1980 isolated gain passive solar with sunspace and crawlspace
We are considering purchasing a passive solar home built in 1980 from reclaimed lumber and glass with isolated sunspace. The home is 2 story 1700 sf open floor plan. It has windows on all sides, upstairs have been replaced with newer double pane but downstairs are original. They seem to be 2 panes of glassheld in a frame with very durable adhesive. Sunspace on S side is single pane glass and brick floor w about 1/2 of 5 x 20 sf area taken up by planting bed/soil. The top of it is slanted and is also glass, and had shade cloth on it. Access to about 3 ft. crawlspace is from sunspace. It was open when I saw the home, assume it can be closed. There are windows as well as door that can be opened to let in air from the sunspace. Home appears to be well insulated but current owner does not know R value. Owner spends about $500/yr on propane for heat using a propane stove in NE Oregon. What do you think about the design of this home, and should it be updated or improved, especially. the windows, sunspace and crawlspace? Is there a way to improve on the shadecloth– something more substantial, a different roof for the sunspace? Thanks
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Replies
Susan,
It's impossible to answer your question from the information you have provided. I suggest that you hire an energy auditor or home energy rater (ideally, one certified by by BPI or RESNET) to visit the house and to conduct an energy audit.
Homes built in 1980 were rarely built with attention to airtightness, so there is a high likelihood that the home would benefit from air sealing work.
If the crawl space is connected to the sun space, it's possible that this is a so-called "double-envelope" house, a discredited design that may have high rates of heat loss and possible fire safety issues (due the lack of firestopping in the walls and ceiling assembly).
The shade cloth over the sloped glazing is an indication that the sun space probably overheats during sunny weather. It's always possible to replace sloped glazing with a solid, opaque roof it you want to change the design of the house.
Double-glazed windows are always preferable to single-glazed windows.