Help With Initial Water Volume.

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As the title suggests I'm after a little help with the calculations to work out how much water volume to start your mash with.I'm about to do a BIAB LC bright ale.I'm looking to knock out about 22LAnd I know the efficiency of the brewery has a lot to do with this but a cant find any info on how to calculate the brew house efficiency or work out trub loss.I have ordered a copy of how to brew so I'm sure I'll learn it all in there but I want to brew tomorrow. Any help would be great.Cheers
 
BIAB calcs sorta of work in reverse, so you go up with volumes instead of down.

So,

You want 22L at the end into a cube or what ever. it goes:

22L + 15% boil off - 15% is an over estimate but will get you started.

So, 22L+ 15% = 25.3L

Then you have grain absorption, at about 1L per Kg.

So if your grain bill is 5kg, its 25.3L + 5L grain loss = 30.3L

THEN there is the kettle loss, being BIAB, one vessel - AKA Trub, pick up tube position, not squeezed from bag etc loss...

I would start with 2L, if you have not tested it..

SO, start volume would be around 32-33L for a BIAB brew, with 5kg of grain.

Probably what you know already but thought I would post it.

CHeers
 
BIAB calcs sorta of work in reverse, so you go up with volumes instead of down.

So,

You want 22L at the end into a cube or what ever. it goes:

22L + 15% boil off - 15% is an over estimate but will get you started.

So, 22L+ 15% = 25.3L

Then you have grain absorption, at about 1L per Kg.

So if your grain bill is 5kg, its 25.3L + 5L grain loss = 30.3L

THEN there is the kettle loss, being BIAB, one vessel - AKA Trub, pick up tube position, not squeezed from bag etc loss...

I would start with 2L, if you have not tested it..

SO, start volume would be around 32-33L for a BIAB brew, with 5kg of grain.

Probably what you know already but thought I would post it.

CHeers

No that's perfect explaination thanks mate
 
As the title suggests I'm after a little help with the calculations to work out how much water volume to start your mash with.I'm about to do a BIAB LC bright ale.I'm looking to knock out about 22LAnd I know the efficiency of the brewery has a lot to do with this but a cant find any info on how to calculate the brew house efficiency or work out trub loss.I have ordered a copy of how to brew so I'm sure I'll learn it all in there but I want to brew tomorrow. Any help would be great.Cheers

Download BrewMate, it's free & is perfect for BIAB.
Boil off will depend on a few things like what is your boiling vessel, how hard you boil & for how long you boil.
Losses to trub can only be worked out once you complete your first brew.
Measure your final volume into your cube (if no chill) + your trub loss & there is your efficiency if you use BrewMate.
I BIAB in a 40lt urn & my boil off is 15%, trub loss is 2.5L & that's using a hop bag. Without the hop bag if you toss the hops in loose, you may get a bit more loss.
Cocko's example should get you close if not using brewing software.
 
Try downloading brewmate. It's free, and if you like it you can make a donation to the author.

First enter your grain bill. There's a button on the right hand side of the screen labled 'brew day' or similar. If you enter a few variables such as desired end volume and boil off rate (assume 10 - 15% per hour), it'll help you work out your starting volume. It will also work out brew house efficiency if you enter you og and volume in to fermenter.

Edit: what crusty said.... I don't type fast enough!
 
E Z.

The figures are a starting point, then you work out your own rig, boil off and bag squeezing for grain loss, trub loss etc..

About 5 brews in, you will have your volume with in a ml!

But its the basic math.

Happy brewing!

Cheers
 
I'd recommend using L/hr for boil off rate, rather than % - once you're under way. Percentage doesn't really work when changing volumes within the one vessel. But using the 15% evap rate, as Cocko suggested, will help you plan for your first brew until you can actually calculate how many L's per hr you're losing at a given boil rate.

Record as many figures and info from your brews as you can. That way you'll be better equipped to work out what causes problems if and when they arise.
 
As all the above, only have one thing to add, in my experience BIAB you will loose close to 4 ltrs if you leave all the shit behind, at least in my keggle anyway, happy brewing!!
 
I have a similar question, I am planning on doing the 23 Liter version of: Montheiths Original Ale Clone
The 23 Liter version is shown in this image link.

I get confused when the original version says "mash in 2L/kg for 10 min", so if the grain bill is approx 5 kg then that means (2x5 = 10), I should use 10 liters if water. Surely thats too little.
Shouldn't I be using something like 32-33L as it mentions above in the 2nd post of this thread?
Any help would be appreciated. Thanks
 
Ding, light just went on. Okay, of course, yes I am doing biab. Thanks a lot
 

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