(10/3/2008) ICFs Keep Greensburg on the Road to LEED Platinum
Greensburg, KS — On the night of May 4, 2007, 95% of the homes and businesses in Greensburg, Kansas were destroyed by a massive EF5 tornado that was nearly two miles wide. Although this storm was devastating to the entire community, its rebuilding has presented Greensburg residents with an unparalleled opportunity to create a ‘green’ city from the ground up.
The Greensburg city council recently approved a resolution that all city building projects will be built to LEED Platinum level standards. Platinum is the highest level of LEED certification, and Greensburg will be the first such city in the US.
Janek Dombrowa, principal architect of JTD architects in Los Angeles, is spearheading much of the architectural design for the Greensburg rebuild. He is also a professor at the University of Southern California. Dombrowa was approached by the Discovery Channel to become involved with Greensburg by conducting research about sustainable design.
Dombrowa has been holding discussions with the Greensburg planning board to encourage them to use ICFs on the majority of the projects for their inherent energy efficiency and high strength. Many of the residents have had to rebuild their homes more than once due to tornadoes. They typically rebuild using conventional stick framing, which is not as strong as ICFs.
“Tornadoes aren’t the only concern when rebuilding,” said Erich Brandt, Senior VP of Sales and Marketing for ACH Foam Technologies, the manufacturer of the ICFs. “The buildings must also withstand damage from flying debris due to the tornadoes. ICF systems are able to better withstand the battering of flying debris. For example, while a small 2 x 4 propelled from a tornado can easily penetrate a wood or brick stick framed home, an ICF-built home will withstand the impact,” explained Brandt.
Laboratory testing at the Wind Engineering Research Center, Texas Tech University, compared the impact of residential concrete wall construction to conventionally framed walls. A 2 x 4 stud was propelled at 100 miles per hour at various wall specimens, the equivalent weight and speed of debris generated during a tornado with 250 mile per hour winds. The wood framed walls failed to stop the penetration of the 2 x 4 wood stud, while the insulated concrete forms successfully demonstrated the strength to resist the impact of debris propelled at high wind speeds.
Wall Type
|
Test Wall
Description
|
Speed of Debris
|
Results |
Wood Frame
|
2 x 4 wood studs at 16" o.c., 3-1/2" batt insulation,
5/8" gypsum board interior finish, vinyl siding over 3/4" plywood
sheathing exterior finish
|
109.0 mph
|
The debris "missile" perforated assembly. Little
damage to the missile.
|
|
2 x 4 wood studs at 16" o.c., 3-1/2" batt insulation,
5/8" gypsum board interior finish, 3" brick veneer with 1" air space,
over 3/4" plywood sheathing exterior finish
|
69.4 mph
|
The debris "missile" perforated completely through
the brick veneer and interior finish. Minor damage to the missile.
|
Steel Frame
|
Steel studs at 16" o.c., 3-1/2" batt insulation, 5/8"
gypsum board interior finish, vinyl siding over 3/4" plywood sheathing
exterior finish.
|
103.5 mph
|
The debris "missile" perforated completely through
the wall assembly. Little damage to the missile.
|
|
Steel studs at 16" o.c., 3-1/2" batt insulation, 5/8"
gypsum board interior finish, synthetic stucco over 1/2" gypsum board
sheathing finish.
|
50.9 mph
|
The debris "missile" perforated completely through
the wall assembly. No damage to the missile.
|
Insulated Concrete
Form
|
Block ICF foam forms, 6" thick flat concrete wall, #4
vertical reinforcement bars, 12" o.c. vinyl siding. (Tested a second
time with similar results).
|
103.8 mph
|
Debris penetrated vinyl siding and foam form. No
cracking, front face scabbing or back face spalling of concrete wall
observed.
|
|
Block ICF foam forms, 6" thick flat concrete wall, #4
vertical reinforcement bars, 24" o.c. 3" brick veneer with ties spaces
1' o.c. each way.
|
99.0 mph
|
Debris penetrated and cracked brick veneer. Foam
form dented. No cracking, front face scabbing or back face spalling of
concrete observed.
|
|
Block ICF foam forms, variable thickness "waffle"
concrete wall, 6" maximum thickness. #4 vertical reinforcement bars in
each 6" vertical core at 24" o.c. Synthetic stucco finish. (Tested a
second time with similar results).
|
100.2 mph
|
Debris penetrated synthetic stucco finish and foam
form. Impact of wall at 2" thick section. No cracking, front face
scabbing or back face spalling of concrete wall observed.
|
|
Panel ICF foam forms, 4" thick flat concrete wall, #4
vertical reinforcement bars, 24" o.c. vinyl siding.
|
96.7 mph
|
Debris penetrated vinyl siding and foam form. No
cracking, front face scabbing or back face spalling of concrete wall
observed. |
IntegraSpec sponsored Executive Manager Nicholas Nikiforuk’s residency in Greensburg to work with architects and engineers building the new ICF housing for the crews. Nikiforuk, a certified commercial IntegraSpec installer, spent two months in Greensburg working 12 to 16 hours a day to help with the new ICF commercial building. According to Nikiforuk, IntegraSpec has incorporated several unique design features into the ICF wall system that make installation easier and solve design challenges faced by architects, engineers and builders.
Nikiforuk added that Greensburg’s city council is in the planning phase for many of its buildings. IntegraSpec, an award winning ICF company, has partnered with leading expanded polystyrene (EPS) manufacturer ACH Foam Technologies to mold the ICFs that will be used in Greensburg to rebuild the town1. “At this time, ICFs have been specified by architectural consultants for a light commercial building that will be used as temporary housing for the crews and volunteers,” said Nikiforuk. “IntegraSpec ICFs were chosen for their ability to satisfy the project’s design challenges and LEED standards.”
“The IntegraSpec product has an interlocking web system that eliminates form lift, a girder truss insert that eliminates form compaction, and a unique insulating window buck system that makes framing out rough openings for windows and doors fast and efficient. The result is a thermal EPS building envelope,” added Nikiforuk.
ACH Foam Technologies has been a leading manufacturer of EPS products for over 40 years. LEED awards credits for EPS because of its stable R-Value without thermal drift, compliance with energy codes, dimensional stability, recycled content and proximity of plants to delivery points. EPS manufacturing uses minimal energy and creates very little pollution. Steam is a component of the expanded polystyrene (EPS) manufacturing process. The water from this process is collected and re-used many times.
LEED Credits for ICFs
Energy & AtmosphereCredit 1 – EPS provides a stable R-Value without thermal drift, ensuring long term performance
Credit 2 – EPS helps ensure compliance with local energy codes and ASHRAE 90.1-1999
Materials & ResourcesCredit 1 – EPS is dimensionally stable and can be reused during building renovations.
Credit 4- EPS is made with up to 15% recycled content
Credit 5 – ACH Foam Technologies has many plant locations across the US. A plant is likely to be within 500 miles from the jobsite
1 IntegraSpec ICFs, a proprietary product of Phil-Insul Corp., are manufactured by ACH Foam Technologies.
ICF Benefits
• Superior Strength – Resists wind loads, including hurricanes and tornadoes.
• Provides Durability – Protects against rot, decay, corrosion and termites.
• Code Listed
• No Special Engineering Required
• Fire Resistant Wall
• Less Scaffolding
• Less Bracing
• Eliminates Stripping, Form Oil Release Agents & Cleaning Forms
• Ability to Pour in Cold Weather
• High-R-Values – No Thermal Transfers or Air Leakage
• Contain no CFC, HCFC and HFC or other ozone depleting blowing agents
• Inert, non-nutritive, and highly stable
• Will not decompose or decay
• Will not produce undesirable gases or leachates
• 100% Recyclable
• Safe for WTE Systems
• Recommended Component of LEED Certified Projects
About ACH Foam Technologies & IntegraSpec
For more information about EPS and ICFs visit
www.achfoam.com or call ACH Foam Technologies at 800.638.3626. Leadership in Energy and Environmental Design (LEED) is the nationally accepted benchmark for design, construction and operation of high performance green buildings. Owners of LEED buildings receive tax incentives for reducing the environmental impact on their surroundings. Consult LEED (
www.usgbc.org) for more information about credits and tax incentives. IntegraSpec is a registered trade mark of Phil-Insul Corporation (
www.integraspec.com).