[m98cox]

Storage loft in 22' high garage.
I have a really high garage and want to build a 5' X 18' storage loft.
I have two 2x6x20 grade 1 treated wolmanized southern pine boards and was thinking about using those for my span across the garage, 18'. I was going to use 2x6 joist on 24" centers, cantilevered. I have two 4x4 grade 1 post that I was going to place on each end and mounting the 2x6 ledger to the post by notching out 2" of the post.
I don't expect to place a lot of load on this.
Will this work, or, do I need another 4x4 post in the middle at 9'?

Thanks for any suggestions!

 

[Gary in WA]

2x6, #2 doug/fir spans 8'1" with 40#live load, 10# dead load, per square foot. With reductions for Pressure Treated, and Southern Pine. Ask your supplier how much.

I would use a post in the center, with post caps and bases on all, for earthquakes.

http://www.strongtie.com/products/Category_list.html?source=topnav Be safe, GBAR

 

[Scuba_Dave]

Agreed, even with the #1 wood you have 2x6 will only span Max around 12'+ for light loads
And that's a rating for a floor joist, not a support beam
Definitely a post in the middle

Where are you located?

 

[CrossWorks]

Just what Dave and GBAR said:

Try this suggestion:

>I would add one more joist in the middle to make up for the 5' span
>Then span a 4 x 6 under your 3 joists
>Place a 4 x 4 at center of the 4 x 6
>And install [4x4] 45 degree angled support starting at 6" in from each end

all of this at the 9' location.

 

[Scuba_Dave]

I was just re-reading & re-thinking
Are you thinking of canti-lever due to a vehicle that needs to be pulled in under the shelf?
How much of a canti-lever?
How high off the floor will this shelf be?

I would go 16" OC
With a 5' deep shelf you will find that you will be on that shelf moving stuff around
A 24" OC is fairly weak as far as supporting a person's weight IMO
You really don't want it to give way while you are up there

I was thinking that one end at least would be against a wall of the garage
But you state you will put a 4x4 post at each end
Can you give us an idea of where this will be located in the garage?
It will be much "stiffer" if one end is firmly attached to a garage wall ( in addition to the back)

 

[m98cox]

Well, I built it, and the wife has already loaded it up with 'once per year' storage items, christmas, thanksgiving, etc.
Like I said, I have a high garage, 18' ceiling, yep, talk about wasted space.
So, the dimension is 5'X20' and it is 8'6" high. I used a 2x6 ledger board on the back screwed into the studs of the wall every 16". I used 2x6 joist on joist hangers with 16" OC. On the front side I used two 4X4 post on each end at the/against the wall on each side. I ended up using the joist hangers on the front and back instead of the cantelever. I did place one 2X4 in the center. Screwed plywood to the top for a floor. All lumber was grade 1 pressure treated. Seems pretty stable. Even after loaded, the joist don't seem to be straining in the hangers. I would guess I might have about 800lbs on it. BTW, live in Va.