Approved Document B Volume 1

Approved Document B Volume 1

1. B3 Protection if Openings and Fire-Stopping

   • Section 7 - Protection of Openings and Fire-Stopping
     • Openings for Pines
       • Proprietary Seals = has been shown by test to protect walls, floors and cavity barriers.
       • Pipes with a Restricted Diameter = fire stopping to be used around pipe to keep opening as small as possible
         • 160mm or smaller depending on circumstance
       • Sleeving = Non-combustible pipe can be used as a sleeve around a smaller lead, aluminium, aluminium alloy, fibre cement or uPVC pipe.
     • For a fire protecting element to be effective the area should be adqeuatley sealed ot fire stopped
     • Ventiliation Ducts, Flues etc.
       • Where circulation is occuring in a dwellling house taller than 4.5m need to comply with 2.16
         • If it passes through a compartment wall check B Volume 2
       • If a flue/duct contains flues/ducts and passes through compartment wall/floor or built into a wall then it needs to be resistance at least half of wall/door
     • Fire-Stopping
       • In addition to any other precautions in this document the following must also be fire-stopped.
         • Joints between fire-separating elements (fire barries)
         • openings that pass through fire-separating element
           • Few as possible
           • Small as practical
           • Fire stopped
       • Materials used for fire stopped should be supported by ones of limited combustability
         • In all cases where unsupported span is less than 100mm
         • Where non-rigid materials have been used.
       • Brands of fire stopping & sealing systems my be used on the premis that they have been tested.
         • There are other products whos original use was not for fire stopping but are good at it can be used.
           • Cement mortar
           • Gypsum-based plaster
           • cement-based or gypsum-based cermiculite/perlite plaster
           • Intrumescent mastics

2. B4 External Fire Spread

   • (1) The external walls of the building shall adequatly resist the spread of fire over the walls and from one building to another, having regard to the height, use and position of the building (2) The roof of the building shall adequatley resit the spread of fire over the roof and from one building to another, having regard to the use and position of the building.
   • Construction of external walls and sepiration between them