RESIDENTIAL DECKS
BUILDING DEPARTMENT
100 Northeast 7th Avenue
P.O. Box 244
Little Falls, MN 56345-0244
(320) 616-5500
PERMITS
A building permit is required for construction of a deck that will be more than 30 inches above grade
and/or attached to a dwelling.
SUBMITTALS REQUIRED FOR PERMIT
Two (2) copies of construction plans showing proposed designs and materials.
Drawings are to be drawn to scale on paper and may include:
□
Site Plan showing lot dimensions and locations of existing and proposed structure(s)
□
Floor Plan providing:
 Outside lines and dimensions of the deck, location of stairs and lighting
 Lumber type
 Size and spacing of footings, posts, joists, beams, headers, decking, guardrails and
handrails

Cross Sections and/or Elevations of rear or side views showing:
 Diameter and depth of footings
 Height of deck from grade
 Guardrail height and spacing of intermediate rails
 Connection to home or principal building
□
REQUIRED INSPECTIONS
When a building permit is required for a deck, the following inspections must be requested:
 Site/Footing Inspection – to approve deck location and footings (prior to placement of concrete)
 Framing – after completion of structural frame.
 Final – Upon completion of the deck.
Please call (320) 616-5500 to arrange an inspection 24 hours in advance.
Revision 1
STRUCTURAL RECOMMENDATIONS:
FOOTINGS: All footings must extend at least 60 inches below grade. Frost footings are required for decks
attached to dwellings or structures that have frost footings. Footings for decks generally are 12 to 16
inches in diameter at their base. Footings for three season and screen porches are generally 18 to 24
inches in diameter at their base. If you intend to add a porch roof at a later date, you may want to design
for those loads now. The building inspector will verify the footing sizes based on deck load calculations.
LUMBER & CONSTRUCTION: Lumber exposed to weather must be redwood, cedar, or treated (.40 or .60
ACQ or copper azole. Sodium borate is not approved for outdoor use). Decks must be designed to
support a total load of 50 pounds per square foot (see attached chart for lumber sizing).
Decking must be at least 1 ¼ inches in thickness for floor joists spaced 24 inches on center, and 1 inch
in thickness for floor joists spaced 16 inches on center.
Joists must not overhang beams (cantilever) by more than 12 inches for 2x6, 18 inches for 2x8, and 24
inches for 2x10’s and larger. Beams must not overhang posts by more than 12 inches unless special
design is approved. Longer overhangs/cantilevers may require an engineered design.
Ledger boards or rim joists must be attached directly to solid wood framing members of the house.
Siding should be removed. Connections between deck and dwelling shall be weatherproof/flashed and
caulked.
All hardware and fasteners must be corrosion resistant. New lumber treatments ACQ and copper
azole have been found to be more corrosive to wood than the old treatment CCA (see attached
memorandum). All fasteners and hardware in contact with treated lumber must be Triple Coated
Zinc (G180 or greater), Hot Dipped Galvanized or Stainless Steel. Standard galvanized hardware
(G60) will not be accepted.
GUARDRAILS: Guardrails must be installed around the deck and stair if the deck or stair is over 30 inches
above grade. Guardrails must be at least 36 inches in height and must not permit the passage of a 4 inch
sphere through the intermediate rails or pickets.
STAIRWAYS: Stairways must be at least 36 inches in width. Maximum rise tread to tread is 7 ¾” inches.
Minimum tread depth is 10 inches. The largest riser height shall not exceed the smallest by more than
3/8 inch within any flight of stairs. Open risers are permitted, provided that the opening between treads
do not exceed 4 inches for risers greater than 30 inches above grade. The triangular opening formed by
tread, riser and guardrail shall be small enough to prevent a 6” sphere from passing through. Exterior
stairways shall be provided with an artificial light source located in the immediate vicinity of the top
landing of the stairway.
HANDRAILS: Graspable handrails must be provided on at least one side of stairways having 4 or more risers.
Handrail height must be between 34 and 38 inches in height above the nosing of the treads and extend
continuously for the full length of the stairway. Handrails projection from a wall must have a space of
not less than 1 ½ inch between the wall and the handrail. The handgrip portion of handrails must be not
less than 1 ¼ inch and no more than 2 inches in cross sectional dimension and must have a smooth
surface with no sharp corners. Ends of handrails must have returns.
LANDINGS: There shall be a floor or landing at the top and bottom of each stairway. Exterior stairs must be
provided with a top landing where the deck does not serve as the landing. The width of each landing
shall not be less than the width of the stairway served and length of landing shall be 36” in length.
This informational document may not comprehensively address all City ordinances regarding the subject
addressed. It is provided to serve only as a helpful guide during design phase and permit application. Any work
requiring permits is not allowed until all required permits have been issued by the City of Little Falls.