Here is the counter space dedicated to my ferments which benefit from fermenting around 66-68 degrees. I cover the area with a dark cloth to prevent light exposure and help keep fruit flies away.
Here is the chamber I created once the weather began to cool. I cleared off a shelf in my kitchen, placed a heat mat with towels on the bottom and placed a couple of cookie sheets over the mat to help catch any overflow and prevent the jars from sitting directly on the heat source. The towels help to disperse the heat. I have the heat mat plugged into a timer to intermittently come on and have it programed to come on more frequently during cooler times, so I can easily maintain an environment of 70-72 degrees. We insert a thick insulating make-shift door or cover to minimize heat from escaping and cover that with a pretty cloth.