second floor support.

[Dave Maxwell]

Building a second floor in shop. First part will be 42x12. One wall is the outside wall running the 42 span. Have an overhead door on one end. What size wood supports do I need and is 16 centers good. Thinking a 2x8 across back wall. Its a pole building and there is 9 foot centers. Would the 2x8 support the load if nail to the face of the poles? Will be storing stuff on top as well as walking

 

[Jinks]

Best bet is to talk to an architect about loads, but if it's just going to be storage you *may* be able to figure it yourself. 16" centers should be fine for floor joists, but for anything load bearing I'd be thinking 2 2 X 12's with plywood sandwiched between them. I'm assuming you're talking about a second level storage area. When I added a second floor to my house it was supported by 16" gluelam beams, & several of them!

 

[wssix99]

You are looking to build a mezanene, right? (Not connecting anything to the building walls/structure.) If not, then you will need an engineer to confirm your walls can take the loads.

I'd look for a local deck building guide, which you can use to look up all the members needed for various loads.

 

[jetnow1]

A nailed on ledger board is wrong and dangerous. The proper attachment would be lag bolts at a minimum, better would be through bolts.

 

[Cyberbear]

When building my 30 x 80' shop with 12' walls, I had a second floor/ceiling at 8' that was supported at the exterior walls with a let-in horizontal brace under the 2 x 12 joists at 16' o/c. the middle had a stud wall support to hold the ceiling/floor up. So far strong as can be with no problems.

 

[larry_g]

Building a second floor in shop. First part will be 42x12. One wall is the outside wall running the 42 span. Have an overhead door on one end. What size wood supports do I need and is 16 centers good. Thinking a 2x8 across back wall. Its a pole building and there is 9 foot centers. Would the 2x8 support the load if nail to the face of the poles? Will be storing stuff on top as well as walking

If you look at post #11 in my build below you can see how I did it. I used a 2x12 between the posts and 2x10 joists. Note the support block on the post under the 2x12 where it splices at the post. In the center the joists are on a 4x12 that we had left over from another project.

Note on the one end is what I call a storage wall. 2x10 studs that have a cover on one side and shelves on the other.

Good luck

lg
no neat sig line

 

[K'ledgeBldr]

I'm sure the poles were not designed, nor are adequate to carry the additional load. Your best bet is to make it free-standing using 4X4 steel posts with mounting plates, LVL's or GluLams will give you wider free spans, joist sizes will be determined by span and load.

 

[Dave Maxwell]

The post are 3 2x6 together. They are in concrete. Will that be strong enough if I also put 2x6 on 16 c/l between the post

 

[Jo Diesel]

No a 2x8 nailed to the poles is not even close to strong enough. You are going to want to build a 2x6 wall to go inside of poles 16" on center and then use 2x10" on 16" on center to span 12' with a 2x6 wall on the other side.
Don't kid yourself to think there will be no real weight up there. Most things do not weigh very much when you carry them up one at a time.

 

[Dave Maxwell]

I plan to use a 2x10 board all the way between the 9 foot centers of poles nailed to 2x6 studs going across at 16 c The 2x10 will be lag bolted to the main poles. 3 2x6 studs

 

[Dave Maxwell]

I plan to use a 2x10 lag bolted to the post and attached to 2x6 that will be 16 on center between the post

 

[K'ledgeBldr]

So, you're saying you're going to frame a 42' long stud wall against the current exterior wall to support this upper floor?

If so, you don't need to use 2X6's. You can use 2X4studs 16oc with no problems. You can "tie" the wall to the posts to prevent movement/racking. If there's any doubt as to the amount of "stuff" you plan to put on this floor go 2X8's 12oc, or 2X10's 16oc- #2 or better.

Now the question remains- how are you going to support the other end of the floor? Another stud wall; or some open spans?

 

[Dave Maxwell]

Plan to build a 2x6 stud wall on opposite side.

 

[K'ledgeBldr]

Again, no need for 2X6's- that's just a waste of money for what you're wanting it to do.
Same reason I mentioned 2X8 or 2X10; sometimes you'll get a better deal going with the 2X8's than the 2X10's (42 versus 32 joists)- price and quality.

 

[Dave Maxwell]

Eventually there will be more rooms added. Total plan is off that wall to have one 25x25 room upstairs as man cave and 15x25 upstairs storage over paint booth. At the end of the 25 there will be a 10x30 foot mezanine on each side going to front wall of building. These are for main parts storage

 

[Dave Maxwell]

OK so when I set the floor joist on. I plan to run 2 boards flat on top of the wall studs. Do I set a rim board on top of the flat boads and then use the metal brackets to attach the joist? If so, what do I do to mount rum board. Assume it is flush with outside of wall which is wall for another room. Do the joist hold it in place plus the floor boards on top or is it toe nail to the header boards?

 

[Firebrick43]

Rim joist is attached mainly to the joist to prevent racking or the joist from all falling over. It's alright for it to sit on the wall. You don't need joist hangers as long as some of the joist sit on the header. You could toenail the joist to the top header of the wall but some metal strapping would be stronger and a better solution. Take and nail the strapping to the bottom side of the header or even better the studs themselves. The studs may be hard to do if it's the wall against the existing wall. Run the strapping up and over the rim joist and back down to a stud on the inside. Use the short fat nails for strong tie plates and make sure they are in shear only.

 

[Dave Maxwell]

Thank you. Cleared up alot of confusion.

 

[Dave Maxwell]

 

[Dave Maxwell]

Have filled in between the post yet.

 

[theoldwizard1]

How are those beams (the long board that the joists connects to, sometimes called a rim joist) attached to the post ? Nails or lag bolts are inviting failure. Through bolts are better, but not best



They should be "set in" to the post. Also those beams should be a a couple of sizes larger than the joists, like 2x10 or 2x12 depending on the distance between the posts and the load you are going to have on your mezzanine.

If you don't want to start over with a larger, inset beam, take a 2by the width of the post and force it between the bottom of the beam and the floor, assuming you have a concrete floor. Plain wood should not rest on concrete, so cut a chunk of PT and put it between this post "add-on" and the floor.

Because your beam is so undersized, I would also add a post mid way between the 2 existing posts. Cutting the span in half will make a huge difference in the load capacity.

This is all "seat of the pants" and it still probably would not pass a building inspection.

 

[Dave Maxwell]

Did use lags. I like the through idea better. I am going to put studs on 16 c between the post. I will put a post under the 2x10 also. Didn't know about needing a bigger rim than joist. I am going to make a 25 foot span. The I joist say they can handle it. Is there better besides steel. It will be a man cave upstairs, so it will need to be strong. Should I make the load wall out of something bigger than 2x6? My house has 2x6, so I assumed it was strong

 

[bczygan]

What is your live load for the different areas?

Bill

 

[Dave Maxwell]

This area will be storage for Christmas decorations and stuff like that. The other area from what I've read. Live load of 50. If I remember correctly it said normal house is around 40. So I went with 50 for extra security

 

[bczygan]

This area will be storage for Christmas decorations and stuff like that. The other area from what I've read. Live load of 50. If I remember correctly it said normal house is around 40. So I went with 50 for extra security

Bill
Excellent!

So good to hear that you are actually engineering this. But as mentioned above, the devil is literally in the details of how connections are made, how things are fastened, lateral support, etc.

Sounds like a great space.



Bill

 

[Dave Maxwell]

I m open to any suggestions. I want this to be right when the cave is built. Will be family room as well. My kids will be up there. Trying to figure out if I can split the 25 span with a support below. It's my working shop, so not sure if I have room for a post in middle of area.

 

[bczygan]

I m open to any suggestions. I want this to be right when the cave is built. Will be family room as well. My kids will be up there. Trying to figure out if I can split the 25 span with a support below. It's my working shop, so not sure if I have room for a post in middle of area.

Don't quite understand the layout, but if it's a 25' span for a beam, the contributing load can be figured and it can be sized. Probably end up a double LVL.

Bill

 

[Dave Maxwell]

Thst is the layout for upstairs.

 

[Dave Maxwell]

If the lvl says 23.5 foot span. What is the calculation if it's two together?

 

[bczygan]

Calculate the contributing area and multiply by first the live load for one answer and the the total load, for the other answer. Both answers will be in PLF (Pounds per lineal foot).

Go to the tables for a strength of LVL that is readily available (Menards carries 1.9) And look up an LVL that will carry at least half the live and dead loads at the required deflection limits (Probably L/360).

All this is really preliminary design, to allow pricing, and should be checked by a pro.

Bill

 

[Dave Maxwell]

Hoping to get a friend's Dad involved to check out plans. He is in his 80's though so been trying not to.lol

 

[Dave Maxwell]

Thought maybe put a set of 3 2x6 together into a beam across the middle of the room with a center support or support on ends

 

[Dave Maxwell]

Missing post. Odd

 

[Dave Maxwell]

Did you remove your comment or something go hay wire

 

[theoldwizard1]

Did use lags. I like the through idea better. I am going to put studs on 16 c between the post. I will put a post under the 2x10 also. Didn't know about needing a bigger rim than joist. I am going to make a 25 foot span. The I joist say they can handle it. Is there better besides steel. It will be a man cave upstairs, so it will need to be strong. Should I make the load wall out of something bigger than 2x6? My house has 2x6, so I assumed it was strong

First, I did not know those were 2x10s ! If you change the lags to through bolts (washers on each side) AND put 2x6 studs under the rim at 16" O.C you are good !

Your supplier for the I-joist will tell you what size to buy for a 25' span.

 

[Dave Maxwell]

Thank you