Use the psychrometric chart to plot a specific climate area for analysis.
Plot the daily temp. cycle for an average day of each month.
Daily loop is almost always the same shape and angle because the temp. and the relative humidity (RH) are inversely proportional to each other (high temp. results in low RH, low temp. results in high RH).
Peak temp. is around 3 or 4 in the afternoon.
Peak relative humidity (RH) coincides with the minimum temp. at 4 in the morning. Doesn't mean moisture has been added to the air just that the same moisture content represents a higher percentage of saturation at the lower temp's.
100% RH = when air temp. drops below the temp. at which saturation occurs, the moisture will condense out as rain or dew.
dew point temperature = the temperature of a given moisture content at which saturation occurs.
Cold Climate:
Rare in the U.S., occurrences are Alaska and North Central plains states.
Capture daytime temperatures and seal the building at night.
Minimize exposed building surface area, enclose as much volume in as little envelope as possible
Enclosing all the volume in a single skin
Evergreens in a row to block prevailing winter winds, they will shield objects downwind for a distance of 3-5 times the height.
Fireplace at west end of a residence.
internal or external vestibule preventing the escape of internal heat.
Temperate Climate:
Most of United States is temperate, too cold in winter or too hot in summer.
Use air movement, solar input to boost MRT and proper insulation to solve both problems.
Building shape = longer in east to west direction making south facade longer for better solar gain.
Porches to the south or awnings on the windows.
Large deciduous trees on south or west, providing shade during summer and losing leaves for winter allowing solar gain at that time.
Evergreens to the North if there is wind from that direction.
Hot Humid Climate:
E.G. Houston, Texas
Out of comfort zone due to humidity level
Insulation provided no help until there was air conditioning
Allow the greatest amount of air circulation as possible in order to dissipate heat as quickly as possible.
Possibly detached kitchen.
Utilization of exterior passageways, balconies or breezeways.
roof with two separated layers or open gable to release hot air.
Southern homes use a central stairwell and have open windows at the top
thermosiphoning = using convection to suck fresh air through the building
keep brush clear of windows for best possible ventilation
palm trees are useful for best shading and allowance of air flow.
Hot Arid Climate:
This climate typically shows the greatest daily variations. E.G. Phoenix, Arizona
Large diurnal (day to night) temperature swings due to typical clear skies.
Large radiation losses at night from building and surrounding environment
Capture and store energy in the building
Heat can be "used up" by the evaporation of water. E.G. Fountain in a courtyard house with no window openings below approximately four feet and an enclosing wall and door. the air is dry enough so that the evaporation within the building compound can bring down the temp. quite significantly.
Building material, use high thermal mass materials like adobe, rammed earth, etc., they absorb the heat and release it slowly at night as well as cool at night for the following day
Courtyard houses have openings to the courtyard, windows on outer walls are small and higher on the wall,
heated air escapes, cool air stays in.
psychological effect, sound of fountain and quiet courtyard cause a cooling and calming environment even if temp. doesn't change.
time: 1.0, 7:15-7:30,8:00-8:45pm 6/14/09
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