Last year put up my very first GH - 6 x 8 from HF. Quickly discovered it's WAY too small. Attaching a 2nd 6 x 8 in the next couple of weeks -- with a walk-thru where it attaches to the first.
Not sure if anyone has tried attaching to GH and keeping one cooler- and how did it work?

I wasn't much of a GH gardener last year - not for lack of effort. Lots of things started out good and then just didn't make it. Had bug problems and just growing problems. I think some plants were too warm.
This year I'm going to keep the cooler loving plants in the 2nd GH and only let a little heat filter in from GH #1. I'm certainly not going to try to grow tomatoes again ! The things that did the best for me were peppers -- started in the GH and produced wonderfully when I moved them out. Tomatoes just flopped - always do. I had just hoped the GH would make a difference on that.
So my strategy will be different this year -- and I hope to grow lettuce, spinach and stuff like that in GH 2 - and just overwinter my lemon, herbs, dwarf figs & berry bushes in GH 1 (and if I'm lucky I'll start some seedlings late in spring just in time to plant outside. Time will tell - hopefully year 2 will be a miraculous improvement for my gardening abilities

Sounds like a great idea to have two GH zones. In larger GHs, a "curtain" is used to manage space and cut down on heating bills.

That sounds great, Carol. When someone contacts me or posts that they are considering building a greenhouse, the first suggestion I throw out is to build one twice the size they think they will need. More often than not (me included), we regret the size we built. It is amazing how a greenhouse opens up so many possibilities of growing exotic plants and starting seeds, or just getting amazing results with what one grows.

Yes @drdawg you are sure right about that. I thought 6 x 8 sounded great until I started loading it up with all my plants -- and "stuff". I suspect 2 of the 6 x 8 will still not be big enough -- haha -- but I will make it work. Husband is modifying so I have a walk-thru from one into the other -- and I want to have an outside door into each as well.

That sounds like a practical way to double what you have and it is nice to have your husband able and willing to do the walk-thru.

Carol, the heavy clear vinyl strips they use on warehouse doors would make an excellent curtain for your walk thru. Even a piece of solar blanket may work, but you may need to add some small weights to the bottom.

Great idea @Eric4home