Hey @Humanrob glad to see you pursuing the Idea of a sealed GH. For someone who prefers to grow sativa doms like we do I believe it's imperative. I used 1' square concrete pavers over a sand base for my floor and they work well. My cost to run a 80 pint dehuey was about $40 a month, minimal cost to insure Oct. Nov. finishing times. I was able to keep the humidity below 50% during these months.
Just to be clear -- there is no one amount that it costs. It depends on how new/efficient the dehumidifier is, how big the space is, how well its sealed and/or insulated, and things like how many plants are in there (if you have lots of plants in large fabric pots, they are going to put off large amounts of moisture, especially right after you water).
True, there are a number of variables to consider for my own grow. I thought it would be more $$ to run a dehumidifier in a sealed room. I'm pricing materials for my outdoor cover.
I know I've been talking about a greenhouse for a couple of years, but we have so many projects in the queue that this summer a greenhouse isn't going to make the cut. This year I'm going to try light deprivation (just using a hoop house), next year I hope the greenhouse makes it to the top of the list. I'll keep in mind the pavers, we've gotten pretty good at spreading/tamping/leveling the gravel and laying those out.
I look forward to seeing their progress!
