Is a 10 gallon big enough? I will be doing BIAB for 5 gallon AG batches but some recipes call for 12+lb grain bill.
Yup. I do 5 gl BIAB, and I use a corando kettle 10 gl stainless. Works great.
You can mash up to 15 or even 16 pounds in even just a 5-gallon kettle. However your efficiency would suck (like, 40% or something) as you’d have to mash thick and then add the rest of the water to the kettle after.
But in a 10-gallon kettle, you can go huge and it should be just fine, without as much impact on efficiency, depending on how hard you crush, whether you have capability to rinse the grain bag, etc.
With big grain bills, more than 10 pounds, I divide the grist into 2 or even 3 bags and clip all to the top of a 10 gallon brew kettle. Great tip I got right here, that will save your back. You’ll need two(or even 3) sturdy strainers and a smaller pot(s) to sparge.
Cool. Just making sure. Didn’t want to go up to the 15.
thanks guys.
Curious about your process do you just dunk the full bags like tea bags ? I usually stir my grains ino the bag
One of those situations where a picture would be worth a thousand words. Each bag shares either half or a third of the opening of the BK. I can and do stir the grains with the bags secured to the rim. When I do the saccharine rest I carefully unclip and place the lid over the BK before the sleeping bag and blanket avalanche occurs. Works great and I love it when at 60 minutes the thermapen reads 151 
I started with 10, but ended up with 15 for simplicity
I went with a 15 gallon
http://amzn.to/1SajjnH
almost by accident because I didn’t relize how big it was, and originally wanted to do 3 gallon batches. While I can’t do 3 gallon as easily I’m glad I have the larger size. Makes it very easy to stir the mash and not get doughballs or clumps. I also have room to put a 5 gallon paint strainer bag as my hop bag without it getting in the way. I have a couple videos demonstrating it.
With big grain bills, more than 10 pounds, I divide the grist into 2 or even 3 bags and clip all to the top of a 10 gallon brew kettle. Great tip I got right here, that will save your back. You’ll need two(or even 3) sturdy strainers and a smaller pot(s) to sparge.
So the 2 bag system is only for the lifting aspect, no other benefit? No increase in conversion or anything like that?
Just for ease of handling. Some guys use hoists. I still brew indoors. SWMBOmight balk at a hoist pulley system in the kitchen 
Seriously when I brewed the Pliny kit from our host as a newb all grain attempt I had some anxious moments lifting that ginormous wet bag with the poor strainer buckling under the weight.
Sparging onto a second or third bag sitting on separate pots and then adding the collected “runnings” to the BK is easy.
I have the 10 gallon Tall Boy and I typically do 5.5 gallon BIAB batches in it. Biggest grain bill I’ve had so far was a bit over 14 lbs. It all fit with maybe an inch of kettle to spare. On the plus side, all that volume in the kettle means you don’t lose much heat to deadspace during the mash rest.
With a 10 gallon BK that sounds like a lot of wort volume! I assume you are doing a no sparge?
I agree, the temperatures hold well with that kettle and batch size.
With a 10 gallon BK that sounds like a lot of wort volume! I assume you are doing a no sparge?
I agree, the temperatures hold well with that kettle and batch size.[/quote]
Yup, no sparge, unless I need to to reach my pre-boil volume, which has only happened a couple of times. I’ve got the water volume calculations from BeerSmith dialed in pretty good now.
