Description

B1 Structure Acceptable Solution B1/AS3 Second Edition provides structural design guidance for small chimneys and hearth slabs associated with solid fuel-burning domestic appliances.

The Acceptable Solution B1/AS3 Second Edition outlines acceptable construction methods for chimneys made of brick, concrete, or precast pumice concrete including specifications for materials, reinforcement, foundations, and seismic restraints.

The document also details requirements for hearth slabs, including dimensions, reinforcement, and installation on timber or concrete floors.

It includes bracing provisions for earthquake resistance.

This edition has been published in a standalone format.

Scope

This acceptable solution applies to small chimneys and to supporting hearth slabs for solid fuel burning domestic appliances. 

Items outside the scope of this document:

• This acceptable solution does not include the necessary provisions to prevent the outbreak of fire. It is to be read in conjunction with Acceptable Solution C/AS1, Acceptable Solution C/AS2, or Verification Method C/VM1.
• Depending on the particular installation, different hearth dimensions may be necessary to meet the requirements in Building Code clause C2 Prevention of fire occurring.