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Read through the material below, then test your understanding.
Module Lessons
Rainwater
Rainwater Systems, Materials, and Profiles
Roof Area Calculations and Sizing
Brackets, Falls, and Setting Out
Jointing, Expansion, and Downpipes
Terminations, Harvesting, and Maintenance
Introduction to Sheet Lead Weatherproofing
Lead Tools, Safety, and Handling
Types of Flashing and Fixing Methods
Testing and Commissioning Rainwater Systems
Lesson Overview
Sizing rainwater systems requires calculating the effective roof area and anticipated rainfall flow rate. Correct calculations ensure gutters and outlets prevent water penetration, foundation erosion, and structural damp.
Learning Objectives
Calculate effective roof area using both the standard formula and roof pitch factors.
Determine design flow rates based on UK rainfall intensity and storm deluge data.
Identify how outlet positioning, geometry, and gutter angles affect drainage capacity.
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