Lightweight Concrete Roof Fire Rating

Concrete masonry is widely specified for fire walls and fire barriers because concrete masonry is noncombustible provides durable fire resistance and is economical to construct.

Lightweight concrete roof fire rating.

Chapter 7 of the international building code ibc refs. 38 mm is required to minimize the cracking that can be expected during the curing process. 1 inch 25 4 mm 1 pound per cubic foot 16 02 kg m3. The westford ma based national roof deck contractors association has published guidelines for rehabilitation of old gypsum decking.

Typically the code may require a one to three hour fire rated roof system for protection of life from interior fires. Normal weight or lightweight concrete. Criteria for coreslab to carry a 2 hour fire rating is found in chapter 7 of the international building code 2000 sections 703 3 and 720. Coreslab hollowcore plank by coreslab carries a 1 hour fire rating in all applications by passing the test requirements set forth by astm e 119 as performed by u l.

Lightweight insulating concrete is also considered non combustible and nailable. 1 normal weight 147 153 3 1 2 1 1 2 normal weight 147 153 4 2 normal weight 147 153 4 1 2. Fire resistance ratings of two wythe concrete walls for si. Fire resistance of two layer concrete walls floors and roofs.

Fire endurance of structures figure 5 shows the effect of fire on the resistance of a simply supported reinforced concrete. Many buildings require an hourly fire rating as part of build ing code mandated designs. Structural function or both. The duration of time that an element such as beam column wall floor or roof can endure.

2 3 governs materials and assemblies used for structural fire resistance and fire rated separation of. This involves the ability of concrete structural element to continue perform a specific structural function or confine fire or both. The rn0 59 value for one 1 2 to 3 1 2 airspace is 3 3. Fire resistance of concrete is the ability of concrete to withstand fire or to give protection against fire.

Dry unit weight of 35 pcf or less and consisting of cellular perlite or vermiculite concrete. The light weight is achieved through use of expanded aggregates such as perlite or vermiculite air entrainment or both. Fire resistance rating or fire rating is defined as the duration of time that an assembly roof floor beam wall or column can endure a standard fire as defined in astm e 119 3. Lwic systems can achieve a real cost savings of 1 00 to 1 50 per square of roof area for 1 1 2 hour or higher.

Assembly rating hr concrete type concrete unit weight pcf concrete thkns in. Lightweight concrete the second choice for achieving a one hour fire rating in most ul designs is to pour lightweight concrete directly to the wood subfloor. Because lightweight concrete shrinks when it cures a minimum of 1 1 2 in. Bxuv d949 fire resistance ratings ansi ul 263 7 5 12 8 32 am.