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Donnie D. Mortimer
09-26-2016, 08:57 AM
Is there a clearance requirement for a dryer vent termination to ground or flat surface? I have seen low mounted locations and noted one 4 inches from a flat surface. I have been unable to find anything on clearance regarding distance from the vent. I see where it could easily be blocked. Thoughts on this?
Thanks

Jack Feldmann
09-26-2016, 02:00 PM
There is a distance requirement from openings to the building, but I don't think there is a code for distance to anything else. Obviously, they should be well away from a/c units, but I don't think that's in the code either. I'm not near my code book, but I'm sure someone else can cite the code.

Jerry Peck
09-26-2016, 02:23 PM
(bold and underlining are mine)
M1501.1 Outdoor discharge.
The air removed by every mechanical exhaust system shall be discharged to the outdoors in accordance with section M1506.3. Air shall not be exhausted into an attic, soffit, ridge vent or crawl space.
Exception: Whole-house ventilation-type attic fans that discharge into the attic space of dwelling units having private attics shall be permitted.

(My note: M1501.1 states "The air removed by every mechanical exhaust system", as in "EVERY" mechanical exhaust system, which means that "EVERY" mechanical exhaust system shall meet the requirements of M1501.1 AND 1506.3 (because 1501.1 says so) AND any other specific requirements, such as M1502.3 for M1502 Clothes Dryer Exhaust ... (because the code says 'the most restrictive shall apply'.)

M1502 Clothes Dryer Exhaust
M1502.3 Duct termination.
Exhaust ducts shall terminate on the outside of the building. Exhaust duct terminations shall be in accordance with the dryer manufacturer's installation instructions. If the manufacturer's installation instructions do not specify a termination location, the exhaust duct shall terminate not less than 3 feet (914 mm) in any direction from openings into the buildings. Exhaust duct termination shall be equipped with a backdraft damper. Screens shall not be installed at the duct termination.


M1506.3 Exhaust openings.
Air exhaust opening shall terminate not less than 3 feet (914 mm) from property lines; 3 feet (914 mm) from operable and nonoperable openings into the building and 10 feet (3048 mm) from mechanical air intakes except where the opening is located 3 feet (914 mm) above the air intake. Openings shall comply with Sections R303.5.2 and R303.6.


Note that "operable and nonoperable opening into the building" include soffit vents, gable vents, ridge vents, off-ridge vents - any opening into the building, which includes the attic and crawlspace..

Donnie D. Mortimer
09-26-2016, 06:11 PM
Thanks Jack and Jerry for your input.

ROBERT YOUNG
09-27-2016, 06:50 AM
M1502.3 Duct termination.

Exhaust ducts shall terminate on the outside of the building. Exhaust duct terminations shall
be in accordance with the dryer manufacturer’s installation instructions.
If the manufacturer’s instructions do not specify a termination location, the exhaust duct shall terminate not less than 3
feet (914 mm) in any direction from openings into buildings.
Exhaust duct terminations shall be equipped with a back-draft damper.
Screens shall not be installed at the duct termination.

M1502.4 Dryer exhaust ducts. Dryer exhaust ducts shall conform to the requirements of Sections M1502.4.1 throughM1502.4.6.


M1502.4.1 Material and size. Exhaust ducts shall have a smooth interior finish and shall be constructed of metal a

minimum 0.016-inch (0.4 mm) thick. The exhaust duct size shall be 4 inches (102 mm) nominal in diameter.


M1502.4.2 Duct installation. Exhaust ducts shall be supported at 4 foot (1219 mm) intervals and secured in place. The

insert end of the duct shall extend into the adjoining duct or fitting in the direction of airflow. Ducts shall not be joined
with screws or similar fasteners that protrude into the inside of the duct.


M1502.4.3 Transition duct. Transition ducts used to connect the dryer to the exhaust duct system shall be a single length

that is listed and labeled in accordance with UL 2158A. Transition ducts shall be a maximum of 8 feet (2438 mm) in
length. Transition ducts shall not be concealed within construction.


M1502.4.4 Duct length. The maximum allowable exhaust duct length shall be determined by one of the methods

specified in Section M1502.4.4.1 or M1502.4.4.2.


M1502.4.4.1 Specified length. The maximum length of the exhaust duct shall be 25 feet (7620 mm) from the connection

to the transition duct from the dryer to the outlet terminal. Where fittings are used, the maximum length of the exhaust
duct shall be reduced in accordance with Table M1502.4.4.1.


M1502.4.4.2 Manufacturer’s instructions. The size and maximum length of the exhaust duct shall be determined by the

dryer manufacturer’s installation instructions. The code official shall be provided with a copy of the installation
instructions for the make and model of the dryer at the concealment inspection. In the absence of fitting equivalent length
calculations from the clothes dryer manufacturer, Table M1502.4.4.1 shall be used.


M1502.4.5 Length identification. Where the exhaust duct is concealed within the building construction, the equivalent

length of the exhaust duct shall be identified on a permanent label or tag. The label or tag shall be located within 6 feet
(1829 mm) of the exhaust duct connection.
M1502.4.6 Exhaust duct required. Where space for a clothes dryer is provided, an exhaust duct system shall be
installed. Where the clothes dryer is not installed at the time of occupancy the exhaust duct shall be capped or plugged in
the space in which it originates and identified and marked “future use.”

Exception: Where a listed condensing clothes dryer is installed prior to occupancy of the structure.

Hal Metzner
09-27-2016, 01:09 PM
Brian,
you should have just received CREIA'S INSPECTOR JOURNAL in the mail and there is a section all about dryer's installing and venting etc, you should be able to get most of your questions answered there.

ROBERT YOUNG
09-27-2016, 01:23 PM
You can try this as well.
I can not find dryer vent termination grade/ground clearance.

Clothes Dryer Exhaust Vent Clearance Distances (http://inspectapedia.com/Appliances/Clothes_Dryer_Vent_Clearances.php)

All the best.

Jerry Peck
09-27-2016, 06:04 PM
You can try this as well.
I can not find dryer vent termination grade/ground clearance.

Clothes Dryer Exhaust Vent Clearance Distances (http://inspectapedia.com/Appliances/Clothes_Dryer_Vent_Clearances.php)

All the best.

That link ponders a code they could not find which addresses clothes dryer vents and gas meters ... clothes dryer vents are "building openings" ... :)

ROBERT YOUNG
09-27-2016, 07:41 PM
That link ponders a code they could not find which addresses clothes dryer vents and gas meters ... clothes dryer vents are "building openings" ... :)

Thought Danial Friedman's inspectapedia (https://www.google.ca/search?rlz=1C1CHBF_enCA711CA711&espv=2&q=Daniel+Friedman+inspectapedia&spell=1&sa=X&ved=0ahUKEwjcsfqa2rHPAhVCbSYKHfIbDqcQvwUIGygA) website might cover more areas unexplored by the OP.