Part 5.5 Isolated piers

(1) Part 5.5 is subject to the limitations set out in H1D5(5)(c).

(2) Part 5.5 need not be complied with if H1D5(5)(a) or (b) are complied with.

Isolated piers supporting carports, verandahs, porches and similar roof structures, or vehicle access door openings, which form part of the main roof, or are attached to a wall of a Class 1 building must—

1. be not less than 290 x 290 mm in section; and
2. be not more than 2.7 m high (see Figure 5.5.2); and
3. be spaced at not more than 3 m centres (see Figure 5.5.2); and
4. provide a bearing length of not less than 150 mm for any supported members; and
5. comply with the relevant provisions of this Part.

Isolated piers supporting tiled roofs must have—

1. a built-in 30 x 0.8 mm galvanised steel strap fixed to the roof structure that extends the full height of the pier; and
2. a 4.6 grade M12 galvanised steel rod which is cast into the footing when poured and looped and fixed around the galvanised steel strap required by (a).

Isolated piers supporting sheet roofs must have—

1. a built-in 30 x 0.8 mm galvanised steel strap fixed to the roof structure extending the full height of the pier which is looped and fixed around a 4.6 grade 16 mm diameter galvanised steel rod cast into the footing when poured; or
2. a 4.6 grade M16 galvanised steel rod cast into the footing, threaded at the top and extending the full height of the pier to connect to the roof structure.

Piers for freestanding carports must—

1. be not less than 290 x 290 mm in section with the central core filled with 20 MPa concrete, or an exposure class mortar (see Table 5.6.3) complying with 5.6.3; and
2. have the core reinforced with one Y16 steel reinforcing rod cast into the footing and extending the full height of the pier to connect to the roof structure.

Subfloor isolated piers must be not less than 190 x 190 mm in section and comply with Figure 5.5.6 for height requirements.