| Deck building is a polular do-it-yourself project with | | | | Under the right conditions, technically it is alright for |
| homeowners who can take advantage of | | | | beams or joists to cantilever up to 40% of the |
| how-to-do-it clinics and tools rentals at home | | | | distance that they are spanning between supports as |
| improvement retail outlets to construct the decks of | | | | long as the cantilever does not exceed four times |
| their dreams. | | | | the beam or joist depth. An example of this would |
| Cantilevering is a deck construction technique that | | | | be a joist that spans 10 feet between supports. |
| can be used by do-it-yourselfers on almost all decks. | | | | Theoretically it could cantilever .40% x 10 = 4 feet |
| It allows the builder to add several feet to the width | | | | beyond the supporting beam. Thus a 10 + 4 = 14 |
| of the deck without increasing the maximum span | | | | foot joist would be possible. But if the joist is a 2x8 |
| rating for the beams or the joists. This is especially | | | | (with an actual width of 7.25 inches) then the |
| true when homeowners are building bigger and bigger | | | | cantilever would be limited to 4 x 7.25 = 29 inches. |
| decks with more levels and more complex shapes. | | | | Unless you like bouncy construction it would be a |
| In some instances cantilevering makes it possible for | | | | wise decision to limit the cantilever to about 25% of |
| a smaller beam size to be used to support the deck. | | | | supported beam or joist length. An even wiser |
| As far as the joist size is concerned a smaller size | | | | decision would be to never exceed 3 feet of |
| could also be used by the using this innovative | | | | cantilever in the construction of the deck. This will |
| construction method. | | | | result in the deck feeling solid even when one is |
| Another advantage of incorporationg cantilevering | | | | standing over the cantilevered ends. |
| into the construction of a deck is that the location of | | | | Cantilevering more than 3 feet would be better |
| foundation columns, support posts and beams can be | | | | achieved by moving up to the next larger dimensional |
| less precise than in the conventional method of | | | | size of beam or joist. |
| construction. This is an important consideration for | | | | In the initial deck design process it is a good idea to |
| do-it-yourselfers who are not as proficient as | | | | consult with the local building department regarding |
| professional contractors especially in this area of deck | | | | building codes and construction methods. Once you |
| building. | | | | submit your application for a building permit along with |
| However, it is important to remember that there are | | | | your deck design drawings, building department staff |
| still guidelines that limit the distance that a beam can | | | | will make alterations in your design where necessary. |
| extend beyond a support post or that a joist can | | | | Cantilevering can be incorporated into this design and |
| extend past a beam. These guidelines also assume | | | | their expertise will ensure that the deck design will |
| that there will be no unusual loads placed at the other | | | | adhere to construction requirements and result in the |
| end other than the deck occupants. These guidelines | | | | building of an outstanding deck that will meet the |
| are there to provide necessary standards to ensure | | | | needs and tastes of its occupants. |
| the proper and safe construction of outdoor deck | | | | Cantilevering can be an important and very practical |
| spaces by amateurs and pros alike. | | | | part of that process. |