Perhaps you, like me, live in a house built to the 1940's-50's code for the crawlspace. Mine was built in 1966. Vented block foundation, plastic on the dirt floor, glass insulation under the floor between the joists. Nasty as all get out most of the time....and you rarely go under there.
If so, like me, (I live in a damp area) every few years you go under and use new rods to push up the fallen glass that dropped due to moisture in the summer season...condensation and all that.
I went under this year, after not going for about 5 years...what a mess. Well, years ago I investigated the "closed" crawl concept. It was gaining favor, but not totally proven. Now, studies have shown that it is the thing to do...even a retrofit is a good idea.
So, I can protect my house from mold and mildew, rot and damage, enjoy lower energy bills and better living conditions in the living area by conditioning the crawl space!! Lucky me.
I had an outfit called DryZone come out to look it over and tell me what they would do to improve it. No estimate yet, but from talking to others who used them, I figure they will be about $10K to do my 28' x 68' space.
BUT....not only do I get those great benefits above: it appears from their pictures of before and after that I gain a new room....I can use it for the trains!! Sure, it is only 22" tall, but oh well as they say! Nice and white walls and floors, no nasty glass insul or moisture, a great place - like gaining a room!
I am sure some of you have done the same thing! ;-) It stays a constant 55 degrees under there and humidity of 50% or less.....perfect train room!! Lots of room for guests also, if they are short.
I think I will do it! Greg