To avoid wind and windborne debris damage to rooftop ductwork it is recommended that ductwork not be installed on the roof see figure 5.
Seismic roof curb detail.
The goal is to match or exceed the seismic roof curb design value referred to as the ss value.
Any roof curb rigid or vibration that have been engineered and stamped to meet current ibc 2015 you may also hear this as complying or calculated.
The width of the supporting structural steel shall be at least as wide as the base plate of the curb.
The curbs should be anchored to structural steel concrete as fallows.
Flat or sloped.
Seismic curbs see figure 12 seismic curbs are available on a special quoted basis.
If the roof curb will be mounted on a new building it can be assembled at any convenient location and installed as soon as the roof support members are in place.
Bolts should be with nuts and washers.
Bolts should be placed in every hole provided in the base plate of the curb.
Curb must be capable of supporting seismic loads of two options.
We ve built more curbs than anybody relying on years of experience and libraries filled with hvac equipment data.
Ss is the mapped maximum credible earthquake five percent dampened spectral response acceleration parameter at short periods as defined in asce 7 10 section 11 4 1.
Additionally seismic requirements are not fulfilled by just ordering a seismically stamped roof curb.
Front inlet height top bottom rear outlet length.
Seismic roof curb seismic roof curb detail.
Become familiar with the roof curb installation procedures.
If ductwork is installed on the roof it is recommended that the gauge of.
Up to 0 75gs up to 2 06gs curb heights vary in increments of 4 00 from 14 00 to 34 00.
It is comprised of fully welded galvanized steel and ships ready for jobsite installation.
Founded in 1959 and with 5 factories across the country thybar is the oldest and largest roof curb manufacturer in the world.
The attachment of the curb itself also needs to be designed and specified.
Curbs solidly braced or bolted directly to the building structure without vibration isolation.
The src is a seismic wind load rated roof curb engineered for installation in earthquake prone and or high wind areas.
Additional roof curb anchoring and methods of securing equipment to the curb are also a requirement and must be adhered to for the certification to be valid.
The additional requirements are detailed on each stamped submittal drawing.
Use tack welding or other suitable fastening.
As a general rule the curb should be placed directly on the roof support members.
