What's your maximum capacity BIAB brews?

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Garthmuss

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I'm in the middle of deciding between a 15 gallon or a 20 gallon custom Spike kettle and a custom Utah BioD basket, and it got me thinking about the parameters of my brewing.

The question:
What are your kettle sizes and what's been your biggest batch you've made in regards to either gravity or volume or both? How does it work for you and what hurdles do you jump over to get the biggest batch possible out of your system?

I generally brew 19L (5 gallon) batches into my kegs, probably 9 times out of ten. But I take great joy in brewing mixed fermentation sour beers or other funky aged beers and aging them in bottles. Obviously it behooves me to brew as large a batch as possible so I can drink them semi regularly as they age and still have bottles of them in a couple/few years. Generally I aim for 1.060 to 1.080 gravity on these as it seems they age better when they get over 7% abv, and sometimes I shoot for the stars and brew even higher OG batches. There's not really any incentive to get to an even 38L (10 gallon) batches because everything I keg I don't mind just having one keg, and anything else I just bottle.

So I every time I end up brewing a big batch of wort to sour and bottle condition, I find myself wondering just how much volume I can get into my fermenter, to maybe end up with one more bottle in the closet. I can get a strike volume of 35L and 7.5 kilo of grain in my system, and then finish around 25L at 1.070. I'm mainly limited by my current brew basket which is somewhat smaller than my pot I have considered purchasing a bag to get around that issue. I've never mashed thicker and sparged, which I've considered just doing a cold sparge and bringing up to pre boil volume.

I imagine with the spike 15 gallons and custom basket setup, I'll be able to strike 40-45L of water and add around 12 kilo of grain to it. Which may get me to around 30-35L into fermenter at roughly 1.060 OG? Just estimates.
 
I do high gravity brewing with 4 - 15 gal vessels. 1 mash tun, 1 HLT and 2 BK's, with 2 mashes. 1st mash (BIAB) done in BK #1 then then the bag is pulled ,drained and squeezed enough to transfer to BK #2 without dripping too much. The HLT liquor is put into BK #2(dunk sparge),then pumped up to the mash tun(with a bag so I can use the same mill setting) and I mash the second set of grains. I refill the HLT for a sparge.
When the second mash is done it gets drained into BK #1 and the second sparge gets drained into BK #2. So I have 12-13 gal of super high gravity wort and 7-8 gal of second runnings are between 1.040 - 1.050.

You need to make a decision now, 10 gal of first runnings and a small beer or parti gyle and mix them.

I've done both and this is what I get...........27 LB x 2 mashes = 15 gal( 3 kegs) of 1.100. The real beauty of the procedure is that I only need to boil 60 min,but I'm boiling 2 kettles.
I do this so I can fill 15 gal barrels in one brew day with a 12-14% beer.

The most grains I can fit is 34 lbs, and with that I get 1.134 ~11 gal and a 1.060 small beer LOL.
 
5gal kettle, 3.7ish gal into fermenter, 1.095

By maxing out the mash volume [and thickness], 4.7ish temp corrected gallons [@~1qt/lb], then a room temp dunk sparge in a 5gal bucket. With the 2nd runnings [1st & 2nd runnings being equal volumes] added to the kettle that maxes out pre-boil volume at about 4.5ish temp corrected gallons. An ounce or so of first wort hops and a close eye keeps boilovers in check. A gentle boil keeps my boiloff down and my post-boil volume up.

I seriously push the limit, but don't believe the 3x batch volume rule. There are plenty of [not very difficult] ways to get more out of a smaller kettle.
 
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If you only plan to brew 5 gallon batches, then a 15 gallon kettle should be plenty.

My setup is a 10 gallon kettle targeting 73% overall efficiency. I generally target 5.5 gallons into the fermenter and plan for 1 gallon of boil off for a 60 minute boil. I find I can get to about a 1.070 beer following a full volume mash setup (bigger for beers that have sugar/additions into the boil). To push above that I just need to set aside some water for a sparge, or reduce my batch size.

My recent IPA was 13.5 lbs of grain and I hit 1.070 (that one just had a 30 minute boil). I just brewed a Tripel that hit 1.075, but that one had 1.5 lbs of sugar in the boil.

My biggest batch was 5.5 gallons into the fermenter for a 1.118 Imperial Stout. Looking at my notes, I just needed to sparge with 1.6 gallons of water. That batch was 23.5 lbs of grain. I did end up with about a full gallon of loss to trub settling in the fermenter. Adding in the sparge, boosted my efficiency and OG higher than I had planned.

Based on a prior Imperial Stout, I can produce about 4 gallons of wort in the 1.100 to 1.110 range following a full volume mash process.
 
I'm in the middle of deciding between a 15 gallon or a 20 gallon custom Spike kettle and a custom Utah BioD basket, and it got me thinking about the parameters of my brewing.

The question:
What are your kettle sizes and what's been your biggest batch you've made in regards to either gravity or volume or both? How does it work for you and what hurdles do you jump over to get the biggest batch possible out of your system?

I generally brew 19L (5 gallon) batches into my kegs, probably 9 times out of ten. But I take great joy in brewing mixed fermentation sour beers or other funky aged beers and aging them in bottles. Obviously it behooves me to brew as large a batch as possible so I can drink them semi regularly as they age and still have bottles of them in a couple/few years. Generally I aim for 1.060 to 1.080 gravity on these as it seems they age better when they get over 7% abv, and sometimes I shoot for the stars and brew even higher OG batches. There's not really any incentive to get to an even 38L (10 gallon) batches because everything I keg I don't mind just having one keg, and anything else I just bottle.

So I every time I end up brewing a big batch of wort to sour and bottle condition, I find myself wondering just how much volume I can get into my fermenter, to maybe end up with one more bottle in the closet. I can get a strike volume of 35L and 7.5 kilo of grain in my system, and then finish around 25L at 1.070. I'm mainly limited by my current brew basket which is somewhat smaller than my pot I have considered purchasing a bag to get around that issue. I've never mashed thicker and sparged, which I've considered just doing a cold sparge and bringing up to pre boil volume.

I imagine with the spike 15 gallons and custom basket setup, I'll be able to strike 40-45L of water and add around 12 kilo of grain to it. Which may get me to around 30-35L into fermenter at roughly 1.060 OG? Just estimates.

I've got a 15 gallon kettle. Most beer I brew is 1.030 to 1.060. I usually use 9-10 gallons in the mash and then make up the rest of the volume with sparge.
I recently started playing around with topping up at the end of the boil with RO water to get a little more volume out.
 
I've got a 15 gallon kettle. Most beer I brew is 1.030 to 1.060. I usually use 9-10 gallons in the mash and then make up the rest of the volume with sparge.
I recently started playing around with topping up at the end of the boil with RO water to get a little more volume out.

Interesting! you use a brew bag not a basket?
You brew full 10 gallon batches with this method?
I've been meaning to try a larger grain bill and then sparging. Next time I brew big I will
 
Interesting! you use a brew bag not a basket?
You brew full 10 gallon batches with this method?
I've been meaning to try a larger grain bill and then sparging. Next time I brew big I will

I use a bag with pulleys. I raise it out, drain it a bit, then shift it over to another pot that I have filled with room temp sparge water. Drop it in there, undo the bag and stir it around for a couple minutes. Then raise it again and drain it some more. Put the grain bag in a bucket to take to feed the chickens. Dump the sparge into the main kettle. Start the boil (can't boil 15 gallons b/c of volume loss to the condenser). I lose about a gallon at the end of the boil to trub (more for very hoppy beer), so I started adding back a bit of water to get 11.5 gallons to the fermenter.
I also just got a trub filter for the bottom of the kettle, which I haven't tried yet but looks to reduce those losses by quite a bit.
 
I use a bag with pulleys. I raise it out, drain it a bit, then shift it over to another pot that I have filled with room temp sparge water. Drop it in there, undo the bag and stir it around for a couple minutes. Then raise it again and drain it some more. Put the grain bag in a bucket to take to feed the chickens. Dump the sparge into the main kettle. Start the boil (can't boil 15 gallons b/c of volume loss to the condenser). I lose about a gallon at the end of the boil to trub (more for very hoppy beer), so I started adding back a bit of water to get 11.5 gallons to the fermenter.
I also just got a trub filter for the bottom of the kettle, which I haven't tried yet but looks to reduce those losses by quite a bit.

Same sparge process here.
 
I’m still waiting on equipment to start back up. I used to easily do 9 - 10 gallons (37L) in a 15 gallon BK. I’d also do a lot of 5 - 8 gallon brews.

Its more a logistical hassle when you get to bigger volumes.
- How are you going to lift more than 30lbs (14kg) of soggy grains after mashing?
- Do you need to lift your BK *before* transferring to a fermenter? With equipment, it’s probably more than a 90lbs (41kg) lift.
- How are you going to ferment 10 gallons (37L)? Are you going to split between two buckets?
- Do you have a 2L or 3L flask for making a big enough starter?

There are a lot of fun things you can do with a system capable of brewing & fermenting 10 gallons at a time. I used to make 10 gallons, split it into two buckets and ferment with different yeasts. I also used to do a double 5 gallon brew day and pitch the same yeast into two different styles of wort.
 
Generally speaking kettle should be 3x batch size to handle any high gravity beer you throw at it. If you are 100% sure you will never do a high gravity beer you can get away with less.

for a traditional 5 gal recipes, a 15 gal kettle will handle any high OG beer you attempt.

Any lesser beer you will have lots of extra room.
 
I'm mainly limited by my current brew basket which is somewhat smaller than my pot I have considered purchasing a bag to get around that issue. I've never mashed thicker and sparged, which I've considered just doing a cold sparge and bringing up to pre boil volume.

A brew[ing] bag isn't very expensive.* Maybe give one a try along with a room temp sparge and you'll find all your volume issues disappear with plenty of cash still in your pocket.

[*One high-quality option being more so than another.]
 
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A brew[ing] bag isn't very expensive.* Maybe give one a try along with a room temp sparge and you'll find all your volume issues disappear with plenty of cash still in your pocket.

[*One high-quality option being more so than another.]
A brew bag will definitely help there and I've thought about it, but I brew outside and can't set up a pully on a ceiling. I am able to hoist a brew basket up about 12 inches and (with the right hardware) latch it to the edge of the pot to let it drain. Plus, I like shiny new equipment and I've been saving up for a while for it :thumbsup:
 
A brew bag will definitely help there and I've thought about it, but I brew outside and can't set up a pully on a ceiling. I am able to hoist a brew basket up about 12 inches and (with the right hardware) latch it to the edge of the pot to let it drain. Plus, I like shiny new equipment and I've been saving up for a while for it :thumbsup:

Get spending then!
 
If you plan on brewing 10 gallon batches with any level of consistency definitely get a 20 gallon kettle. Like others have said a 15 gallon kettle is good for any 5 gallon batch. I made the mistake of getting a 15 gallon kettle and now regret it. I brewed a 10 gallon batch yesterday, held back a free gallons for sparging (dumping over the hanging bag) and I got a lower OG than intended. The water mostly road the outside of the bad and went into the kettle clear. The last batch I tried to do full volume mash and ended up getting wort everywhere.

If you do decide to go with a 15 gallon kettle, please buy mine so I can upgrade to a 20 😁
 
sparging (dumping over the hanging bag) and I got a lower OG than intended. The water mostly road the outside of the bad and went into the kettle clear. The last batch I tried to do full volume mash and ended up getting wort everywhere.

This doesn't read to me like an issue of a too small pot. Besides, OP declared no interest in 10gal batches.
 
How would what I describe not be an issue of too small of a pot? Total volume exceeded what was possible in my 15 gallon kettle and for that reason I need to sparge.

I should have read the post more carefully to determine he wasn’t interested in a 10 gallon batch but the content initially lead me to believe otherwise.
 
I have a 15 gallon kettle (eBIAB) and have done 1.068 beers to 12 gallons. Probably could do bigger beers if I wanted to. However, that's with a dunk sparge in a smaller kettle.
I rarely do this but when I do, I use a strainer to remove some grain into 2 smaller mesh bags and dunk those in the small kettle. Doing this I still get 74% efficiency or better.
 
How would what I describe not be an issue of too small of a pot? Total volume exceeded what was possible in my 15 gallon kettle and for that reason I need to sparge.

Too small for a full-volume mash, sure. Pouring a sparge over a hanging bag doesn't work very well, as you found. A more effective sparge, like a well-mixed dunk with 40-50% of the pre-boil volume, would have increased your efficiency.

So yeah. A bigger pot or an effective sparge.
 
Yes if OP wants to sparge, a lot of possibilities with a 15 gallon kettle. I find moving a bag of dripping grain around makes my brew days less enjoyable and prefer to do a simple full volume mash. OP will need to make his own decision. But as established, if he is planning to do less than 10 gallons this is likely not an issue.

I purchased a 15 gallon kettle when I started brewing thinking 5 gallon batches is all that I wanted to brew. Within a year I learned that brew days are long and making 10 gallon batches was the way for me. - this may not be relevant
 
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With my 15G kettle, my largest grist so far was 22.5# and that is with a full volume mash, no sparge.
Pretty close to my max effort...25# grain in a 15 gal kettle, full volume mash...I was about 1" from the top
 
I have a 16 gallon kettle that is basically the same diameter as the spike 15 and only make 5.7g into the fermenter. My false bottom is about 3.25" from the bottom and some full volume mashes are pretty dry because of the amount of space below the false bottom. I'm considering for my next upgrade to get one of the Brew Hardware false bottoms flip it over so the support ring faces up and drill for bolt supports so I could lower it to 2 5/8". I really want a 14.5" diameter 15-16 gallon kettle.

In that 20 gallon kettle you will have 3-4 gallons below your false bottom. I think you would sacrifice utility on 90% of your brews just to allow a full volume/near full volume mash on a 10 gallon batch. If I was you, and none of us are :) , I would go with the 15gallon and sparge the hanging grains and add top off water after mash to get to the larger batches you brew 10% of the time.
 
I brew 5.4 gallon batches.
Here's about the biggest I can go - 17 pound grain bill in my 10 gallon kettle... :oops: :)

BIAB1Mash_1.jpg
 
22.6 lbs in an SSBrewtech BME kettle (12 gallons). Had to use a smaller kettle to batch sparge with 2.5 gallons of the 10 gallons of strike water. Not counting the 1lb of dextrose. Did @Dgallo 's Triple NEIPA recipe. Turned out amazing with 10.2% abv.
 
22.6 lbs in an SSBrewtech BME kettle (12 gallons). Had to use a smaller kettle to batch sparge with 2.5 gallons of the 10 gallons of strike water. Not counting the 1lb of dextrose. Did @Dgallo 's Triple NEIPA recipe. Turned out amazing with 10.2% abv.
I hope it works out well for you. The Riwaka, Citra, Nelson combo is probably in my top 3 Favorite combos
 
I regularly mash 24 pounds of grain in 12 gallons of strike water in a 15.5 gallons BIAB tun/kettle for 1.060 gravity beers. That is enough wort to ferment and fill two corny kegs with beer.

For higher gravity beer I target enough wort to fill a single corny keg.
 
I guess I'm actually a MIAB guy. But I regularly do 16# in my 10g Igloo cooler for 5 .5 gallon batches. I like high gravity beer. I suppose I could do a couple pounds more with my no sparge but it hasn't happened yet.
 
I do a modified BIAB on my stove top with a 9 gal "tallboy" BK with a turkey basket holding my bag. After mash and mash out, I hoist the basket/bag and pour sparge water through the raised grains into the BK. With this setup I can do up to 16.5 lbs of grain and reach about 1.085 for a 5 gal batch with no sugar in the boil. I've gone as high as 1.118 for a 4 gal Belgian with some sugar in the boil.
 
I use a 15.5 G keggle for 10 gallon batches using a wilser BIAB and a hoist. My last batch probably had as much grain, 32 lbs, as the most I've ever used as mash water was spilling out of the top of the keggle. I had actually planned to use 2 more lbs of grain but there was no way they were going into the keggle without a corresponding amount of overspill.

The mash consistency was very thick but I mashed for 2 hours, sparged between 1 and 2 gallons with room temp water after the mash, and ended up with 76% mash efficiency.
 
I have 15 gallon Spike Kettles and I do full volume/no sparge BIAB exclusively. My largest grain bill I typically make is around 14.5 lbs but I could go more with ease. Plenty 'o room.
 
I will generally run 8 gallons of water with anywhere from 10 to 14 pounds of grain in a 44 liter pot. Mashing goes great, and haven't had a boil-over yet.
 
I do 10 gallon batches in a 20 gal pot. Biab(asket). Holds any grain bill I want and boilovers are only a problem if I leave the hellfire wide open. Don't do that. I would suggest that the 20 is a good choice for 10 gal batches and the 15 is fine for any 5 gal batch you can think up.
 
I don't know what my maximum capacity is but I have done several batches where the wort is only half an inch from the top of the pot when I finish sparging. It takes some whisk action to keep it from boiling over.
 

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