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Summer Shade Southern CypressOrientation of the South Wall: Custom Energy Specs that are a part of sun-inspired home designs include recommending an orientation as part of the provided services. In conjunction with the latitude, climate, details of each plan and the customer’s preferences, a recommended orientation is provided.  Orienting the home a little to the southeast so that the south wall of home is in the shade by mid-afternoon in summer is a common recommendation that results in little winter heating penalty.
(The green house at the top of the newsletter shows the entire south wall of the home in shade late in the afternoon as would be the case with a slight easterly orientation.)

South Overhang Length: Ideally, overhang lengths should allow for full sun in the winter from 9:00 a.m. to 3:00 p.m. on the Winter Solstice and full shade on the Summer Solstice during the same time period. This varies based on latitude, climates and the particular roof to wall overhang detail as well as wall and window heights of each design.
(The photo here shows the shade line for a home in a warm climate extending past the bottom of the window to allow for an extended shading season in summer.)

Casement and Shaded Porch 2Shade east and west windows:  Porches and trees placed on the east and west sides of homes keep the intensive morning and afternoon sun off of both the glass and the house!
(Note the shade line across this west-facing porch.)

Passive Cooling:  Where the night temperatures drop below 68 degrees F, some home owners find passive cooling desirable in summer – or at least during late spring and early fall with some of the following window strategies:

– Windows and doors on opposite sides of rooms increase cross breezes
– Casement windows have a greater operable area when open AND scoop air with out-swinging windows which increases air flow.
– Opening windows on both upper and lower floors (including daylight basements) increases the stack effect of passive cooling which again increases air flow.
(The photo above shows a casement window open 90 degrees to the wall.)


The Sun-Inspired House
(including the new electronic PDF version) has much more information about sun-inspired design.

The Sun-Inspired House Book Cover

The Sun-Inspired House Book Cover

If you want to learn about the benefits of a passive solar home and how to approach the custom design and building process, you might want to pick up a copy of my book, The Sun-Inspired House.

The book covers the underlying principles of using sun and light to energize a home and the prerequisites involved in a sustainable or green design. With information on selecting and working with a builder, a primer on energy analysis and rating systems, and over 50 sun-inspired designs to peruse, this book is an excellent source of information for anyone considering building a passive solar home.

One of my favorite energy writers, Martin Holladay, wrote a very honest review of the book last summer comparing it to other popular books on passive solar. See more about him and the review in “Musings of an Energy Nerd.”

In October, tour a Sun Plans sun-inspired home in eastern North Carolina.

Watch for the American Solar Energy Society (ASES) National Solar Tour near you! It features active solar tours with some passive solar and green building at various sites throughout the U.S.

If you are near Greenville, NC (eastern), in October 2009, check out one of our clients who are showing their Sun Plans’ Solstice home.

The home, designed by Sun Plans Inc., is named the “Solstice” and images of this an be found at http://sunplans.com/html/houseDisplay.php3?house=Solstice&page=photos.ASES Solar tour_logo

6-21-09-ss-1The Summer Solstice is here! And so are the long hours of daylight, the deep green trees, and the brilliant flowers. Cool rivers and ponds are beckoning and so are our porches and decks that allow us to enjoy these views.

In the design stage, we have clients asking for the same attention to detail for the outdoor spaces as they do the indoor. After all, many have carefully selected their land for the magic that the natural elements possess.

Since the sun is rising far in the northeast and setting far in the northwest, porches on the east and west can be especially delightful right now. But even north porches or decks capture a few sunbeams this time of year.

These same porches can also shade the east and west house walls and windows. This reduces solar gain from the intense east and west sun this time of year. Even the north windows of the home receive a few sun rays beaming in during the earliest and latest part of the days. Personally, I love these surprise sun rays streaming into the house that remind me of the sun’s movement. It’s also one reason why we do not recommend a porch across the entire north side of a home.

The south windows of a home will receive surprising little direct sun since the great ball of fire is so high in the sky at noon. (To be specific its is almost 47 degrees higher than it was on Dec 21.) Actually,with a properly designed south overhang above south-facing windows, there should be no sun entering the house from 9 a.m. to 3 p.m. But as the sun begins to drop back down in the sky (or actually as the northern hemisphere of the earth begins to tilt away from the sun), the south windows will begin to receive a little more sun daily. Designing for the middle of summer can be one of the biggest challenges in passive solar design and why even with our sales of pre-designed or stock plans, we look carefully at the location in which the house will be built and sometimes make recommendations to modify the design for maximum comfort year-round.

http://www.sunplans.com/html/home_page_2.php3