How do you guys calculate for trub loss?
 

Just curious, is it just trial and error knowing your going to lose like 1/4th to 1/2 gallon due to trub, or is there some other way to know based on the AG Ingredients/recipe/yeast?

Wondering if i should just start entering in 5.5g for my final volume in Beersmith so i use the right amount of water...

Just trial and error for me.

This is what I do - i.e. I set my 10g batches to 11.5 in Beersmith rather than trying to plug in the 1.5 gal kettle/trub losses (which I have determined by trial and error). I find it's much easier to hit my numbers this way. There was a useful PDF I found in the Beersmith forums that detailed the different ways to set this up, I'll post if I can find it again.

Next time you rack make a mark on your primary. When you clean it then add water up to the mark and pour it back into a graduated vessel and there you go, or, conversely use a graduated vessel to add the water:)

Thread I was talking about is here. PDF file is in 3rd post down. I guess this is the "Est. Mash Efficiency" method rather than "Total Efficiency" method.

If you want to save yourself a bunch of headaches, do NOT use the trub/chiller loss field. Set it to 0, then increase your batch size (use the 'scale recipe' tool with the 'keep OG, SRM, IBU the same' box checked), like mentioned above, to account for post-boil losses.

The root of the problem is that BeerSmith uses 'to the fermenter' for brewhouse efficiency, instead of the more common (and useful) 'in the kettle' BH eff.

If you use the trub loss field for losses, you would have to adjust your 'to the fermenter' BHE to account for it. There isn't a correct formula for this, but it can be approximated. Same goes for if you ever mod your equipment, switch from leaf to pellet, use a high trub grainbill, etc.

It is best to not use the trub loss field at all, and notate in your recipes how much of the batch size was for losses. Some even say to set the lauter dead space to 0, since making MLT changes cause the same issues with BeerSmith.

This is a 100% trial and error variable. It also depends on the style. eg a dry hopped IPA is going to soak up some extra liquid.

With the yeast strains I use, and my processes, I factor on leaving 3 quarts of volume behind in the fermenter for each batch. This means, I typically put 6-3/4 to 7 gallons into primary so that I get a solid 6 gallons out (into two 3 gallon kegs). I don't mind leaving a bit more behind, if it comes down to it. I also have how much will be left behind in the boil keggle, plate chiller, etc. factored into my post-boil volume.

Once you calibrate your system, you won't need to worry about it moving forward. I do have these items entered into BeerSmith, so it's easy to hit my goals.

Generally just make 5.5 gallon batches instead of 5.

Except for it being a lot harder to adapt to changes regarding losses if you enter those trub and lauter losses into the BeerSmith fields. It is much easier to simply increase/decrease the batch size by the known amount of an equipment change, or the amount of hop absorption when switching from pellet to leaf, or a hoppy brew. It is more work (you need to do a new efficiency calc/tune), and bit of a crap shoot the first time, if you enter them into BeerSmith.