DO I NEED A "COOL ROOF"? PART 1

That is the $62,500.00 question! The simple answer is, maybe! Much depends upon the location of your facility. If you live in a cold weather area, where heating is a larger expense than cooling, the answer is probably no, you may not need a "cool roof". However, if you spend more each year to cool your facility than to heat it, a "cool roof" is usually a money saving investment.

Cool roofs are ideal in the Southern and Southwestern areas of the United States. Building owners in these areas can reap major benefits by installing "Cool Roofs". Cool roofs reduce energy cost, increase the lifespan of HVAC equipment, reduce smog, and have lower life cycle costs than other roof systems.

Let's take a look at these issues one at a time. For this post I will focus on the potential Energy Savings.

Reduced Energy Costs. On a typical 90 degree summer day, the surface temperature of a Black EPDM (rubber) roof is over 185 degrees Fahrenheit. That is hot enough to make a nice cup of tea! The most common roof in the Southwest, a mineral surface "CAPSHEET" roof, doesn't do much better at 185 degrees Fahrenheit.

A "Cool Roof", by contrast, will have a surface temperature of 105 -110 degrees Fahrenheit. That is only 15-20 degrees Fahrenheit above the ambient air temperature. Less heat on the roof means that less heat can radiate into the building. Less heat translates to lower energy costs!


So Alex, how much money are we talking about here?

That is a very good good question! Here is an example for a facility located in California:

This facility is a medical office building located in Tarzana, CA. The total roof area is 25,000 sq ft. This is an older building that was built in 1980. The offices are open 5.5 days per week. The existing roof system is an Asphalt Built Up Roof (BUR) system with CAPSHEET surfacing. The building has no roof insulation installed and is heated by natural gas. The HVAC equipment is approximately 5 years old, relatively efficient, and in good condition. For our example the average cost of electricity is 15 cents per KWH, and natural gas is 66 cents/therm. (these assumptions are based upon actual utility company data for the area). Here is what the Building Owners should expect to save per year according to the
Energy Star Roofing Calculator:


ENERGY STAR ROOFING CALCULATOR

Savings Per Year

	Per 1000 sq. ft.		Total
	Qty.	$	Qty.	$
Electricity	2,816.07 kWh	$422.41	70,401.75 kWh	$10,560.26
Natural Gas	-18.59 therms	$-12.08	-464.70 therms	$-302.06
Total		$410.33		$10,258.20

WOW!!! That's $10,258.00 Per YEAR!! If you are already going to replace your roof, this is like receiving free money. In my experience, if a top quality "Cool Roof" system with a 15 year warranty were installed on this facility, it would cost the owners no more than $2.50 per square foot. That translates to a maximum investment of $62,500.00. Resulting in a payback of only 6.09 years! The question that we now have to ask is this: are energy prices likely to increase or decrease in the future? If the past is any indication, energy prices will continue to rise. That means that the payback period could be shorter and the potential savings could be much, much larger.

So there you have it, Cool Roofs save money!! In a future entry we'll discuss some of the other benefits, so stay tuned!!