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Placement of Ducts and HVAC Systems in Conditioned Space:

An Overview

EEBA Excellence in Building Conference

October 24, 2001

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 1 of 25

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•Energy savings from reducing forced air exchange due to duct leakage

Why move ducts inside?

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 2 of 25

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•Reduce pressure imbalance problems

•Energy savings from less hostile duct environment

•Reduced heating & cooling loads—equipment downsizing

Why move ducts inside? (continued)

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 3 of 25

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•Basement + interior walls

•Conditioned crawl space + interior walls

•Dropped HVAC coffer

•Raised HVAC coffer

•Floor truss space (two-story plans)

•Unvented roof system

•Warning: Combustion Appliance Location

Duct Location Options

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 4 of 25

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Basement Duct System

•Standard system in many regions

•Second floor ducts must be in first floor interior walls or trunks off of floor system—not in attic.

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 5 of 25

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Conditioned Crawl Space

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 6 of 25

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Conditioned Crawl Space Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 7 of 25

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Conditioned Crawl Space Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 8 of 25

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Dropped Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 9 of 25

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Dropped Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 10 of 25

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Dropped Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 11 of 25

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Raised Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 12 of 25

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Raised Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 13 of 25

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Raised Ceiling Coffer Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 14 of 25

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Engineered Floor Truss Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 15 of 25

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Engineered Floor Truss Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 16 of 25

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Engineered Floor Truss Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 17 of 25

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Engineered Floor Truss Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 18 of 25

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Engineered Floor Truss Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 19 of 25

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Unvented Roof Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 20 of 25

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Unvented Roof Duct System

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 21 of 25

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Unvented Roof Ducts: Energy Comparisons

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 22 of 25

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Unvented Roof: Air Sealing Locations

Garage kneewalls

Porch kneewalls

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 23 of 25

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Unvented Roof: Construction Detail

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 24 of 25

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Unvented Roof: Construction Detail

PR-0111: Placement of Ducts and HVAC Systems in Conditioned Space—An Overview Page 25 of 25

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