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BIAB fermenting

I’ve got a NB BIAB 3 gallon recipe, Belgian IPA, in the fermenter. (My first BIAB brew).
The instructions state it can be bottled after 1 week in the primary but the airlock continues to bubble and the beer continues to clear so I’ve left it for two weeks.
Is there any problem with leaving it another week? I’ve always gone three weeks in primary then bottled and so far my novice beers have been very good.
Is three weeks too long for BIAB?
I realize I could measure gravity and wait a few days and repeat but by then it will be almost three weeks anyway.

BIAB, extract, cooler system, rig, etc… doesn’t matter how you mashed. How you mashed and how long you ferment aren’t related. Ferment as you normally would. 3 weeks will be fine. Take gravity readings and let that tell you when to bottle, not the calendar or how you mashed.

+1 Dobe is right, your hydrometer is the brewers best friend. Calender brewing will get you in trouble. I’ve noticed reading some recipes out there say, 2 wks for this, 2wks for that, 2wks for this.
I don’t buy that at all, as beer will work on it’s own schedule. It may work out that way but it’s not a given. I find having patience has saved me many times, but that’s just me. To me aged beer always tastes better.


Tear up the instructions that come with any kit!

Read “How to Brew” by John Palmer. (free, somewhat out-dated version free at

Follow this forum.

Rant concerning kit instructions withheld to avoid revealing my excessive collection of offensive language!

+1 to this. You could even extrapolate this no-chill, immersion chill, etc. Once the wort is in the fermentor it doesn’t matter how it got there, how it was chilled, how it was mashed, boiled, or hopped; ie- fermentation will take place as a factor of available sugars, environment, and yeast health. Gravity readings are your friend.

I just bottled the same brew. Do to life getting in the way, I let mine set for 4 weeks. This was my first BIAB, and the first that was crystal clear when I bottled. My FG was 1.012. Now the wait to give it a taste. Cheers!

+1 what Dobe said. Use the hydrometer. I’ve made 10 gallon batches for a while, and sometimes (actually right now) I split the wort between two 5-gallon buckets if my big fermenter is working. I’ll pitch the same amount of the same variety of yeast into each bucket, and had it work differently in buckets side-by-side. Not much different, but slightly. If there was a big difference, I would think there was a problem somewhere, and I would start checking. But I’ve had differences of about 2-3 days in the ending of each batch, side-by-side. So, use the hydrometer. (Also +1 on reading Palmer’s book, read it online for free, then order it and keep it close by. There are several other books to add to your brewing library over the next few years too).

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