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Lesson 19 of 22

Class 1 & Class 2 Flue Construction

Read through the material below, then test your understanding.

Module Lessons

Domestic Fuel Systems, Combustion & Flues

Lesson Overview

This lesson covers the construction, materials, and regulatory standards for Class 1 masonry chimneys and Class 2 pre-cast concrete flue block systems used in domestic installations.

Learning Objectives

Identify the dimensions, linings, and masonry specifications required for Class 1 chimneys.

Explain the design, jointing, and dimensional requirements for Class 2 pre-cast flue block systems.

Recognise essential construction practices to prevent flue degradation, fire spread, and plaster cracking.

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