5 Ways: Improving Roof System Energy Efficiency in Florida
It is that time again. It is the hottest time of year in Central Florida and the sun has been baking the pavement. You know what is coming next. You are dreading getting your latest bill from the electric company. You know the bill will not going down. Most likely the costs have gone up since last year.
When you get the bill and open it up, you begin to think that there must be a way that you can improve the energy efficiency of your building. You need to find some way to put controls in place that will reduce the amount of electric use in the building. As you are sitting back in your office chair you find yourself staring up at the ceiling. And then it hits you! Are there changes that you can make to the roof system may be able to help you control the electric costs for the building?
The roof system represents one of the largest surfaces of the building structure. In fact, if your building is a single story structure there is a good chance that the roof system is actually larger than all of the wall surfaces of the building put together. Addressing the energy efficiency of the commercial roofing system on your building may be part of your solution to controlling the energy costs for your building.
There are multiple solutions for affecting the energy efficiency of your roof system. Here are five solutions that you can implement to help you improve the energy efficiency of your roof system and in turn the entire building structure.
1. Remove Trapped Moisture – Trapped moisture in your roofing system can negatively impact the energy efficiency of the roof. Wet insulation and roofing material has a reduced R-value when compared to dry insulation. Allowing insulation and roofing materials saturated with moisture to remain in your roof system will decrease the energy efficiency of your roof.
Solution – Conduct an infrared thermography scan of your roof system. Infrared scans are a tool that produces thermal images that may indicate areas of trapped moisture. After completion of the infrared scan, the wet insulation should be removed from the roof system and replaced with new dry insulation. After replacement, the roof system is repaired to a watertight condition.
2. Install Reflective Roof Membranes – A low reflectivity rating for commercial roof systems indicates that the exposed surface of the roof system absorbs a high percentage of the ultraviolet rays that hit the surface of the roof. This leads to a build-up of heat and an increase in surface temperatures. Increased surface temperatures on roof systems lead to potential increase in interior building temperature and subsequent increase in electrical consumption in order to cool the building.
Solution – If you have an aged roof system that you are planning on replacing in the near future it is suggested that you replace it with a reflective roof system. If the roof system does not need to be replaced, but needs increased reflectivity then applying a reflective roof coating to the surface of the roof system is an option. Finally, if the roof system is newer but the surface of the roof is dirty then it is recommended that the roof system be cleaned and potentially pressure washed. Dirty roof surfaces can negatively impact the reflectivity of the roof system. If a roof replacement or coating installation is chose, it is suggested that the roof project use an Energy Star rated product.
3. Increase Insulation Values – Reduced amounts of insulation or using insulation with lower R-values in the commercial roof assembly may lead to increased interior temperatures for the building. This may subsequently lead to higher energy bills in order to cool the interior conditioned space. The proper design of a roof system will incorporate insulating products with a higher R-value per inch.
Solution – Increasing insulation values and thickness within your roofing system is a part of the roof replacement process. There are occasions where the savings for replacing the roof system may be a significant reason for completing the project, regardless of the condition of the roof system. A breakeven analysis using energy analysis tools such as NRCA’s Energy Wise Calculator can help analyze potential savings. It is recommended that you work with a professional roofing contractor to evaluate the energy efficiency of your roof system. Core cuts will need to be completed in order to determine the composition of the roof and the subsequent R-value of the overall design.
4. Reduce Fasteners in the Roof Assembly – Many different types of roofs installed today use some type of mechanical fasteners. Depending on type of roofs selected and the design, there can be a significant amount of fasteners in the roof system. Each of these fasteners creates a break in the insulation in the roof system. Fasteners lead to a decrease in the energy efficiency for the roof system.
Solution – When designing a roof system for replacement, it is suggested that you work with a professional roofing contractor to determine if there is an alternative to using mechanical fasteners. Alternatives to mechanical fasteners include the use of non-penetrating fastening systems such as low-rise urethane foam. These types of non-penetrating fasteners eliminate the thermal breaks caused by mechanical fasteners and improve the energy efficiency of the roof system.
5. Reduce Ponding and other Drainage Issues – Roof assemblies are designed to have positive drainage and are not built to retain moisture. Water retained on the roof system increases roof surface temperatures because the water retains the heat from the sun’s rays. In addition, ponding promotes organic growth on the roof system leading to reduced reflectivity and increased heat build-up.
Solution – If there are ponding water conditions on the roof system, address those isolated areas by installing a new roof drain or potentially installing tapered insulation to promote drainage. However, there may be situations where the ponding water conditions are excessive. If there are situations where moisture is excessive and isolated solutions will not work, a full roof replacement may be necessary. If roof replacement is required, it is suggested that a professional roofing contractor design a tapered insulation system to provide complete drainage to the roof system.
Addressing the energy efficiency of the commercial roof system on your building may be a great opportunity for you to begin looking at controlling the energy costs for the building. As you can see there are simple solutions and more complex solutions that you can implement to help you reduce the energy consumption of your building. A professional roofing contractor can work with you to help you evaluate the energy efficiency of your roof system and make suggestions on how to improve the roof system’s performance.