Well..il start at the beginning..wife and i had a baby..i needed to take my home back space wise so i moved my whole grow outside into a shed...i bought a 12x20 wooden utility shed. .sealed cracks layed insulation and drywall..finished it and painted it.. added a inner wall so i have 12x12 flr and 8x12 veg..got all the proper permits and ect. to run power out there.. long story short its nice..clean..and ready to rock..its been a 5month project and $8000 total ive paid...now it seems im having issues.. ive been growing since 2011..im so overwhelmed with everthing honestly i feel like a noob farmer and its way stressful ..temp control has been a trip..ive seen as low as 58 and high as 93..rh% as low as 20 and high as 100..light leakes from veg to flower..not a leak but a glow..timer bumped at one point so 10hrs into dark lights come on for a hour then back off for a hour then start up for the day...trying to get co2 ppms correct..man im overwhelmd almost makes me wanna cry lol..in my house i never had these issues...well today took the cake when saturday we had our 1st snow here in michigan this year with 10in..i open up thus mourning to see my whole veg room floor soaked with condensation..now wtf do i do..shed was built lvled out and droped off outback..NEVER DAWNED ON ME TO INSULATE THE FLOOR...now its there with power lines hooked up from under ground and its courners are tied to augurs to hold it down due to winds (city code stuff)..so now what..someone said put straw bails around it so cold air dosent flow under it and i considered building a insulated floor inside on top of the preexisting floor but im so far invested out my own pocket that i cant swing it till i get some real harvest monies back..also dosent help my wife has some thing neg to say every time i spend more money on this lab so im stuck were im at till i can produce and make some money back...what can i do here cause im exhausted here mentally....
Some pictures would help, but in absence of those, cheap solution. Sandbag around the outside bottom, spray expanding foam on the inside seam then immediately drop some pond liner (really heavy duty black plastic) on the floor extending about a foot or two up the side. Bet that could get you through the winter.
there are spray in insulations. Sealing up the gaps under the shed and spraying in insulation could work depending on how serviceable it might need to be and how big the gap is. you could use sheeting like on trailers or sandbags like suggested above. also sealing the interior floor would be a good idea.
You can get Styrofoam sheets pretty cheap, put those on the floor, 3/4" is r4 and a 4*8 sheet is 12.00 in Canada so you should get it cheaper. It won't last forever but it should last your grow.