Footings are critical to the structural stability of a cottage. Footings are designed based on site topography, soil type, stability, and any other local requirements during the design process. Footings must be designed with reference to Residental Slab and Footing Code AS2870.

Types of footings include:

A. Strip Footings
They are suitable for stable sites (Class A or S sites) that are flat or sloping. Timber framed construction with brick up to floor level may be constructed onto strip footings in reactive clay areas (Class M and H sites).


B.Pier and beam footings
Footing beams for brick and brick veneer cottages on reactive clay soils (Class M and H) generally require piering to stable ground. Piering is always required where footings are influenced by adjacent drainage or Water Board sewer mains. Sites containing extremely reactive ground or uncontrolled filling require piering for footings of all types of construction.


C. Foundation Slabs (Raft Slabs)
Types include: the conventional concrete slab with perimeter and internal beams and the (waffle pod) slab which has internal ribs 110mm wide spaced at 1200mm centres in both directions. This type of footing is used for all types of construction on all site classifications, however, there usage is generally restricted to sites containing less than 2.0m of fall. For steeply sloping sites other types of footing construction should be considered.


D. Elevated Construction
Homes on steep sites or sites prone to flooding generally have elevated floors supported on timber poles, steel posts, brick piers or concrete columns. Bracing is required to control sidesway. Timber poles can be of treated pine or hardwood. Treated pine poles can be set into concrete filled holes drilled into the ground while hardwood poles should be supported by a concrete plug in the base of the drilled pier hole which is filled with gravel.


A Termimesh™ sock is provided at the base of all hardwood poles for termite protection. Steel posts are generally fixed to concrete footing pads or piers with bolts.

In any case, whenever a designer of a building needs advice on the structural system for his building please contact Kneebone & Beretta Group on This email address is being protected from spambots. You need JavaScript enabled to view it. and an engineer will get back for your assistance.