Attic Draftstopping Details

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.

Attic draftstopping details.

Multi unit housing projects are often draftstopped at specific intervals to prevent fire from jumping between adjacent units via a common attic space. In past years confusion in this area often led to change orders adding attic sprinklers to nfpa 13r systems. Draftstopping is also still required in the attic. If the assembly isn t concealed an open floor ceiling assembly above a basement draftstopping isn t required.

Attic draftstopping evaluation final report page 6 thus there is precedence to allow five story pedestal buildings with nfpa 13r sprinkler protection and no sprinkler protection in the attics. In combustible construction nearly all the codes specify that lumber or wood structural panels may be used for this purpose. There are some points to be made about the draftstopping requirements. 1 if there is no useable space above the assembly an attic or below it a.

Draftstopping is used to subdivide flooring at specific intervals and in attics and crawl spaces. So even where nfpa 13r would allow the omission of attic sprinklers sprinklers might be provided to eliminate the need for attic draftstopping. Draftstopping similar to fireblocking draftstopping is installed to prevent the movement of air within open building areas and is most often installed in crawl spaces attics and floor assemblies. Draftstopping shall be installed above and in line with sleeping unit and dwelling unit separation walls that do not extend to the underside of the roof sheathing above.

The babcock davis draft stop door is a non rated access door designed to provide access through draft stop spaces in the attic while preventing a back draft from one section of the attic to another. 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. If there is no useable space above the assembly an attic or below it a crawlspace draftstopping isn t required. Some codes include other draftstopping materials such as gypsum board cement fiber board or particleboard.

Figure 17 3 3 ul u338 1 hour rated wall bearing or non bearing with.