Building Homes or Extensions/Outdoor music stage


I need to build a 30' x 40' permanent outdoor music stage 2' tall capable of handling 150 psf. I want to use 6"x6" footers in concrete. I need to know the spacing of the footers, what size joists (2 x 10?) assuming I am using 3/4" plywood for the top of the stage.

Hi Michael, rule of thumb for beams 4x? is one inch of height per foot of length of span.  In other words a 4x4 spans 4' a 4x6 6 feet etc.  It is similar for joists spaced on 24" centers..a 2x10 will span ten feet ,  2x8 eight feet etc.  Your post/column spacing would be determined by the beam size and span capabilities.  A 2'x2' x12" deep concrete pad will suffice for your column pads.  Or you can buy precast column post pads for this purpose. Your deck is 3/4" plywood preferably tongue and grooved.  If you need to pour a supporting wall footing around the perimeter 12" wide by 8" thick if the wall will support the deck edge.  At least one continuous #4 rebar for reinforcement.  I hope this information helps, sorry it took a while for me to answer, I'm in the middle of remodeling a large cathedral and haven't had a lot of spare time.  Sincerely Bruce Johnson

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Bruce E. Johnson


I can answer any construction related question in regards to carpentry, concrete, drywall, masonry, structural elements of any type of building, residential or commercial. Interior or exterior.


Custom Commercial and residential buildings. Churches, theaters, schools and auditoriums. Most recently I am working with the Catholic Church on several design build committees. I have a website related to scheduling and project supervision. Although my expertise is more related to multimillion dollar commercial, educational and theatrical projects my generous credentials in residential and remodelling construction make me a viable source of information regarding all forms of building questions.

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