Regarding Base Size Class

With the current base i am in, it is size class 7, currently 7.07, which is over 7 but still classed as size class 7. Does this mean i am i allowed to continue building until 7.99? or should i reduce it to be exactly 7?

It rounds up at some point, I’m not exactly sure when.

I would go with reducing the size, personally. If it takes damage (missing blocks) size class could jump up due to more exposed block surfaces. Something as insignificant as a random drone strike could cause damage and cause the size to spike over the allowed limit.

class 7 can go up to 7.49

As TwitchyJ allready wrote, stay save with 7, you could go up to 7.49, but if yiu get a slght Damage, it could jump to 7.51, what rounds up to 8 and this will be deletet.
Hint: Windows and Lights rise the Level the most, so instad of 6 Lights in one room, set the light range higher and save Lights, Level and Energy.