Pushing the budget..

[paulharvey]

Let me give some feedback and clarification- this pole barn uses one type of truss, and the true height from the crete floor to the bottom of the truss is their advertised wall height. So, it would indeed be 12ft or 14ft clear height. The footprint can't really get any larger, so that is why I'm wanting to go higher. I think a likely route will be that I will do the 14ft increase now, and just not do any concrete until after the barn is finished.

2 reasons: One is that the ground hasn't been cleared due to weather in SC. I think it would be wise to let the ground settle for a solid month before the concrete is applied. The second reason, is that I'll cut the middle man out (why the crete is so $$?), and give me a chance to know what thickness I need. But it does sound like 5in would give me a 'warm and fuzzy' that I should be able to place anything on the floor in the future.

Anyone disagree to just hold off on the crete until after the build, and deal directly with the crete company? The other issue is that prices on crete are supposed to increase in the new year?

Concrete won't shouldn't increase much fuel prices are still real low. I wouldn't worry about letting the ground sit before pouring concrete you'll have to compact it regardless. It is harder to pour concrete inside a building just from the standpoint of getting a truck around it and screeding

 

[ovrszd]

In my experiences site preparation is much more important than the thickness of the concrete. I wouldn't consider pouring on fill unless it has been properly compacted.

 

[Stimw]

I would tell them to stick the fiber where the sun doesn't shine!
I had a 40' X 65' slab poured 15 years ago and they bragged that with fiber I didn't need re-bar or road mesh.
I can show places where the concrete has cracked and heaved over 1" and the ground was compacted.
Pics are of slab and 40' X 60' X 14' building I had put up in May. Concrete guys were FIRST CLASS! Slab is perfect, I have done concrete work and have even driven the trucks.
Pic was taken before they added mesh placed on chairs then poured.

 

[Streetcar]

I would tell them to stick the fiber where the sun doesn't shine!
I had a 40' X 65' slab poured 15 years ago and they bragged that with fiber I didn't need re-bar or road mesh.
I can show places where the concrete has cracked and heaved over 1" and the ground was compacted.
Pics are of slab and 40' X 60' X 14' building I had put up in May. Concrete guys were FIRST CLASS! Slab is perfect, I have done concrete work and have even driven the trucks.

Pic was taken before they added mesh placed on chairs then poured.

Stimw
If your slab heaved over an inch , you have either a subgrade or drainage problem.
Fiber is great for stopping cracks in thin concrete slabs

 

[paulharvey]

Stimw
If your slab heaved over an inch , you have either a subgrade or drainage problem.
Fiber is great for stopping cracks in thin concrete slabs

I was thinking the same thing, about heaving or settlement.

Fiber is for controlling cracks from curing, which should be minimal if you cut with in 24 hours of pour, and don't soup it up with too much extra water

 

[s219]

If this is a pole barn with standard skirt, they wouldn't pour the floor until after the barn is up anyhow, so it can't hurt to wait. However, make sure you have a dependable concrete guy lined up to do the work. I had a heck of a time getting someone to do my barn floor. It was to the point where I was ready to have the concrete truck show up and and do the finishing myself, because I was sick of dealing with flakey contractors. Finally called the contractor who had given me an early, timely, but high bid, and they came out and did it. I paid about 25% more just to get someone who would show up when agreed and do the job.

One holdup was that I couldn't finalize installation of the sliding doors until the floor was in, so the concrete baloney was screwing up the rest of my plans. The barn was built in about 3 days, and then I wasted weeks waiting for the concrete floor.

All that is a way to say that if you have a reliable, trustworthy, dependable plan to get the floor put in at a time that fits in well with the barn construction and its completion and future use, do it, and don't wait. Once the floor cures you can move into the barn and start using it. Would be a pain to have to move everything out to pour a floor later on.

Also, going back to the pole barn, normally you want to have the site leveled and prepped before they begin construction. In most cases, the grade needs to be within about 6-9" of level across the whole site. While doing the grading, you're also laying the groundwork for the floor. In my case, I built up the grade and compacted it over a couple weeks well in advance of the barn construction. When the barn builders showed up, they drilled their post holes and built the barn. Afterwards, I used my tractor to carefully level out the post hole spoils inside the barn, put down gravel to bring the grade level up to 4" below the final floor height, and use a plate compactor to settle everything into place.

 

[Cord]

If the fiber concrete is in stead of rebar from my experience that would be a poor choice. I would have a rebar grid and up the strength of the concrete and stick with a 4" floor.

Second that. The micro fiber is only good for shrinkage cracking. I'd spend the money on getting a 3x3 grid of #4 bars in the 4" 4,000 psi slab. If the mat is too expensive because of the labor, then look at a macro fiber or steel fiber. The problem with those products is that they stick out of the slab and make finishing difficult.

I'd go higher with the building. 12' of clearance really isn't enough because it forces you down to a 10' door. Also, with additional height you have a chance to put wing additions on at a later date. Yes, if you build it you'll fill it. A 30x50 building fills up pretty quick.

 

[USAFpj]

Guys, I think I'm going to pull the trigger and get both done at the same time. I've always received sound advice from the gents at TBN, so when guys say to do it the way you want the first time, I better listen! Whether needed or not, I reckon I'm going to go with the 5in concrete (never know what I'm going to store in the future. The 14ft height is not just for me, but a dedicated storage place for my Dad who lives about 300yds from me. I think I'm squabbling about $3.5K over a $40K building, so I'm sure I'll forget the cost once the last check is written.

 

[EddieWalker]

I'm not a fan of fiber. It's ok for what it does, but it does not replace rebar. When added to the mix and you are using rebar, it will help even more at reducing cracking, but nothing stops cracking. Concrete will get hard and it will crack. Nothing will stop this. Rebar holds the concrete in place so when it does crack, you don't notice it. For this to happen, rebar needs to be inside the concrete. Not on the ground, which is why chairs are used to keep it in the middle of the pour. Wire mesh does the same thing if it's kept in the middle, unfortunately 100% of the time that I've seen it, and in ever single picture that I've seen it done on here, it's laying on the ground and next to worthless. You cannot walk on mesh and pull it up into the middle of the pad, and walk on it some more and expect it to stay in the middle. Totally impossible to do this. Mesh should only be used on small pours when nobody walks on it like sidewalks.

The difference in strength from in thickness isn't going to be very significant. I'd just as soon add another sack to the mix and raise the psi higher that way.

 

[ovrszd]

I'm not a fan of fiber. It's ok for what it does, but it does not replace rebar. When added to the mix and you are using rebar, it will help even more at reducing cracking, but nothing stops cracking. Concrete will get hard and it will crack. Nothing will stop this. Rebar holds the concrete in place so when it does crack, you don't notice it. For this to happen, rebar needs to be inside the concrete. Not on the ground, which is why chairs are used to keep it in the middle of the pour. Wire mesh does the same thing if it's kept in the middle, unfortunately 100% of the time that I've seen it, and in ever single picture that I've seen it done on here, it's laying on the ground and next to worthless. You cannot walk on mesh and pull it up into the middle of the pad, and walk on it some more and expect it to stay in the middle. Totally impossible to do this. Mesh should only be used on small pours when nobody walks on it like sidewalks.

The difference in strength from in thickness isn't going to be very significant. I'd just as soon add another sack to the mix and raise the psi higher that way.

I hate to even mention this as it will jinx me and my floor will crack like glass!!!

My 7 year old 6" 42'x50' rebarred shop floor has no cracks big enough to be visible. I power wash it a couple times a year so would see any visible cracks. It's cut in 10' squares. The cut lines are filled. So I guess it could be cracked in them and I wouldn't know it.

As to adding an inch to a 4" floor, wouldn't that increase it's strength by 20%?? If not, then why pour more than 4" in any floor?