2nd story deck


  #1  
Old 01-29-03, 12:15 PM
jimjolicoeur
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2nd story deck

Need to find the beam size for a 15x25 deck. The span is 25' without a post in the middle. Deck is from master bedroom to a 2nd story pool deck.
 
  #2  
Old 01-29-03, 07:16 PM
L
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Check with your local bldg. dept.

You can find a beam that will span 25' without a post, or POSTS, in the middle. (Notice I didn't say that you would like the price!!)

You can support that beam with just 2 posts, PROVIDED the posts are large enough to support the beam, and anchored well enough to support that beam and the deck above it that is at least 8' above grade in the seismic zone you are in.

It can be done that way, but you will probably have about as much money invested in the deck as you do the rest of the house!!
 
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Old 01-30-03, 09:01 AM
brickeyee
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For outdoor use you are probably going to need steel for this span. Gluelams and all the other products you have heard about are not usable outdoors. You are down to large timbers (talking 18-24 inches here), or steel (and it will be very heavy and require a very solid foundation to prevent sinking). The existing deck and building will not be able to support the weight of either wood or steel members so they will require seperate support.
 
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Old 01-30-03, 05:55 PM
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We haven't really mentioned the footings for those 2 posts yet. You are in CA -- that puts you in AT LEAST siesmic zone 3. Then you will have to meet whatever the wind load requirements are for your area, and any snow loads that may apply.

How large of footings you would actually need are is info you will have to get from your local bldg. dept. But, I can get you started thinking in the right direction. I just installed an aluminum patio cover, spanning only 8' between the posts, in an area with a 10 lb. snow load (the minimum my engineering covers), 80 mph wind load, in siesmic zone 3. I had to embed each of those posts in footings that were 24" square and 42" deep (the posts went 36" down into the concrete).

What you are talking about doing here, it wouldn't surprise me in the least to find out that you might need footings 4' to 5' in diameter, and 6' or 8' deep, with whatever posts you have to use embeded all but the last foot or so into those footings. Do the math -- THAT is a lot of concrete!!

It can be done, but it will be one very expensive deck.
 
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Old 01-31-03, 09:59 AM
jimjolicoeur
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Would I go to a architect or a engineer for a set of plans? And if a engineer, what kind?
 
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Old 01-31-03, 11:22 AM
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jimjolicoeur,

I would suggest that you seek the services of a Structural Engineer, BUT it may be wise to seek an Architect who will probably be working with a structural engineer in preparing blueprints needed for the required permit. For what is being talked about here, you will need those services to get required permits.

Hope this helps!
 
 

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