Hi all,
I am replacing all the old columns in my basement (there should be 5; 2 were removed at some point over the decades for no good reason, 1 is a temporary screw jack, and 2 are rusted out at the bottom) with new lalley columns and pouring new spread footings while I’m at it (2′ x 2′ x 1′ deep, reinforced with rebar).
Each hole will need about 8 – 80lbs bags.
I will be working in phases, with the 2 missing columns first, then the others 1 at a time. If it were all 5 at once I would rent an electric mixer for a day. However doing it in a few steps I would rather not have to rent a mixer 4 times.
What would you all recommend for best way to mix the necessary bags for each footing? I don’t want a cold joint obviously, but could I mix 2 bags at a time in a large tub fast enough to do it in 4 batches per footing? Or should I just suck up the $70/day and rent a mixer each time?
Thanks for your input,
Drew
Replies
Mixing 8 bags at a time shouldn't take long at all, certainly not long enough to create a cold joint.
I bet if you visited u tube you'd find some clever ways to do it. Lacking a mixer a wheelbarrow and a mortar hoe are reasonably quick.
Thanks very much -- I ended up doing it by hand in a big mixing tub, 2 bags at a time. Went quickly enough
The hardest part of the project will be hauling the concrete to basement, not the mixing. I would place eight bags by each footing for easy access. If you have clay or very compacted dirt that isn’t loose you can mix the concrete in the footing. Should be able to do two bags at a time. Run a hose into the basement for water, so you do not need to haul water buckets. If you have loose dirt can line plastic sheeting in footing over the dirt to keep the mix clean. All you need is a hoe for mixing. If you do not have a lot of experience mixing to right consistency measure out the recommended amount of water into a bucket and make a mark in the bucket to indicate fill line for progressive footings. Wear a mask if you can find one, concrete dust is cancerous to inhale. If no mask wrap a t shirt around your face. If you have forced air for heating and cooling would be a good idea to shut that off, so you aren’t pulling concrete dust all over your home.
Mixing concrete by hand isn’t too bad but watch a few YouTube videos. There are definitely tricks that make it way easier. If you’re physically not up to it, the Harbor Freight cement mixer is under $200 with the right coupon and I bet you could get $100 for it on Craigslist or Facebook Marketplace when you’re done with your project. It’s not a bad tool. I’ve had one for 3 years and we use it all the time for pier footings and the like. It will mix two 80lb bags at a time.
Thanks for your advice -- after mixing it 2 bags at a time and pouring yesterday, you're definitely right the hardest part was lugging all the bags into the basement. Luckily I have a few masks laying around (I am a cabinetmaker so I had the end of a box in the shop that are at the house full time now) and it's steam radiators only so was able to keep my lungs and the rest of the house clear.
5-gallon buckets are your friend. Do a single bucket as a test first with say, 4 inches of water and a bag of concrete. Mix with a 1/2" drill and a paddle mixer. Adjust the water and concrete until you get a good mixture. At that point run the water into all the buckets you have and dump in the mud and go to mixing. If you have the mix right it will mix right up very quickly. I've done 40 or 50 bucket pours in 30 minutes or so. We usually use at least 10 buckets at a time.
I may try this on the next 3 footings. I got through the bags alright for the first 2 yesterday but my back and arms were hurting today and it made work in the shop a bit sore. I have a mixing paddle from some tile work a few years back so that may be the way to go. Thanks very much for your advice.