Roof Ceiling Fire Rating

Ul tests rate an entire assembly.

Roof ceiling fire rating.

You can use only the specific type size and minimum. This is a system test that includes structural members such as beams trusses and roof deck. Urb concealed grid system and tile. Fire tests may be conducted at any one of several recognized facilities.

Where the room side fire resistance rated membrane of the corridor is carried through to the underside of the floor or roof sheathing deck or slab of a fire resistance rated floor or roof above the ceiling of the corridor shall be permitted to be protected by the use of ceiling materials as required for a 1 hour fire resistance rated floor or roof system. However the total depth of the systems with either directly attached or suspended ceiling membranes shall be permitted to extend greater than 36 inches. Ul and fm list many roof ceiling systems in their publications. Don t be left hanging understanding how the nec regards suspended ceiling designs and supports is critical for proper design and installation of electrical wiring and equipment.

The maximum flame spread is 6 feet for a class a rated roof 8 feet for class b and 13 feet for class c. 12 x 24 2 x 4 8 w10 x 25 beam floor units and beam support 3 hr. Time temperature ratings the third major roof system fire test is astm e 119. Both ul and ga include specific guidance regarding the use of insulation in assemblies.

3 4 fr 83 12 x 12 z runners fluorescent type none 2 1 2 concrete. A question has come up concerning sloped roof trusses and fire assembly ratings. The slope of the test specimen is preselected and since steeper slopes are more of a challenge due to melting material feeding the fire the rating applies to the maximum slope passed. Roof ceiling and floor ceiling construction assemblies which are tested and assigned hourly ratings mandated by building codes or other building safety requirements.

Some are reluctant to rely on test results from flat parallel chord trusses applied to sloped roof trusses. In the world trade tower collapse heat load on the connections of steel trusses is suspect. No ceiling or suspension system product alone constitutes a fire rated assembly. Refer to our roof ceiling assembly documents which includes ul fire rated roof assemblies for easy guidance through the assembly of a roof or ceiling on your next project.

As a designer and installer you should know the fundamental differences between a suspended ceiling which is an integral part of a fire rated floor ceiling or roof ceiling assembly and the far more. Concrete with cellular steel 3 hr. Floor ceiling and roof ceiling systems were fire tested at less than 36 inches total depth. Do you have any information regarding the suitability of the fire rated ceiling assemblies for sloped roof trusses.