Draftstopping Partition Attic Detail

Multi unit housing projects are often draftstopped at specific intervals to prevent fire from jumping between adjacent units via a common attic space.

Draftstopping partition attic detail.

Openings in the partitions shall be protected by self closing doors with automatic latches constructed as required for the partitions. Fireblocking shall be provided in concealed spaces of stud walls and partitions including furred spaces and parallel rows of studs or staggered studs as follows. Vertically at the ceiling and floor levels. If a fire rated assembly rather than draftstopping is required within concealed attic spaces the following details show approved one hour and two hour rated assemblies that may be used in the roof cavity and that may be constructed with gable end frames or trusses.

1 if there is no useable space above the assembly an attic or below it a. Figure 17 3 3 ul u338 1 hour rated wall bearing or non bearing with. Must extend to the underside of the roof sheathing draftstopping materials must not be less than o 0 5 inch gypsum board o 0 375 inch wood structural panel. Draftstopping is used to subdivide flooring at specific intervals and in attics and crawl spaces.

Draftstopping materials shall not be less than 1 2 inch 12 7 mm gypsum board 3 8 inch 9 5 mm wood structural panel 3 8 inch 9 5 mm type 2 m particleboard or other approved materials adequately supported. In combustible construction nearly all the codes specify that lumber or wood structural panels may be used for this purpose. Draftstopping in floor ceiling spaces and attic spaces shall comply with sections 718 3 and 718 4 respectively. O draftstopping must be installed to subdivide concealed combustible attic spaces into areas not exceeding 3 000 sq ft draftstopping materials must comply with the following.

Openings through these partitions whall be protected by self closing doors of the same thickness and materials as the partition. Draftstopping shall be provided in attics mansards overhangs or other concealed roof spaces of group r 2 buildings with three or more dwelling units and in all group r 1 buildings. Some codes include other draftstopping materials such as gypsum board cement fiber board or particleboard. Draftstopping where useable space is both above below concealed space of floor ceiling assemblies concealed space not to exceed 1 000 sfon each side of draftstop approximately of equal sizes there are some points to be made about the draftstoppingrequirements.