Building Question
#1
05-05-15, 06:47 PM
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Building Question
I'm building a 24x16' shed.
I'm putting down nine piers 8" in diameter and plan to use Simpson strong ties combined with 4x6 PT.
The piers will be in rows of three each 24' ft. long. A pier at 0 - 12- and 24'.
On the pier at 12', I'd like to join two 12' 4x6s using the strong tie.
Is there any issues with this?
I'm putting down nine piers 8" in diameter and plan to use Simpson strong ties combined with 4x6 PT.
The piers will be in rows of three each 24' ft. long. A pier at 0 - 12- and 24'.
On the pier at 12', I'd like to join two 12' 4x6s using the strong tie.
Is there any issues with this?
#2
05-05-15, 06:56 PM
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Are you using the Simpson adjustable post bases? They have a base plate that raises the post off the concrete, so if 2 posts are sharing one Simpson post base, each would be half on, half off. You might want to through bolt both those 4x6's together with some 1/2" bolts and put some galvanized steel shims underneath the sides of the posts that may be in mid-air.
#3
05-05-15, 07:04 PM
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Yes, using the adjustable post bases. But the posts aren't posts, they're beams (laying not standing up).
One end supported fully by a strong tie, the middle sharing a strong tie.
One end supported fully by a strong tie, the middle sharing a strong tie.
#4
05-05-15, 07:19 PM
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I see. That makes sense. I don't know your whole plan, but if this is the foundation for a floor, it sounds like your 4x6's on the ends may be overspanned. From the info below, it would seem they should only span about 7' between piers (not 11.5'). If you are laying joists perpendicular on top those 4x6's those joists will span roughly 7.5' from beam to beam which means you have a lot of floor area on those poor 4x6's.
https://www.ci.richland.wa.us/Docume.../Home/View/141
The 4x6 in the middle will definitely be overspanned since it will have more floor area bearing on it than the end beams will.
This source would recommend 4x12's. http://decks-ca.com/Deck_Beam_and_Post_Sizes.html
https://www.ci.richland.wa.us/Docume.../Home/View/141
The 4x6 in the middle will definitely be overspanned since it will have more floor area bearing on it than the end beams will.
This source would recommend 4x12's. http://decks-ca.com/Deck_Beam_and_Post_Sizes.html
#5
05-05-15, 07:26 PM
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They are the two outer and center beam for a floor. They will be tied together with hanging 2x6 s 16" OC front to back.
All the research I did indicated this was plenty.
All the research I did indicated this was plenty.
#6
05-05-15, 07:35 PM
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Yes, that's exactly what I imagined when you said they were horizontal beams. It's definitely not "plenty". But since that wasn't part of your original question, I won't belabor the point. But you did ask if there were any issues. If you wanted to use 4x6's, those concrete piers down the center beam should be spaced approximately 5' on center... 0, 5, 10, 15, 20, 24... not 12' on center. While the end beam piers should be spaced a maximum of 7' apart. 6' would be a good number to shoot for.
#7
05-05-15, 08:08 PM
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Thanks for pointing this out. I have no idea how I got stuck on 4x6s. I just looked up the info I researched and sure enough - 16x 24 with 8 ft pier spacing equals two 2x12s, or a 4x12.
Thanks again.
Now that we've cleared that up, are we on the same page about using the same strong tie to support both ends of the 2x12s in the middle? Is that acceptable?
Thanks again.
Now that we've cleared that up, are we on the same page about using the same strong tie to support both ends of the 2x12s in the middle? Is that acceptable?
#8
05-05-15, 08:19 PM
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Yes, I think that's fine. As long as the total load doesn't exceed what the tables say.
ABA/ABU/ABW Adjustable and Standoff Post Bases
You might want to add an additional connector above the post base just to keep the two pieces aligned.
ABA/ABU/ABW Adjustable and Standoff Post Bases
You might want to add an additional connector above the post base just to keep the two pieces aligned.
#9
05-05-15, 10:14 PM
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On the side of each 2x12, not the top correct?
Plywood will be keeping the tops connected if laid 8' x 3 vs. 4' x 6
Plywood will be keeping the tops connected if laid 8' x 3 vs. 4' x 6
#11
05-06-15, 04:28 AM
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Sides or top. I'd probably slap a small mending plate on each side since that would be the easiest way to align them. (MP14 or MP24) But if you want it to be hidden, it could go on top.
Glad to help.
Glad to help.
#12
05-06-15, 11:33 AM
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With the top of the two 2x12's being covered, is there any concern for sandwiching them with no gap in the center? It seems if I space them in the center it will lessen the load bearing capability.
#13
05-06-15, 12:33 PM
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Since I completely overlooked a core component with the floor beams, I figured I'd show the floor plan to make sure I'm not missing anything else in the design.
Always open to suggestions.
Always open to suggestions.
#14
05-06-15, 12:48 PM
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Minimum width for footers will be 12". You can accomplish this by doing what is called a double pour. I usually dig a 18" round hole 24" down and dump in at least 80lbs to 100lbs of concrete with a section of rebar driven into the center of the hole, through the concrete and into the earth. Leave enough rebar protruding to get a good grab on your 8" tube with concrete that you will set over it and make a second pour up to your desired height.
#15
05-06-15, 01:02 PM
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Thanks czizzi.
Help me understand this. I looked at a lot plans that build this type of structure on skids laid and leveled on dirt, or pier blocks placed on level dirt. I thought digging past the frost line and dumping in 8" diameter concrete was going above and beyond.
The highest point will be ground level (no tube/concrete above ground), with the lowest point being only 4" down (tube/crete 4" above ground).
Help me understand this. I looked at a lot plans that build this type of structure on skids laid and leveled on dirt, or pier blocks placed on level dirt. I thought digging past the frost line and dumping in 8" diameter concrete was going above and beyond.
The highest point will be ground level (no tube/concrete above ground), with the lowest point being only 4" down (tube/crete 4" above ground).
#16
05-06-15, 01:17 PM
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Around here, anything over 200sqft requires a permit and needs to abide by standard building practices. You are building a garage, not a shed given the size at 16x24. It needs appropriate anchoring and footing. I also would rethink your pier height as you need both air movement under the floor structure and the 2x12's are not rated for ground contact even though they are pressure treated.
Your skid barns/sheds are built much lighter but are also required to follow the permit process for those over a certain size. Undersized, they just drop and go as no one will be checking behind them.
Your skid barns/sheds are built much lighter but are also required to follow the permit process for those over a certain size. Undersized, they just drop and go as no one will be checking behind them.
#17
05-06-15, 01:58 PM
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My initial response is I just want to build it so it's sturdy and safe. I don't care about code on this one. To which I would think your response is going to be code is in place to ensure sturdy and safe.
Makes sense. Until I read your last line that clearly says in other words if no one is checking people are building, and selling, buildings that aren't to code because no one is checking.
I do appreciate the suggestions, and I would like to keep receiving them. But I'd also like to know what's acceptable and what is code. There is a difference.
RE: the height - raising the highest pier 1" so it is not in contact with the ground is not an issue. Nor would removing some dirt instead.
RE: the piers - I have a gas powered auger so enlarging the hole a few inches is not a big deal. But is it really necessary?
Makes sense. Until I read your last line that clearly says in other words if no one is checking people are building, and selling, buildings that aren't to code because no one is checking.
I do appreciate the suggestions, and I would like to keep receiving them. But I'd also like to know what's acceptable and what is code. There is a difference.
RE: the height - raising the highest pier 1" so it is not in contact with the ground is not an issue. Nor would removing some dirt instead.
RE: the piers - I have a gas powered auger so enlarging the hole a few inches is not a big deal. But is it really necessary?
#18
05-06-15, 03:12 PM
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Makes sense. Until I read your last line that clearly says in other words if no one is checking people are building, and selling, buildings that aren't to code because no one is checking.
I don't write the codes, they are readily available for you to check. Minimum footer width is 12". It is the same for buildings as it is for decks. I don't know where you are located, but a building that size most likely requires a permit. Permits are there to protect everyone. Not just you, but the person that buys the property long after you have moved on, or anyone coming to visit you and happens inside the structure.
You can read up on footers with regards to decks here, it will mimic what you need to do for your building. http://www.awc.org/publications/DCA/DCA6/DCA6-12.pdf
I'll even correct myself as for decks, the round minimum footer is 18" and sonotube minimum is 12" unless you have a square footer then 16"x16" is minimum.
#20
05-06-15, 04:47 PM
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Only mention is his drawing states 18" frost Line/depth. So he is at least my latitude (Southeast Virginia) or lower.
#21
05-06-15, 05:14 PM
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I see.
Yeah if it was me I'd probably use the 12" sonotubes and just use a spade to flare the bottom out to 18 to 20", doing the double pour like Czizzi mentioned with the rebar cage. Before the footing completely sets up, i would insert the sonotubes into the wet concrete and level them all with a transit. Pretty important that they all be level. I agree the tops of those posts should all be above grade... I would go at least 2" above since soil has a way of rising.
In one local municipality they will allow up to 14x16 on a pad with no footing. Found that out cuz I need to help a buddy build a shed/workshop sometime soon.
Yeah if it was me I'd probably use the 12" sonotubes and just use a spade to flare the bottom out to 18 to 20", doing the double pour like Czizzi mentioned with the rebar cage. Before the footing completely sets up, i would insert the sonotubes into the wet concrete and level them all with a transit. Pretty important that they all be level. I agree the tops of those posts should all be above grade... I would go at least 2" above since soil has a way of rising.
In one local municipality they will allow up to 14x16 on a pad with no footing. Found that out cuz I need to help a buddy build a shed/workshop sometime soon.
#22
05-06-15, 05:24 PM
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I'm in Oregon.
I'll be using the 8" sonotube.
I did as suggested and flared the bottoms out 4". I will also do as suggested and use the 2 step pour, and also pound the rebar into the ground with enough extra to run into the 8" tube after the footer sets up.
Hole depth is about 28". I'll raise the highest point 2" above ground.
I'll be using the 8" sonotube.
I did as suggested and flared the bottoms out 4". I will also do as suggested and use the 2 step pour, and also pound the rebar into the ground with enough extra to run into the 8" tube after the footer sets up.
Hole depth is about 28". I'll raise the highest point 2" above ground.
