Roofs

Module from the Storage Tank Engineering Curriculum curriculum.

Module 3 - Roof Types · Learning Objectives · 1. Select fixed cone roof for large flat, self-supported roofs · 2. Select geodesic dome (aluminum) for IFR cover above floating roof · 3. Design external floating roof (EFR) per API 650 Annex C · 4. Design internal floating roof (IFR) per API 650 Annex H · 5. Apply emergency venting per API 2000 (atmospheric tanks) · Roof Type Selection

Roof Type	Max Diameter	Emissions	Cost	Maintenance	Use
Cone roof (self-supporting)	60 ft	Vapor space losses	Lowest	Low	Heavy HC, low VP
Cone roof (supported)	Unlimited	Vapor space losses	Low	Low	Utilities, water
Dome (welded steel)	100 ft	Vapor space losses	Medium	Low	Chemical
Geodesic dome (aluminum)	Unlimited	Cover IFR	Medium	Low	Gasoline + aluminum IFR
External floating roof (EFR)	400 ft	<1% vs fixed	High	Seal maintenance	Gasoline, crude
Internal floating roof (IFR)	Unlimited	<5% vs fixed	High	Seal + roof maint	Gasoline in windy area
Double-deck floating	400 ft	Best emissions	Highest	Seal	High RVP hydrocarbons

Source: Storage_Tank_Engineering_Curriculum_v1.xlsx · Sheet: Roofs

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