesn't fit the aesthetics of everyone. There was room for improvement.

The conventional approach to passive solar home plans is illustrated in the diagram with the full circles. Large south facing windows mean more solar gain, but this also means more heat loss at night. This nighttime heat loss requires a larger amount of thermal mass to minimize the temperature fluctuations this situation creates.

With the primary goal of reducing the energy it takes to heat and cool a home, we realized that by reducing the heating and cooling requirements with super insulation and tight construction, it was not as cost effectiveness to design homes with walls of windows and huge amounts of thermal mass. This is not to say it eliminated the need for passive solar design, only that it changed the equation and allowed for more flexibility in design. This means passive solar homes can be designed in conventional architectural styles that don't look "solar".

Structural Insulated Panels (SIPs)

9701-sm.american-clay-walls-french-door-tile-floorIn the late 1970s we found the super insulated building system we had been seeking when we discovered polyurethane structural insulated panels (SIPs). We built our first SIP home at that time and have been building with SIPs ever since.

Today we design passive solar homes in most architectural styles, ranch, Southwestern, Craftsman, prairie, contemporary and many more. We place windows where they are most useful and attractive and on all 4 sides of the home! Every primary, daytime room has abundant day lighting, with light coming in from at least 2 sides. Super insulation and low infiltration means that temperatures are more stable and comfortable year round... naturally. Our new generation of homes are beautiful, functional, healthy and super energy efficient. With small heating and cooling loads, using site generated renewable energy is more cost effective. The smart materials used in the exterior shell insulate better in less space and allow for more pleasing and flexible architectural environments. They are also more cost effective, more comfortable and much more aesthetically pleasing than their 1970s predecessors.

Developing our new approach to passive solar home design allowed us to also incorporate Christopher Alexander's Pattern Language design philosophy and patterns into our design process, which we consider as important as our commitment to sustainable, green architecture. Read more about this further on in this section.

Thoughtfully designed, energy efficient, solar homes are still more expensive to build initially, but they are much higher quality structures, and this is pays back monthly with lower utility bills and greatly enhanced year-round comfort. These are the very things that make our homes a better long-term investment, and a more attractive option for future buyers. Furthermore, living in an ecologically-friendly home helps keep our environment clean and reduces the use of fossil fuels, making a much lighter carbon footprint. We like that.