AUSTIN CLIMATE HISTORY SPECIAL PROBLEMS
Austin has a total area of 258.4 square miles 251.5 square miles is land and 6.9 square miles (2.67%) is water. The city is situated on the Colorado River with three man-made (artificial) lakes within the city limits:
CLIMATE
Austin has a humid subtropical climate characterized by hot summers and mild winters. The highest recorded temperature was 112ï½°F on September 5, 2000. Austin is usually sunny and at the least partially sunny.
During springtime, severe thunderstorms sometimes occur and portions of the city are frequently subjected to flash floods. Central Texas is often called “Flash Flood Alley” because of its frequent, intense storms. Although it is common to have tornadoes in Texas, they are kind of rare in the immediate Austin area. You are much more likely to be killed by lightning than a tornado.
As of the census of 2000, there were 656,562 people, 265,649 households, and 141,590 families residing in the city (roughly comparable in size to San Francisco, Memphis and Columbus). The population density was 2,610.4 people per square mile (1,007.9/km)
HAIL STORMS OCCURRING IN THE AUSTIN AREA
According to Insurance Council of Texas, the hail storm that occurred on March 25,2009 was the worst and most expensive hail storm on record. Estimates are in the range of $160 Million and still increasing as claims are continuing to be filed. 22,000 vehicles were damaged and 15,000 homes received insured losses. There were golf ball to tennis ball sized hail from Burnett County to Travis and Williamson Counties.
CLIMATE ZONES FOR ROOF SYSTEMS
Climatic conditions vary considerably over the United States forming similar climatic divisions which when grouped together form climatic zones. The National Oceanic and Atmospheric Administration (NOAA) defined these regions within a state that are as close to the same climatic condition as possible. Each NOAA Climatic Division is placed into one of five climate zones. Based on its 30 year average heating degree-days (HDD) and cooling degree-days (CDD) for the period from 1971 through the year 2000. This database is continually updated. Based on this knowledge, roofing materials for the specific climatic zones are recommended by the manufacturers. The Roof Guys are taught these technical recommendations and hold to these standards when applying your roofing systems.
MAP OF CLIMATE ZONES
Climatic problems that affect roofing systems most are:
- Hail
- Wind
- Lightning
- Sun/UV
- Extreme Temperatures
- Fire
CLIMATE/ROOF SYSTEM
Different regions of the United States are subject to different weather patterns. As such, each region has special roofing requirements that you must be sensitive to either in the industry or as a homeowner looking to roof repairs or replacements.
There are five primary roofing materials approved by the Institute for Business and home Safety:
Tile become brittle as they age and ultimately need replacing they are prone to developing cracks. As water gets into the cracks, the liquid freezes and then expands, causing the tile to break. A tile roof is also rather heavy. Though tile is a reasonable roofing material for areas with a lot of moisture or very cold winter should take into consideration the weakness of this material.
Metal roofing is especially popular for low or steeped roofs. This is so because there are no shingles, therefore the slope of the roof is not an issue. Although metal roofs can receive cosmetic damage from hail, you can buy metal product which is rated for high impact. Additional to the ability to resist damage caused by hail, metal roofing is highly fire resistant. In areas prone to brush fires like the South west United States metal roofing is required for all buildings abutting the tree line. Metal roofing is not without its disadvantages though, as it is two to three times as expensive as asphalt.
Asphalt shingles reinforced with fiberglass are relatively low cost, easy to install and are highly resistant to fire. They should be used in regions where hailstorms occur. Asphalt shingles have wind warranties of up to 130 miles per hour available. Properly installed, shingles could survive 15 to 25 years. High-end asphalt shingles can come with 50-year warranties.
Slate outlasts just about every kind of roofing material. It is so strong that hail would have to be the size of cannonballs to put a dent in it. It is also the most expensive roofing material. Slate roofs require special care and attention, and slate qualified roofers to make repairs and replacements. A downside of slate is that it is incredibly heavy as it is a naturally occurring stone. The underlying structure of the roof must be able to hold the weight of the stone.
Wood is good in dry climates, although it can suffer a lot of damage in hailstorms and, unless it is treated with a retardant at the factory, it is not fire-resistant.
