Sub-sill on Hob Building Codes & Rules

- Sub Sill on Hob Tools™ simplifies the National Construction Code (NCC) with interactive graphics, including deemed to comply & best practices.

Floor system

≥ 1 : 80 falls to Drainage
Concrete required over habitable spaces

Roof Terrace or Podium DESIGN

NCC 2022 V1

Balcony DESIGN

NCC 2022 V1

≥ 1 : 80 falls to Drainage
Concrete required over habitable spaces

End Cap

Fully seal to sub-sill
≥ 6mm gap to reveal with backing rod & sealant

End Cap WATERPROOFING

NCC 2022 V1

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Fully seal to sub-sill
≥ 6mm gap to reveal with backing rod & sealant

Flooring

Skirting

End cap

Membrane Height

(External)

if Tiled

Floor System

Fillet

Manufacturer's System Requirement

Metal Angle

Fixings at 300mm^{Manufacturer's System Requirement} CTS
Plugged, or
Nylon Anchors

Substrate

AS 3958.1:2007, 5.4.3 (g)

Tile ≥ 3mm^{AS 3958.1:2007, 5.4.3 (g)} below

Top of Hob

≥ 1 : 80

AS 4654.2:2012, 2.5.2

≥ 1 : 100^{AS 4654.2:2012, 2.5.2}

AS 3958.1:2007, 5.4.6

1.5^{AS 3958.1:2007, 5.4.6}

Fall

≥ 1 : 80

Fall

AS 4654.2:2012, 2.5.2

≥ 1 : 100^{AS 4654.2:2012, 2.5.2}

AS 3700:2018, 4.7.2

Weepholes^{AS 3700:2018, 4.7.2}

Direct water out of sub-sill to building exterior

AS 4654.2:2012, 2.8.3

≥ 10^{AS 4654.2:2012, 2.8.3}

Class III

Membrane

Packing

Fillet

Floor System

Finished Level

Screed

Threshold

Sub-Sill

Underlay / Acoustic Mat

Expansion Joint

Substrate

Floor Finish

Fixings

≤ 600mm CTS^[1]
Seal to prevent water ingress^[2]

Fixing RULES

NCC 2022 V3

All Building Classes

NCC 2022 J5D5, H6D2, & HP13.4.4 [2019 J3.4, 3.12.0, 3.12.3.3]

May 2023

NCC 2022 HP, 13.4.4

NCC 2022 Vol 1, J5D5 (1)

NCC 2022 Vol 2, H6D2 (1)

AS 4654.2:2012, 2.8.3

Building envelope sealing in compliance to the NCC^{NCC 2022 HP, 13.4.4NCC 2022 Vol 1, J5D5 (1)NCC 2022 Vol 2, H6D2 (1)}
Seal^{AS 4654.2:2012, 2.8.3}
Between sill, packer, & Membrane
Over fixing head

Fixing BEST PRACTICE

NCC 2022 V1

AS 4654.2:2012, 2.8.3

Manufacturer's Requirement

≤ 600mm CTS^{AS 4654.2:2012, 2.8.3}
Seal to prevent water ingress^{Manufacturer's Requirement}

Substrate

Smooth, clean, dry & dust free surface^[1]

Substrate RULES

NCC 2022 V3

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.5.1

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.6

Building elements in Wet Areas to be Waterproof or Water Resistant to NCC^{AS 4654.2:2012, 2.5.1AS 4654.2:2012, 2.5.1NCC 2022 Vol 1, F1D5}
Compatible with the Waterproofing Membrane System^{NCC 2022 Vol 2, H2D8}
Prohibited^{NCC 2022 HP, 10.2.6}
Particleboard Sheeting
Tile & Slate Underlay

Liquid applied membrane PREPARATION

NCC 2022 V2

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.5.3.1

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

AS 4654.2:2012, 2.5.3.1

Building elements in Wet Areas to be Waterproof or Water Resistant to NCC Specification^{AS 4654.2:2012, 2.5.3.1NCC 2022 Vol 1, F1D5NCC 2022 Vol 2, H2D8}
Smooth, clean, dry & dust free surface^{NCC 2022 HP, 10.2.1}
Fill voids
Grind smooth any protrusions
Free of formwork distortions
< 8.0% moisture level prior to application^{AS 4654.2:2012, 2.5.3.1}
Confirm Manufacturer's Recommendations

Substrate PREPARATION

NCC 2022 V1

Partially bonded membrane PREPARATION

NCC 2022 V2

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.5.3.2

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

Building elements in Wet Areas to be Waterproof or Water Resistant to NCC^{AS 4654.2:2012, 2.5.3.2AS 4654.2:2012, 2.5.3.2NCC 2022 Vol 1, F1D5}
Smooth, clean, dry & dust free surface^{NCC 2022 Vol 2, H2D8}
Fill voids
Grind smooth any protrusions
Free of formwork distortions
< 8.0% moisture level, or^{NCC 2022 HP, 10.2.1}
Vent to relieve vapour pressure

Unbonded membrane PREPARATION

NCC 2022 V3

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.5.3.3

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

Building elements in Wet Areas to be Waterproof or Water Resistant to NCC^{AS 4654.2:2012, 2.5.3.3NCC 2022 Vol 1, F1D5NCC 2022 Vol 2, H2D8}
Smooth, clean, dry & dust free surface^{NCC 2022 HP, 10.2.1}
Fill voids
Grind smooth any protrusions
Free of formwork distortions

AS 4654.2:2012, 2.5.3

Smooth, clean, dry & dust free surface^{AS 4654.2:2012, 2.5.3}

Zero Threshold

Termite Control

Termite control required for Ground Level floor junctions^[1]
≥ 75mm^[2] slab exposure above the external finished floor level to allow easy detection of termites

Termite MANAGEMENT

NCC 2022 V4

Class 1 & 10

NCC 2022 H1D3 & HP3.4.2 [2019 3.1.4.3]

May 2023

NCC 2022 HP, 3.4.2

AS 3660.1:2014, 4.4

NCC 2022 Vol 2, H1D3

Termite Management compliant to the NCC^{NCC 2022 HP, 3.4.2}
Inspection Zone^{AS 3660.1:2014, 4.4NCC 2022 Vol 2, H1D3}
≥ 75mm exposed Concrete Face
Off form, smooth surface, free of Ripples or Honeycombing
Tiling, Render, Vapour Barrier, Flashings, Structures & the like, not allowed to bridge this Zone

Termite RISK

NCC 2022 V3

Class 1 & 10

NCC 2022, H1D3 & HP3.4.1 [2019 3.1.4.2]

May 2023

NCC 2022 HP, 3.4.1(2)

NCC 2022 HP, 3.4.1 (1) (b)

NCC 2022 HP, 3.4.1

Termite Management System Required if^{NCC 2022 HP, 3.4.1(2)}
Location is identified at Risk of Attack, &
Any Primary Building Element is susceptible
Primary Building Elements are^{NCC 2022 HP, 3.4.1 (1) (b)}
Any member designed to take Loads
Wall, Roof, Ceiling, Floor, Ramp or Stair Framing
Any bracing or other framing members
Materials not susceptible to attack^{NCC 2022 HP, 3.4.1}
Metals
Concrete
Masonry
Fibre-reinforced Concrete
Naturally resistant Timber
Preservative-treated Timber

NCC 2022 HP, 3.4.1

AS 3660.1:2014, 4.4

Termite control required for Ground Level floor junctions^{NCC 2022 HP, 3.4.1}
≥ 75mm^{AS 3660.1:2014, 4.4} slab exposure above the external finished floor level to allow easy detection of termites

Floor Finish

≥ 1 : 100^[1] fall to Drainage
≥ P3 or R10 Slip Rating^[2]

Surface FINISHES

NCC 2022 V4

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.15.2

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

AS 4654.2:2012, 2.15.1

AS 4654.2:2012, 2.15.3

Building elements in Wet Areas to be Waterproof or Water Resistant to the NCC^{AS 4654.2:2012, 2.15.2AS 4654.2:2012, 2.15.2NCC 2022 Vol 1, F1D5}
Overlaying system not to harm & be suitable with the membrane^{NCC 2022 Vol 2, H2D8}
Membrane bonded to topping or bedding^{NCC 2022 HP, 10.2.1}
≥ 10mm movement joint width at ≤ 4.5m CTS
Structural topping^{AS 4654.2:2012, 2.15.1}
≥ 50mm thick with light mesh reinforcement
Install double slip sheet on top of membrane
Align movement joints in finishes over all building construction, control or movement joints^{AS 4654.2:2012, 2.15.3}

AS 4654.2:2012, 2.5.2

HB 198:2014, 5.1

≥ 1 : 100^{AS 4654.2:2012, 2.5.2} fall to Drainage
≥ P3 or R10 Slip Rating^{HB 198:2014, 5.1}

Sub-sill with Set Down

Membrane

≥ 1 : 100^[1] fall to Drainage
System compatible & to suit application^[2]

Membrane AUDIT

NCC 2022 V1

All building classes

AS 4654.2 2012, 2.16

14 Sep 2012 to Current

Membrane RULES

NCC 2022 V5

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.5.2

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

AS 4654.2:2012, 2.3

AS 4654.2:2012, 2.5.3

AS 4654.2:2012, 2.7

AS 4654.2:2012, 2.6.2

Building elements in Wet Areas to be Waterproof or Water Resistant to the NCC^{AS 4654.2:2012, 2.5.2NCC 2022 Vol 1, F1D5NCC 2022 Vol 2, H2D8}
Falls^{NCC 2022 HP, 10.2.1}
≥ 1 : 100 fall in Membrane to Drainage Outlet
Structural Substrate or Screed to form the required Falls
Design & installation in accordance with AS 4654.1^{AS 4654.2:2012, 2.3}
Membrane movement Class I, II, or III
To suit intended service conditions
Substrate to be smooth, clean, dry & dust-free^{AS 4654.2:2012, 2.5.3}
Fillets & Bond Breakers installed on all corners^{AS 4654.2:2012, 2.7}
Lay & allow to cure as per Manufacturer's Recommendations^{AS 4654.2:2012, 2.6.2}

Waterproof Membrane BEST PRACTICE

NCC 2022 V1

AS 4654.2:2012, 2.5.2

AS 4654.2:2012, 2.5.1

≥ 1 : 100^{AS 4654.2:2012, 2.5.2} fall to Drainage
System compatible & to suit application^{AS 4654.2:2012, 2.5.1}

Membrane Height

Height varies with wind class^[1]

Height RULES

NCC 2022 V7

All Building Classes

NCC 2022 F1D5, H2D8, & HP10.2 [2019 F1.4, 3.8.1.2, 3.8.1.3]

May 2023

AS 4654.2:2012, 2.8.1

NCC 2022 Vol 1, F1D5

NCC 2022 Vol 2, H2D8

NCC 2022 HP, 10.2.1

Building elements in Wet Areas to be Waterproof or Water Resistant to the NCC^{AS 4654.2:2012, 2.8.1NCC 2022 Vol 1, F1D5NCC 2022 Vol 2, H2D8}
Measured from top of finished external level to height of Membrane^{NCC 2022 HP, 10.2.1}
FFL in the case of a finish on a Screed Bed, or
Base of Linear Drain at Zero Threshold Entry, or
Substrate Membrane where Pavers on Pedestals
Height sufficient to prevent wind-driven water entry

AS 4654.2:2012, 2.8.1.1

Height varies with wind class^{AS 4654.2:2012, 2.8.1.1}

External Waterproofing Overview