You’re mashing with 4.5gal or 18 qts so that’s about 1.6 qts/lb for your 11.35 lbs grain so you’re close to your 1.5 estimate. Working backwards from your 5 gal bottling volume, add 0.5 bottling loss = 5.5 gal batch size + 0.25 trub loss + 0.24 cooling shrinkage = ~5.98 post boil volume needed + 1.13 gal boil off = 7.11 pre boil volume needed. My assumption on cooling loss and shrinkage is that is the expected decrease in volume of your liquid from boiling to fully cooled temperature (thermal contraction as it cools)
Thanks for that…how did you come up with the 1.6 figure? The mash thickness is actually set to 1.497 in Beersmith in this case. Not a big deal, just curious.
I took total mash water which is listed as 4.5 gal = 18 quarts divided by total grain weight of 11.35 lbs = 1.59 qts of water per pound of grain. It looks like if you subtract out the tun dead space of .25 you get 4.25 mash volume = 17 quarts divided by 11.35 pounds of grain = 1.497 number. Never noticed that before. Not sure which is the “right” way to handle the dead space but not a big difference between the two. I learned something there. thanks!