Pre-boil/Post boil OG question

[AKnewbrews]

I am pretty sure I know the answer to this, but I am just curious if anything OTHER than water boil off changes the gravity of the wort during the boil period.

I brewed an IPA the other day, target OG was 1.067 @75% eff. I got exactly 5 gal 1.070 wort after mashing/sparging. My target batch size is 5 gal, but I knew that after I boiled, my OG would increase due to water boil-off. So I added water about half way through the boil to increase the volume to 5 gal by the time th boil was complete, which is the volume I got into the fermentor.

So, my question is: Did I still have a 1.070 OG beer of 5 gal after boil because the volume is still 5 gallons?

This all stems from the fact that I forgot to take the OG reading after the boil, so I really do not know if it was 1.070 or not.

 

[Calder]

Only water boils off. The sugars remain.

 

[AKnewbrews]

Cool, so luckily I happened to get exactly 5 gal wort after sparge and I at least hit my target OG. I ran out of hot liquor. Next time I will have to use a little more sparge water to get a better pre-boil volume so I don't have to add later on. I had 4 gal in mash and 3 gal sparge water. 2+ gallons went to grain absorption and evaporation with only a pint or two left under false bottom after sparge.