I am currently all grain brewing on a 15 gallon brew system and have been brewing 10 gallons in my 15 gallon pot to help avoid boil over. Is it possible to scale my brew up to 15 gallons worth of malts an hops but only use my 10 gallons of water bill and end up with a somewhat high gravity, concentrated wort and then add water prior to fermenting to get my 15 gallons? Kind of like what is done with many extracts. If so, is there a technical term for this I can research? I think these calculations can be done in Beersmith, I am just curious if it is a common practice and recommended.
I would do this when brewing 10 gal batches in my old kettle that was a bit too small for comfort. Keep the amount of dilution as low as possible. Beyond the above issue from major, you also will see reduced hop utilization in the more concentrated wort.
I do this in the summer to help in cooling the beer down to fermentation temps; I can’t tell the difference between brews with all the water added in up front or a thicker mash to start and cold make-up water at the end.
Just make sure that the chlorine has been removed from any top up water.
Lots of newbies don’t realize that it causes dreaded phenolic off flavors.
(Not implying that you would do this, just adding it so those reading the post later and trying it won’t do it either).