Gravel under trailer?

[mrstovar]

We bought some land and had a mobile home moved on. The land is on the mountain side, with lots of water running off the mountain over the property, plus several springs on the property so its very wet. The folks that installed the mobile home lay gravel and put a heavy plastic under the trailer and told us we should divert the water so it doesn't flow under the trailer and we would be fine. My husband, though, had other ideas. He was convinced that the water flowing under the trailer is not the problem, rather the lack of gravel on top of the plastic! This in spite of several different local folks that know trailers looking at our mobile home and all telling us the same thing--that we do NOT need gravel on top of the plastic but we do need to divert the water.
Well, this week when we were looking at our property and discussing what needs to be done, suddenly my husband said the FIRST thing we need to do is divert the water--like yesterday! so of course I agreed and we found a contractor to do that for us immediately and I'm so relieved to have that done finally.
However, my husband is still insisting that we put gravel under the trailer.The highest quality gravel. He is sure that we will still have a bit of water under the trailer and says he needs the bed of gravel underneath in case he ever has to crawl under there for some reason, so that he's not lying in water. Not only am I concerned about the needless expense when we barely have the money for all the truly needful projects but I wonder if gravel might puncture the plastic or have other undesirable consequences.
Is there anything I might say to him to convince him not to lay gravel right now, or is there anything you can say to me to help me be more comfortable with it? He does not believe that metal skirting will keep the water out, nor a small gravel berm right at the trailer. He does not agree to a bed of sand instead. He's insisting on gravel all underneath the trailer!

[1987Commodore]

The skirting will not keep the water out, nor will a gravel or sand berm. The plastic on the ground needs to extend up the inside of the skirting so water will go under the plastic. I had a couple of spots under mine where the water would pool on top of the plastic, so I just put a knife slit there so water could drain out of the depression. The goal is to keep it as dry under there as possible, but remember it is outside at ground level so it will not be perfectly dry. As for gravel on top of the plastic, I would rather lay on the plastic than a gravel bed. The gravel over the plastic would hold water in place rather than letting it evaporate easily. You need adequate ventilation underneath so it can dry out.
Diverting the water is the first priority,

[Greg]

Well since the ship that had the full concrete pad on it already sailed (and probably sunk) your next best option to keep things as dry as possible is proper drainage and ventilation. I would make sure that the ground is sloped so the water will run away from or around the home. Make sure you have a MINIMUM of 1sq. foot of ventilation per 150sq. foot of floor space. If it is wet don't be afraid to double or triple that. I have screen panels that I install in warm weather.

Greg

[mrstovar]

We dug a trench the length of the upper side, leading to the culvert under the driveway. Thanks.

[JD]

More than just a trench, the ground should have a downward slope away from the house, to the trench. The gravel could damage the plastic sheeting and would not keep anyone from getting wet. The gravel will compact, move and spread when crawling around and you will still be in water. This also defeats the objective of NO water collecting under the home. That is what needs to be done. Then when working under the home, lay out cardboard to crawl on so you don't tear up the poly sheeting. Also keeps gravel from digging into your knees and elbows.

[mrstovar]

Hi, J.D., yes, no gravel is going into the crawl space. Of slope and water, it is now going around the back of the building. Thanks, and for the tip about cardboard.