Thread: Deck help
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Old 07-09-2018, 11:26 AM
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EZM EZM is offline
 
Join Date: Jul 2010
Location: Edmonton
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Quote:
Originally Posted by Feener86 View Post
For a deck that extends 20 ft from the ledger you would need 2 beams no matter what using dimensional lumber. Which means from what you are saying or what Im understanding you are about 8 pc 2x8x8 and 2 pc 2x8x14 short of building the deck. (using 16o/c joists). I assume you would be using 5/4x6 materials for decking.
For this you need at least 4 piles and posts and depending on the amount of weight you intend to put on the deck but I would normally use 3 posts per beam.
As mentioned before I think you need to get some professional help or at least have a pro draw it out for you with every detail so you dont cost yourself more money. Details that would also include doing the ledger and flashing properly so you dont rot out your house exterior prematurely or leave an issue for the next owner.
Just my 2 pennies...

Also, if you have a plan of some kind from rona maybe a pic would help, but in my experience they never account for double joists at the ends for railing or "picture framing" the decking nor the mid span blocking required. Which is why understanding all the details and having your own material list is always better then guessing how someone else might put it together ( properly or not)
100% agree ....

2x8, using 16" O.C. will span anywhere from 10'-8" and 14'-2" depending on how your load rating pertains to your jurisdiction's building code (from 30 to 60 lbs per live load ft2).

Your drawings (assuming you obtained a permit) will include your span and cantilever detail. Most jurisdictions will require a permit for any and all structures secured to your home in excess of 100ft2 regardless of height. Height requirements often only pertain to the requirements surrounding rails and stairs. Either way .......

Typical cantilever allowances (at least here) are max 24" - so a 20' run out would equal a span from your ledger to your furthest out support beam which supports your joists is min 18'. That means you need 2 support beams if your joists are 2x8.

These 2 beams will run paralleled to your ledger.

In your case, your support beams will be placed at 18' and 9' out from the house.

A 2x8 @ 16" O.C. will allow you to span that distance.
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