Getting 10 gals from a 7 gal kettle

[chainlife]

Has anyone tried watering down like 6 gals of really high gravity wort into 10 gals of a light beer? I have a party coming up, I need 10 gals, my capacity is 5 gals, but would like to try to knock it out in one brew. Is this a terrible idea?

 

[broadbill]

Has anyone tried watering down like 6 gals of really high gravity wort into 10 gals of a light beer? I have a party coming up, I need 10 gals, my capacity is 5 gals, but would like to try to knock it out in one brew. Is this a terrible idea?

Nope, this is how most beginners do it...boil volume you can, top off with water.

The concentrated wort will decrease hop utilization, so you need to bump up your additions to compensate. There may also be increased carmelization with boiling a more concentrated wort.

The larger issue is that you'll be doing a new process on a hard deadline (the party). There is a chance that the beer may not be quite right because you don't have your process dialed in (over/under hopped, too diluted, etc.). You may not have time to redo and it might be better to brew with your known process and buy 2 cases of beer than to have 10 gallons for bad/mediocre beer.

Depends on how important this party is.