I am in the process of designing a passive solar home.
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I would like to use modular technology to keep my initial building/framing costs low. My understanding is I need thermal mass in my floor but the modular people often need to build a stick floor system. Want to marry the modular efficiency with the passive solar energy concepts.
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Some modular manufacturers offer tile or other masonry floor finish options, or they can prep a floor to accept such finishes. But there' s a lot more to passive solar design than just additional thermal mass.
Cutting corners on the building envelope is often penny wise and pound foolish. There is only so much sun available at any given location, but reducing the design heat load of the house with a quality envelope increases the relative proportion of heat that is available for free from the sun.
It's not just about letting the sun in, but also about keeping the heat from leaking out. A high-quality, highly-insulated and air-tight envelope is the starting point for a well-functioning and cost-effective passive solar home.
After that, proper orientation and solar exposure, hight solar heat gain windows on the south, appropriate overhangs or other summer shading provisions, adequate but not excessive thermal mass in direct sunlight, open floorplan for even heat distribution - these are equally important elements of passive solar design.
There are no shortcuts to an efficient, comfortable, durable house.
Thank for you answer. I have all of the additional components you mentioned in the design in the last paragraph. You can have too much thermal mass? What about a wood floor system that has a 2" concrete floor poured on top. Some people have mentioned this. Can this be a way to achieve thermal mass in the floor? I plan on creating thermal mass in the walls as well if necessary. I know there is an equation for the proportion of glass to thermal square feet of flooring and will take this into consideration. I just want the modular stick part of a structure and will take it over from there with the appropriate glazed windows for each side, blown in insulation, etc. jDo you know of any modular passive solar companies in the Northeast? Thank you in advance for your answers.
Robert has laid out very well the considerations in building a passive solar home, a highly efficient building envelope is priority # 1. My experience as a builder tells me you should start from scratch on this project and consider building this home on site. I think you will find too many compromises have to be made in trying to marry the modular home with the passive solar concept.