DECKS This handout is written only as a guide. It is not intended nor shall it be considered a complete set of requirements. CALL BEFORE YOU DIG, CALL 811 Gopher One or 651-454-0002 to locate all utilities in the deck area. Please allow 48 hours before digging to allow all entities to locate their underground utilities. www.gopherstateonecall.org. A building permit is required for all decks attached to the home, 30 above grade or needing footings. Please call the building department to verify if a permit is needed. Your application must include: A site plan of the lot showing distances from property lines. Please check with us to see if a survey is on file, otherwise we can print an aerial photo with dimensions. An 8 ½ x 11 copy of your plan showing locations of all the structural elements. o Section of the deck showing the post and footing. o Size of the deck. o Plan view. o Joist sizes and spacing. o Beam sizes. o Post sizes and spacing. o Footing sizes and depth. o Guardrail details. o Refer to illustrations in this handout. Please be aware that a future screen porch, addition or sun porch requires other footing sizes and framing information. APPROVED PLASTIC/COMPOSITE DECKING MATERIALS Information on approved materials to be used in Minnesota can be found at www.10klakes.org. Other products may be submitted for approval by the City Building Official, within limitations of the Evaluation Service Report. www.icc-es.org/evaluation_reports/index.shtml International Code Council Evaluation report index. www.nateval.org National Evaluation Service, Inc. REQUIRED INSPECTIONS Footings: After the holes are dug and BEFORE the concrete is placed. Framing: Only required if the posts, beams and joists are close to the grade and not visible when completed. Final: When the deck is completed.
DECKS - GENERAL BUILDING CODE REQUIREMENTS Exposed Wood: Exposed wood (posts, beams, joists, guardrails and decking) is required to be of approved wood with natural resistance to decay (treated, cedar, etc.). Composite decking must be approved material for Minnesota use. Posts of treated wood to be rated for ground contact. Easements: Check for easement locations on your property, as structures aren t allowed in easements. Flashing: All connections between the deck and the dwelling shall be weatherproofed flashing. Foam Core Rim Board: Minimum 5 ½ lag bolt with a minimum 2 x 4 blocking behind the rim boards is required to attach the deck when using a manufactured insulation foam core rim board. Frost Footings: Frost footings are required when the deck is to be attached to a dwelling or garage that has frost footings (see illustration). Guardrails: A 36 minimum high guardrail must protect decks 30 and more above grade. Spindles have a maximum 4 opening at the widest area. Stair risers can only have a maximum 4 opening. Handrails: Measure from the front of the step (tread) vertically 34 to 38 high. One per flight of stairs. Headers: Must be supported by approved framing anchors such as joist hangers. An example of headers is where the deck is located at a cantilever on the dwelling. Decks must be supported independent of the cantilever. Joists: Joists shall not overhang beams by more than 2 feet. Beams: Shall not extend over the posts more than one foot. Beams must be a minimum of 2 members, bolted, lag screwed or nailed together. Load Requirements: Decks shall be designed to support a live load of 40 pounds per square foot. Setbacks: Please call the Building department to verify what your setbacks are from the property lines. Stairs: Risers are a maximum 7 ¾ high with the maximum difference of 3/8 in height between them. The treads are a minimum 10 long. Cantilevers: All house cantilevers are not designed to support a deck. It either needs a header with joist hangers or additional posts and footings to support the deck. See illustration.
EXAMPLE SITE PLAN On the diagram below: Fill in the dimensions from the property line for the deck location and size. Provide one (1) copy of a Site Plan (on Registered Land Survey or County Plat Map) Show on Plan: Lot lines Lot dimensions Street name Address Owner name(s) All existing structures Driveway Pond/Lake/Stream Special easements Power supply Location of new structure Structure distance to lot lines Distance to other buildings *For townhomes please include the dimensions to adjacent units NOTE: If Site Plan is incomplete, the plan review process will be delayed Gopher State One Call (for utility locations) 651-454-0002
PLAN VIEW HOUSE LOCATION Show length and width of deck. 1. One foot maximum beam cantilever. 2. Joist size and spacing (on center). 3. Two foot maximum joist cantilever. 4. Indicate size & location of posts, number of beam members (minimum 2) and footing size. 5. Joist span-see table. 6. Minimum deck thickness (2x6, 5/4 x 6, etc.). Space between deck boards 1/8 minimum. STAIRWAY REQUIREMENTS
RIM JOIST ATTACHMENT DETAIL HOUSE CANTILEVER DETAIL Alternate cantilever framing: Install 2 posts with footings and a beam to support deck at cantilever.
GUARDRAILS AND DECK SECTION DETAILS
HANDRAIL DESIGNS 1 ½ minimum space between handrail and guardrail or wall. Decay resistance wood required.. Alternate profiles may provide equivalent graspability.
JOIST SPANS