If you can conditioned air from the house is usually the most cost effective way of doing it. You may need to supplement a little extra heating or cooling in the extremes but if it’s well insulated you might not also. I just know we get some pretty crazy temps in the Midwest in the summer and winter so that’s at least a good place to start.

Thanks for the feedback. Do you think I should run it to the bottom of the grow room? The laundry room is only like 4 feet away, so a good exhaust should pull proper air back to it.

I would try to avoid pulling air from the house. Your heating and air conditioning system is designed for specific square footage you’ll be making a bigger platform for it to operate which in turn makes it cycle more often and is extremely hard on it.
I grow in the garage rooms 10x10its loosely put together with straight up TPO framed 2xs top and bottom similar to a picture frame. i pull air from the garage for ventilation. The room has no insulation but the garage does. It’s been below freezing lately and the room with lights out don’t get below 65f. I run 2CMH at 350w a piece and 2HPS at 1150w a piece. Cooling I use this LG Home Depot portable A/C and vent it into the attic so I’m not heating the garage. dont forget your charcoal filter and your dehumidifier all these tools are required to have a successful grow experience in my honest opinion. I no it all sounds expensive but think of it this way bugs are free:) happy growing!!

Awesome, I think I’ll be able to direct the cooled air properly with some ducting and a controller to my grow room. Thanks for all the help!

Another thing you may want to consider is adjusting your growing window to line up with those median temps, not too hot, not too cold. I’m growing in a one car slot in my garage that I partitioned off. I start in September and grow through the winter, finishing in the spring. Now it may not get as cold here in Northern California, (rarely freezing) but just as hot or worse than many places in the summers 100+ continuous. Also what I’ve done is to have both blooming and veg’ing going on at the same time, (three tents) but offsetting the timing so that I’ve always got lights on. This relieves the need for aux heat needed by just running during the day, also avoids minimizing peak electrical use (remember California). Another thing I concentrate on is keeping the RH in check, running both a humidifier and dehumidifier as necessary. But I’m totally led (cobs) for bloom and T5 for veg, so more variables... With all that I keep tent interiors between 65-80 degrees, constantly exhausting all tents through ducting to a central 6” fan and out back into the space through a phatt charcoal filter.