2-Hour Fire Protection Walls

These walls can be used on constructions up to four stories in height.

Fire rated separation walls assembly
••• Photo USG

Gypsum area separation walls are a lightweight, non-load bearing partition that provides fire-rated capacity typically used between adjacent walls on townhouse construction. These gypsum separation walls components are steel studs, steel tracks, two layers of gypsum liner panels and aluminum clips attached to the gypsum panel. Gypsum separation walls provide a 2-hour fire protection and also serve as noise reduction between neighboring units. These walls can be used on constructions up to four stories in height and are compatible with standard floor to ceiling heights.

Concept

If a fire occurs in the area, the fire heat will melt the aluminum clips on that side, allowing the burning side wall to separate from the vertical fire barrier member and collapse. At the same time, the vertical fire barrier panel will remain in place supported by the opposite aluminum clips that are not being exposed to the fire. This installation will prevent the fire from propagating to the adjacent wall structure on the other dwelling unit.

Construction

Once the framing has been completed in one of the townhouse units, and before the adjacent unit is framed, at that point is that you will need to start building this wall. Normally a 2-inch thick wall is assembled at least 3/4 of an inch away from the wood framing, allowing for accommodation of the fire-blocking product to be installed between the floor levels.  The separation walls need to be started at the foundation level and must go on all the way to the roof sheathing to form a parapet. The assembly needs to be connected to the framing with aluminum clips which will allow the wall to collapse when the fire exposure on one of the sides affects the framing but will not pass to the other side for a limited time.

Be sure always to verify your building codes for additional requirements and specifications on how to build these walls.

Benefits

Gypsum area separation walls can provide several benefits, including:

  • Thinner profile allows more usable space
  • Ideal for lightweight commercial construction
  • Excellent sound attenuation characteristics
  • Provide STC ratings up to 50-54 when tested in accordance with ASTM E90.
  • Reduce footing structural requirements
  • Meet BOCA and ICBO code requirements for area separation walls
  • Typically are installed floor by floor in the same sequence as building construction
  • Eliminates need for expensive scaffolds systems
  • No additional trades needed for installation
  • Lower cost compared to traditional masonry wall
  • Can be installed under low temperatures
  • Faster installation can be achieved when compared to regular masonry walls.
  • Can achieve a 2 hour fire protection
  • Reduced labor and material costs

Drawbacks

Sometimes it is not feasible to have this walls built, and such cases these are some of the restraints:

  • Gypsum separation walls cannot be used where water and sunlight will have a direct impact on the panel.
  • Openings are not allowed on gypsum separation walls
  • Not intended to be used as shear walls
  • The exterior of these walls shall be protected by weather resistant materials
  • Must avoid contact with materials having high moisture content
  • Exterior wind load is limited to 15 psf
  • Insulation must be installed after building has been properly closed