Under my emclosed front porch there is a crawl space with a dirt floor and concrete block walls. It has always been very damp and dank under there no water is leaking in I believe it's just condensation from the ground. This weekend I went under there and cleaned out some junk that was in there (old chain link fence, old wooden ladders, extra concrete blocks). My question is how can I go about making it less damp under there? It has an access door and a window on opposite ends and I was thinking of putting vents in them so air could flow through better, but my concern is in the winter the floor of the porch tends to get very cold it's insulated, but it still gets cold. Another issue is the baseboard heat from the porch goes down into the crawl space when it goes around the front door the pipe is wrapped with insulation, but I'm worried with the air flow it might get colder under there. I was also reading where you can put plastic sheeting down and this helps with cutting down moisture. Is there a specific type of sheeting you would use? Do you stake it down or just lay it down? My other thought was putting some sand under there to help absorb the moisture. Any ideas or thoughts you might have would be greatly appreciated.
It's standard practice in the UK to put down a layer of sand, plastic sheeting and then 4 inches of concrete under a suspended timber floor. This gives a base for the sleeper walls and helps prevent damp. The area is also ventilated. There will be heat loss which is why solid concrete floor are now preferred.