When designing a passive solar dwelling, it is important to keep in mind location. Climate, wind, sun exposure and many other factors determine good guidelines for passive solar construction. For now, we are going to take a look at Texas as the construction area, so the following tips are related to that area only.Texas has a warmer climate, and frequently has higher humidity. Due to these factors, cooling measures are more important and more difficult to achieve. Try to avoid carpets, drapes and overstuffed furniture when possible. They will absorb moisture and make occupants feel clammy.• The optimum building shape is long and narrow, with the longest sides facing south and north.• There should be minimum glazing (glass or other see through materials) on the east and west. The sun strikes these surfaces at least half of the day and cannot be easily controlled. The most glazing should be on the south side with a moderate amount on the north.• Use sizable overhangs on the south side to provide shade in the summer and allow sun in the winter.• For passive heating, direct gain, thermal mass materials should be used on the interior, such as masonry floors and walls.• For passive cooling, shading is the most important. The more outside shade, the better.• Highly reflective exterior surfaces can direct a large part of the suns heat away from the structure.• Use natural ventilation. Casement windows can be opened 100 percent, so they make a good choice.As you can see, there are many considerations to be made, and this is not nearly all of then. It should, however, give a starting place for more in depth research.