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beam spans for different sizes?



i have nine 6x6 posts in the ground and am ready to build

the total area is 20 sq ft. (outside corners of posts)

the height is 2 feet above ground.


from the outside of the outer post to the middle of the inner posts is equal to 10'


img for ref


I was wondering if i could use 3 double 2x6 as support beams, or if that would not be enough.


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Posted 2012-08-21T14:55:43+0000  by NerdrageIMO NerdrageIMO

do you know how much it would cost thru home depot? and how muc the delivery fee is?

i live on the tulalip indian reservation so if i order in store i shouldnt have to pay sales tax as well.



also: the true distance of space between the posts is ~9'4" 1/4, because the posts are 5 1/2" (6") and there are three rows of three...


so i need some quotes for pressure treated AND structural select (idk if they are the same thing)


im looking at 2x10x20 and 4x10x20 because i want to go flush with the beam and posts then just put a skirt on it.

Posted 2012-08-21T19:24:53+0000  by NerdrageIMO

You'll get a lower price if you were to go with 2x10s instead of 4x10s...4x10s are  considered non-stock size. You don’t have to have an overhang, flush with the beam its fine too.


I don’t know of hand what our exact cost would be ,but I do know it’s going to be the same if not less.


If you find a current lower price on an identical, in-stock item from any local retailer, we will match the price and beat it by 10%.


What is your zip code? 



Posted 2012-08-21T19:55:17+0000  by George_HD_CHI

my zip is 98271 and the tulalip store doesnt have 2x10x20 in stock


currently the lowest price ive gotten was from martin lumber in everett

33.06 for pressure treated 2x10x20s but idk if thats considered local because its out of my city limits.




Posted 2012-08-21T20:30:06+0000  by NerdrageIMO


Thank you, 


Would you be able to e-mail your material list to Store over on 9310 Quil Ceda Blvd. is expecting your e-mail.

Please include your contact info in your e-mail and pricing given from Martin Lumber. They will work on your quote and competitors pricing.


They do not have 20’ lengths in stock but they can order it if you want to.









Posted 2012-08-21T20:57:53+0000  by George_HD_CHI
OK... will do... and just a quickie here...
i was going to do 15 joists 19" apart (except outer/frame joists which will be 6" or less from the previous)

would this be the correct calculations for pressure treated wood sold at home depot? i have some 2x6x10s and they all say structural select. so i assume that the 2x10x20s will be the same.

and to be clear three doubled 2x10x20 beams 10 feet apart would be a sufficient base for a platform without overhang?

last one.
should i go thicker for the outside joists / ledger beams?
eg: 6 joists from center each side then the 4 beams that make the oustside of the 20'x20' frame

lmk if you need clarification.
Posted 2012-08-22T17:27:48+0000  by NerdrageIMO

Hey there NerdrageIMO,


SteelToes is out of the office, but wanted to make sure that your post was followed up on.


As to your inquiry about our lumber being the same as what you found--our lumber is premium select. Now, that may or may not be the same as what the other place you were discussing has. Since it's in a very different area of the US from myself, I can't speak for what they'd have out there.


As to the question on the 2x10x20's...those will work out just fine.


SteelToes will be back in early next week and will follow up with you again to make sure everything is squared away!~


Posted 2012-08-23T16:12:11+0000  by Jay_HD_CHI

is premium select the same as structural select?



Posted 2012-08-23T18:07:11+0000  by NerdrageIMO

when using plywood filler, is it ok just to cut  rectangles that fit and make it 20'?


or does the plywood have to span the entire length of the beams?



im gonna be screwing the beams or bolting them together anyway.

Posted 2012-08-23T23:42:26+0000  by NerdrageIMO

Hey NerdrageIMO,


Sorry I didn’t get back to you right away - i was out of the office.


On your questions; 


Is premium select the same as structural select?


Yes, premium select is the same GRADE as structural select. Premium select or select structural (grading terminology) is the highest grade available in dimensional lumber class. Ours is called premium because of its PREMIUM appearance grade in addition to structural strength. Select comes from being selected for us.


Blocking question;


Blocking does not need to be full length of the board; you can use blocks just where the beam is getting bolted. It does need to be pressure treated like rest of the lumber though.


last one.
should i go thicker for the outside joists / ledger beams?


Use same lumber for the whole project. Additionally make sure to properly flash the ledger board against the house.


Hopefully this answer came back in a timely matter…? How’s you project going anyways? :smileyhappy:Can you post some pictures?



Posted 2012-08-27T14:52:40+0000  by George_HD_CHI

the deck isnt attached to anythign.. its a floating deck. later on i will post some cad drawings of the steps i am going to be making so i may realize the image i have in my head.



what days are you in so that i may streamline my experience on this forum?

Posted 2012-08-27T18:00:12+0000  by NerdrageIMO
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