10 BIAB Batch in 10.5 Gallon kettle?

Is there a way to do a 10 gallon all grain BIAB batch in a 10.5 gallon kettle? I was thinking that i could use 8 gallons of water/18 lbs of grain to start and add water after the boil to top off like you would with an extract batch? Ideas?

18lbs of grain would make a low gravity beer. for 10 gallons you really need a larger pot. even a traditional 3 vessel setup would need larger pot. while you can do a partial boil, the hops utilization would be off.

Sure you can. You might want to consider a couple of things though. With 18lbs of grain after you pull your bag, the grain will have absorbed almost 2 gallons of your starting liquid. I would do a 2nd pot sparge of your grains and top off your brewkettle with this liquid to around 9 gallons to start your your boil. Be watchfull of boilovers! After your 1 hour boil you will still need to add 2-3 gallons of water to your fermenter(s) to make your final volume. ( I preboil 3-4 gallons of water the night before brewday in a large pot on the kitchen stove, cover it, and let it cool overnight for this purpose) Good luck!

I could try 20-22 lbs of grain, but I figured it would be best to start with a lower grain bill and work my way up since I haven't done it before. That is a good idea to try a 2nd pot, I have another 4 gallon pot that I could use for the sparge and I could pre-boil some extra water to make sure it is sanitized. Thanks for the suggestions!

Seems like it would be a huge pain.

I do 5 gallon BIAB in a 5.5 gal pot and I actually have to mash in a 6.5 fermentation bucket.

In your case you'll have to sparge to get good efficiency, which will require another vessel. I desperately need a 10 gal bucket to do my 5gal BIAB.

theres nothing wrong with the initial plan. just account for a slight drop in hop utilization and you're all good. also, keep in mind you'll probably take a hit in efficiency due to the small sparge. you can make up for it by partigyling in your 2nd pot so you don't 'waste' the leftover sugar

So should I plan to increase the amount of hops to compensate? So for example if a recipe calls for 2 oz of hops I increase this to 2.5 oz?

you'll only need to compensate for the bittering hops. it shouldn't be that much of an increase either. if you left it the same it'd probably be close enough that you couldn't tell

OK...I'll take a stab at this. Heat up 10.5 gallons to say 200 degrees in your pot. Pour off around 3 gallons into a five gallon bucket. Temper the strike water in the bucket and pot to strike temperature w/ cold water. Split the grain in bags and mash in the pot and the 5 gallon bucket. Combine runnings to fill the pot to the max w enough runnings to keep topping it off during the boil.