How to do Brew In A Bag Brewing (BIAB)

Looking to up your home brewing game eh?


Then I have good news for you my brewing friend, you have come to the right place to learn how to get into all grain brewing and especially my favorite BIAB or Brew In A Bag method of all grain brewing…

Brew in a Bag or BIAB is by far the easiest method of All Grain brewing and on top of that it makes damn good beer, as good or better in many cases as the 2 vessel and 3 vessel brewing systems on Brew in a bagthe market…

… but with a lot less expensive start up cost for your equipment… and a lot less time and work required on brew day!

Why everyone does not do brew in a bag brewing beats me!

I first got my start into all grain brewing using the Brew in a Bag (BIAB) techniques I am going to show you on this page.

In fact I still do all of my all grain brewing of my beer using BIAB methods… yes I have definitely upgraded my systems a few times, but the basic premise I use for brewing beer is the exact same as the day I first started brewing all grain beer.

Before we get started here I would like to point out that I am assuming that you have some home brewing experience and have made some beer.

Whether that is kit beer or partial mash of maybe even all grain but with a 2 or 3 vessel system…

… I say this because I am not going to go into the basics of brewing. Meaning I am not going to cover how to ferment, carbonate, or the importance of sanitation, etc…

… This page is going to be focused on the steps involved in BIAB brewing.

So if you are brand spanking new to making beer I recommend you check out some of the other posts and videos on this blog first and get your feet wet with brewing before moving into all grain.

Then come back here and get down and dirty with the BIAB brew!

Ok… so what is this top shelf method of all grain brewing all about?


The basic premise is that you do all of your brew day activities… the hot side of making beer in 1 vessel instead of 2 or 3 vessels.

And you accomplish this with the aid of a mesh bag!


Let’s take a look at the 3 vessel system and use it as an example of the differences with BIAB.  3 vessel brewing system

In the 3 vessel system you have 3 vessels… DUH! Lol

==> Hot Liquor Tank (HLT)

==> Mash Tun (MT)

==> Boil Kettle (BK)

In the Hot Liquor Tank you heat the water up to temperature to be able to be used for the mash and sparging. You then transfer the water to the Mash Tun…

In the Mash Tun… you soak the grains in the hot water in order to get the sweet goodness out of them… the mash tun has what is referred to as a false bottom… so that when you transfer the wort (sugars from the grains mixed with the hot water) over to the boil kettle you leave the used grains behind…

Boil Kettle… And of course the boil kettle is where you boil the wort and add the hops, etc.


Now let’s take a look how it works with Brew in a Bag or BIAB…

As previously indicated with the Brew in a bag system you do all of the above in one vessel or kettle with the help of the bag!

Here is what a brew in a bag brew day looks like.

You start your brew day by filling your kettle up with your water…

… you then bring that water up to the strike temperature (temperature you will dough in at aka add the grains)…

… once the strike temperature has been reached turn the heat off… and put the bag into the kettle… BIAB

… you then slowly add the grains into the bag, stirring as you go to ensure that the grains do not form into clumps.

… once the grains are all in your kettle, you put the cover on and the mash begins.


One of the challenges of BIAB brewing is temperature control… maintaining the correct mash temperature that the recipe calls for…

You can control this by insulating the outside of the kettle… I use to do this by wrapping the kettle in towels or blankets and putting pillows on top of the kettle.

Yes this is a bit ghetto, but an inexpensive method of maintaining the temperature and it works just fine!

Don’t get to worried if the temperature starts dropping over time, it’s ok… just insulate the kettle as best as you can and let it ride, it will be fine!

Once the mash is done… pull the bag out of the kettle and hold it over the kettle letting it drain all of the wort back into the kettle.

There are different ways of doing this… the easiest is to get a strainer that will sit across the top of the kettle and lay the bag of grains in it… letting the liquid drain into kettle.

You can pour some sparge water over the top of the grain bill (bag) in order rinse the rest of the sugars out of the grains and to bring the water level up to the correct pre volume level as per the recipe…

Now simply remove the grain bag… put the kettle back on the heat source and crank it up to Boil baby… and carry on with your recipe


Most of the time I now use the Brewers Edge Mash & Boil as you will see in my videos. brewers edge mash and boil

This is an electric kettle and simplifies the whole process… in fact it is so dang easy it is almost embarrassing! lol

You can check it out here if you want to get one for yourself:

click here for Brewers Edge Mash & Boil

And the bag for the BIAB I recommend you use is the Brew Bag… great quality and has handles that make it great to use.

You can check it out here if you want to get one for yourself:

click here for The Brew Bag

And that is the basics of a BIAB brew day!!

Easy peasy… quick and dirty… a lot less effort time and energy… with the same results… i.e. great tasting beer!

Now I realize this was a high elevated overview of Beer in a Bag…

NOTE: If you want more information on how to brew beer in this method be sure to jump on my newsletter at the bottom of this page.

I am big into BIAB brewing and send out lots of good information on how to do it right!


Big Robb

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