New Workshop - need concrete!

[benjy]

Recently finished our 30x50 workshop, now for concrete.


Before the the bldg was erected (on 18 24" dia x 5' piers), I rented a compactor for the dirt guy who wanted an 4 times what the roller cost me, so I rented it myself & rolled it until dark each day after they left - to their credit, they did roll a few lifts during the daytime.

I've been building industrial facilities for years, even spent time doing every aspect of concrete work (about 30 years ago), so I know what I want, however I'm having trouble finding the right contractor, so I'm considering doing this with my two teenage sons.

A few issues;

1) Any concerns about breaking this up into 4 pours ~10 CY per pour? Anything over 10 CY and I think we'll need more help - I can get a neighbor or two to pitch in.

2) The door is 12x12 and I'm waiting for confirmation on the height of the concrete trucks, if it's close, I could dig out a bit under the door and place that section last. Any other ideas? Buggy / pump? Might need more labor.

3) Will I get a decent finish with a bull float? Or should I rent a power trowel? I do plan on a finish later - undecided between the epoxy/poly/densifying sealer, likely the later due to funds.

4) Any suggestions on how much a finishing crew would cost? I'm pretty set on doing the leveling, visqueen & rebar work myself. I've seen some pretty messed up concrete over the years on the industrial side of things, so I know I want this done right.

5) Think I'm getting in over my head? It'll be a simple workshop - vehicles, woodworking, welding, etc... No major loads or activities.

Appreciate ya'lls thoughts, been lurking for years around here and my project is finally underway.

 

[bigjon]

I’m not a concreter but I’ve helped a lot and done a few small slabs in my life. The finishing for me is the most difficult. The setting up I find within my skill set. You sound like you know what needs to be done. I’d see if you can get an extra couple mates around and do it all in one pour. Get a pump. See if there’s a good finisher that will help. Time is your enemy.

 

[ConCretin]

Let me take a stab at answering your individual questions;

1) Any concerns about breaking this up into 4 pours ~10 CY per pour? Anything over 10 CY and I think we'll need more help - I can get a neighbor or two to pitch in.

Not really. In fact there might be some advantages when it comes to controlling shrinkage. I'd install smooth dowels to at the joints between placements to allow lateral movement and maintain vertical alignment.

2) The door is 12x12 and I'm waiting for confirmation on the height of the concrete trucks, if it's close, I could dig out a bit under the door and place that section last. Any other ideas? Buggy / pump? Might need more labor.

You need more labor. Even if you are are placing in 10 yard sections with a chute, it's a lot of work. Buggies might help if you can't reach with a chute but you lose a man running it. A pump is expensive and a ground line is fair amount of work in itself.

3) Will I get a decent finish with a bull float? Or should I rent a power trowel? I do plan on a finish later - undecided between the epoxy/poly/densifying sealer, likely the later due to funds.

I doubt you'd be happy with a bull float finish. It would likely have ridges and you wouldn't get a hard, dense surface. If you have the ability to run a trowel, get one. You'll want slip on float or combination blades

4) Any suggestions on how much a finishing would cost? I'm pretty set on doing the leveling, visqueen & rebar work myself. I've seen some pretty messed up concrete over the years on the industrial side of things, so I know I want this done right.

I'd expect to pay about $1 sf to have a crew place and finish with a $1500 minimum.

5) Think I'm getting in over my head? It'll be a simple workshop - vehicles, woodworking, welding, etc... No major loads or activities

I'd sub it out. Do the prep yourself but you only get one chance at a flat smooth floor.

Give my Guide to Floor Slabs in the link below a read for some additional thoughts. Good luck whatever you decide to do and congratulations on your project

 

[ArmchairArchitect]

Side question, is that wood siding attached over the metal siding, or instead of? How is it attached?

Looks way better than most metal buildings.

 

[benjy]

I'd install smooth dowels to at the joints between placements to allow lateral movement and maintain vertical alignment.

Love this idea, thanks! If for some reason I do this in parts, I'll be sure and do this.

I'd expect to pay about $1 sf to have a crew place and finish with a $1500 minimum.
I'd sub it out. Do the prep yourself but you only get one chance at a flat smooth floor.

If I can get it placed & finished for 2 grand, I'll be a happy camper, I'll try and go this route. Just need to beat the bushes a bit more and ask hard questions. It is a one-shot deal.

Give my Guide to Floor Slabs in the link below a read for some additional thoughts. Good luck whatever you decide to do and congratulations on your project

Already read through it - many items are already on my concrete supplier spec sheet. Thanks so much for posting this - very clear & concise

 

[benjy]

Side question, is that wood siding attached over the metal siding, or instead of? How is it attached?

Looks way better than most metal buildings.

Thanks!! Yes, it's cedar siding, matching our house per HOA restrictions.

from Lucas Cedar, Willis, TX

A little help with two coats of stain

Using Behr - picked up awhile back to touch-up the house, it's holding up 5+ years so far in a full-sun area

Got up to about 12' working from a ladder. Bldg contractor used OSB on the front, wrapped it and I tried marking the studs so all the lap & gap cedar would screw (stainless) into framing, missed on a few dangit, now those are messing with my 1/2" radiant barrier insulation

Then switched to a knuckle-boom to finish it out, well worth $300 over a weekend. I'll rent this again when I put the first 24 solar panels up on the roof.

Sorry if the photos are too big, still figuring out how to resize some of these things

 

[benjy]

Let me take a stab at answering your individual questions;

1) Any concerns about breaking this up into 4 pours ~10 CY per pour? Anything over 10 CY and I think we'll need more help - I can get a neighbor or two to pitch in.

Not really. In fact there might be some advantages when it comes to controlling shrinkage. I'd install smooth dowels to at the joints between placements to allow lateral movement and maintain vertical alignment.

2) The door is 12x12 and I'm waiting for confirmation on the height of the concrete trucks, if it's close, I could dig out a bit under the door and place that section last. Any other ideas? Buggy / pump? Might need more labor.

You need more labor. Even if you are are placing in 10 yard sections with a chute, it's a lot of work. Buggies might help if you can't reach with a chute but you lose a man running it. A pump is expensive and a ground line is fair amount of work in itself.

3) Will I get a decent finish with a bull float? Or should I rent a power trowel? I do plan on a finish later - undecided between the epoxy/poly/densifying sealer, likely the later due to funds.

I doubt you'd be happy with a bull float finish. It would likely have ridges and you wouldn't get a hard, dense surface. If you have the ability to run a trowel, get one. You'll want slip on float or combination blades

4) Any suggestions on how much a finishing would cost? I'm pretty set on doing the leveling, visqueen & rebar work myself. I've seen some pretty messed up concrete over the years on the industrial side of things, so I know I want this done right.

I'd expect to pay about $1 sf to have a crew place and finish with a $1500 minimum.

5) Think I'm getting in over my head? It'll be a simple workshop - vehicles, woodworking, welding, etc... No major loads or activities

I'd sub it out. Do the prep yourself but you only get one chance at a flat smooth floor.

Give my Guide to Floor Slabs in the link below a read for some additional thoughts. Good luck whatever you decide to do and congratulations on your project

As a very late followup, here's what we did

https://imgur.com/a/iHD73X1

(pics in link have descriptions) but in a nutshell; sons and I did the rebar over a weekend, floor wasn't perfectly flat so we ended up with an average of 5", but I paid for all materials & subs separately so I had the risk. Ended up manually troweling in the colors, very happy with the look. It has very slight ridges here & there, maybe 1/16" max, no issues rolling things around. Cut joints myself with a very old skilsaw, no visible cracks 9 months later.

Euclid super diamond clear went on easy, love the gloss but stinks bad. Am noticing oil drips seep in, but the color makes it less noticeable. Will need to reseal every few years I think, 5 gal did inital & second coats, so should get 3 out of the next bucket.

Very happy with the floor, mostly because it's not dirt anymore.

 

[78SC4X4]

I'm sure location has a big impact, but I paid $1.75per sq for a power troweled finish after I did all the prep work. I considered doing it myself in multiple pours. But I would have needed to rent the line pump multiple times and cash in a lot of chips with friends. Even with a couple of neighbors, you'll be hustling to place the concrete, screed, rake, etc.

And then I watched the crew and was so glad I didn't try to do it. It would be hard to match a good crew that knows what they are doing.