Benefits of Building with Metal in Retrofits White Paper
Available from The Metal Initiative
The Metal Initiative has produced a white paper focusing on using metal in retrofit applications. With retrofit being one of the hottest topics in the institutional and commercial building industry today, the white paper addresses the reasons why building owners, developers, and architects are and should be choosing metal. Metal's benefits are more than economical and environmentally friendly; they're also visually appealing and long lasting.
The Metal Initiative's white paper outlines the financial and environmental advantages of retrofitting with metal roof and wall systems. For architects, contractors, and business owners the paper explains how to improve building appearance, and reduce long-term energy costs by using metal in retrofit projects.
The following benefits, versatility, and applications of using metal are highlighted in the report:
Existing Building Solutions
For more than 25 years, retrofit has been a quick, cost effective solution for problematic roof geometry, maintenance issues and outdated appearance. In more recent years, thermal efficiency and energy savings are the hallmarks of a retrofit roof application.
As building owners become more involved in energy and environmental issues they are finding greater benefits from retrofitting roofs with metal. In addition to being aesthetically pleasing, metal is a sustainable material that is made from recycled materials and is fully recyclable. Metal also has reflective and emissive benefits, so it reduces heat gain and the building's carbon footprint. It may also add points in seeking certification under the USGBC's LEED building guideline program. Installing a retrofit system typically does not require removal of the existing roof or wall material so it also reduces landfill waste...
Roofing Applications
The most common retrofit applications are metal over existing flat roofs and metal over existing sloped roofs. Both of these improve a building's appearance and reduce maintenance, but each can offer solutions to different problems.
All retrofit systems are fully engineered. From the design phase through completion of installation several steps must be taken to ensure the integrity of the system and the project...
Existing Flat or Nearly Flat Roof Solutions
The two common types of retrofit installations on existing structures are low slope and steep slope roofs. During installation of either of these types of retrofit systems the building interior is not exposed to outside elements or contamination from construction.
Low slope installations are usually utilitarian and economically driven. A variety of framing methods can be used to turn a flat roof into a new roof sloped with a pitch from 1/4 to a maximum of 2:12. Typically a low slope application does not add curb appeal but is designed to improve discharge of rainwater...
Rooftop Equipment
A key consideration in designing a retrofit system for flat roofs is location of the rooftop equipment. Typically this involves air handling and non-air handling equipment for heating and air conditioning systems, as well as skylights, sanitary vents, exhaust fans, and fresh air intakes. How this equipment fits into the retrofit is up to the designer, but the location of existing equipment usually dictates what can be done.
The first option may be to roof over the existing equipment. This will be determined by first evaluating all aspects, including required exhaust needs. Another option is to relocate the air-handling units above the new roof plane. If this is the desired application, a structural support system must be engineered to accommodate the weight of the existing equipment. In addition, new air handling ductwork will have to be installed from the relocated unit to the existing roof penetration. It is recommended to only use curbs approved by the new roof manufacturer...
Existing Sloped Roof Solutions
Designing retrofit systems for sloped roofs requires attention to many of the same details in the design stage as for flat roofs. These include analyzing the existing roof support system and using the opportunity to improve ventilation systems and insulation levels, and potentially adding renewable energy systems to the design.
In sloped roofs it also is important to determine the necessary wind uplift performance so that the system meets applicable building code requirements. Both metal and conventional sloped roofs can be retrofit with metal roof systems...
Energy Efficiency
The retrofit process offers some excellent ways to improve a building's energy efficiency and help reduce its carbon footprint. By adding a few low cost elements to the retrofit system the designer can help the building owner realize significant savings.
These elements can include extra insulation for improved thermal resistance, installation of a radiant barrier and the creation of more ventilating space. Another consideration in designing the retrofit system is to use solar technologies to add thermal heat-recovery or power systems.
To read the entire White Paper, visit www.themetalinitiative.com. You'll see why building with metal makes sense.
The Metal Initiative is an industry-wide program to educate owners, architects, and contractors about the use of metal in building construction. Visit www.themetalinitiative.com for informational and educational resources to help you get more building for your money.
Information courtesy of The Metal Initiative |
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