Fire-Rated Penetrations for Plumbers – Collars, Wraps & Mastic Basics

SNZ Plumbing Estimating · 2026-05-18

Fire-Rated Penetrations for Plumbers – Collars, Wraps & Mastic Basics

NCC Volume One Specification 13 explained: plastic vs metal pipes, one collar vs two, fire collars plumbing penetrations, Trafalgar FyreCOLLAR Sydney picks 2025/2026

When plumbing pipes pass through fire-rated walls, floors or slabs in multi-storey apartments, commercial buildings, or Class 2–9 projects, you must maintain the Fire Resistance Level (FRL) of the element. Missing fire-rated penetrations is one of the most common defects at practical completion and handover in Sydney — leading to rectification orders, delays and extra costs.

The rules are in NCC Volume One Specification 13 (Penetration of walls, floors and ceilings by services), tested to AS 1530.4 and AS 4072.1. Here’s the simple, practical guide for plumbers.

Plastic Pipes vs Metal Pipes – Protection Methods

One Collar vs Two – Slab vs Wall

Slabs / Floors (horizontal penetrations): One collar — installed on the underside (fire exposure side in most tests).

• Cast-in collars (during pour) or retrofit (after core drill).
• Reece examples: Promat PROMASEAL CIL Low Cast-In 50mm (code ~1007749) or Trafalgar cast-in series.

Walls (vertical penetrations):

• Standard retrofit collars (hinged): Two collars — one on each side of the wall (protects from fire either direction).
• Dedicated wall collars (e.g., Promat PROMASEAL FCW): One collar — inserted mid-wall cavity.
• Always check the manufacturer’s test report for the specific system (FRL rating and number of collars).

Mastic / Intumescent Sealant – The Essential Finish

• Fill annular gaps (space around pipe) with intumescent mastic (gun-applied) on both sides of wall or underside of slab.
• Never skip — even a perfect collar fails if gaps are unsealed.
• Reece picks: FyrePEX High Performance Mastic (code 3210024) or FyreFLEX Acrylic Sealant (code 3210022) – ~$20–$30 per cartridge.

Quick Compliance Checklist for Sydney Jobs

• Plastic pipe through slab → 1 collar underside
• Plastic pipe through wall → 1–2 collars (check product test report)
• Metal pipe through slab/wall → TWRAP wrap + mastic
• Allow $150–$600 per penetration (material + labour)
• Specify “tested to AS 1530.4 / AS 4072.1” and keep reports for certifier
• Common defect: No mastic in gaps — always seal both sides

At SNZ Plumbing Estimating, we include compliant fire-rated penetrations in every multi-storey or commercial quote — no surprises at inspection or handover.