Dryer Vents

Section M1502 IRC

Section G2439 IRC (Applicable to Gas Dryers)

FBC Residential

Code Reference

Area or Item

 

M1502.1

Ducts should be installed per manufacturer

M1502.2

Duct system independent

M1502.4.2

Duct Installation

M1502.3

Exterior Duct Termination

G2439.3

Exhaust installation requirements

M1502.4.1

G2439.7.1

Duct material and size requirements

M1502.4.5

G2439.7.4

Dryer Vent Length

Length is based on code or manufacturer’s instructions. Sections 2439.7.4.1-3 note options

M1502.4.7

G2439.7.6

Exhaust duct mandatory

M1502.4.3

G2439.7.3

Dryer connectors or transition ducts

G2439.6

Protection requirements

G2439.2

Fire rated duct penetrations

M1502.4.4 G2439.4

Power Ventilators

M1502.4.5.3 G2439.7.4.3

Power Ventilator Length Requirements

 

G2439.5

Make up air (gas dryers)

FL Exception!   PVC can be used under slab construction as an approved material.

Reduction table for elbows and fittings

DUCT FITTING TYPE

REDUCTION LENGTH

4 inch radius mitered 45-degree elbow

2 feet, 6 inches

4 inch radius mitered 90-degree elbow

5 feet

6 inch radius smooth 45-degree elbow

1 foot

6 inch radius smooth 90-degree elbow

1 foot, 9 inches

8 inch radius smooth 45-degree elbow

1 foot

8 inch radius smooth 90-degree elbow

1 foot, 7 inches

10 inch radius smooth 45-degree elbow

9 inches

10 inch radius smooth 90-degree elbow

1 foot, 6 inches