No, I have not used a separate fan but it's not a bad idea. The heater has a fan but it is pretty weak, so for the most part the heat rises up in the center of the enclosure and disperses. The plants are up on tables that run along 3 sides of the enclosure, some tougher/stock plants go on the floor. I'm sure there are cold areas especially along the walls, but I've been using this for about 5 years now and haven't suffered any winter losses. Well, let me modify that...during one of those really cold winters we had a few years ago, I did lose the apexes on a trident maple and a sweetgum. I'm not sure what cause that.
I use a rotating oscillating fan with mine so it disperses the warm air around. I also use a venting fan on one end of my storage house, with electric vents on the other end on the cooling side of the thermostat controller I linked to. It comes on at a set temp that you can also choose in addition to the heating side of the unit. Then if it gets too warm, the vents open and outside air is sucked thru the house.
Judy, your shelter is actually a greenhouse, right? Can you remind us of the approximate dimensions?
I think it's probably 16x10? Here is a link to a thread on it.
Pampered much? On a serious note, your dedication is highly respected here 
I'd get you a nice spot on one of my warmer heat mats. I'm sure I could do an unglazed pot if I had to just for you...LOL.I once told Crystal if I were to pass and come back as a plant living under your care it would be fine by me
Grimmy
Ah yes, so not exactly a greenhouse but definitely plenty of windows, so more issues with heat buildup than I have to deal with. I could really use some kind of structure where I could keep plants cool but with decent light during the winter, as some of my trees that would benefit (like coast redwood) are weakening with time. I suspect due to lack of light during the winter.
The solexx is very helpful in this regard, as it spreads out the light instead of condensing it as windows or triple wall transparent would. You actually get higher light readings thru the whole space with the solexx. And far less heat as well. I use darkening shades for the middle of winter to keep it cool. The fan and vent are great for those sunny but cold days. As long as there are not lots of warm sunny days in a row, I'm usually ok. Of course if things pop early, then I've got the lighting, I just turn it on and go with the growth.
