soil too cold indoor

I used a heat mat on my 120x120 but i wouldnt use it on a bigger one. it also depends on ho much electricity u can consume.if im not wrong mine is 150w. Another thing that i noticed,in my growing room,there a lor of humidity coming from the bottom of the structure since is not isolated. To make it short,if you have the same problem you can put some isolation under your tent, eps up to 10cm and you are good. in my small tent,i have a small heat mat for the night,barely i reach 20C°. I did not place it directly under the pot,but under the surface of the tent. Maybe for big situations is better a fan that produces hot air 🤷‍♂️ Good luck 👊🏽🍀