How do you set a shower pan in an RV?

[BradKW]

Anyone know what the proper way to set a residential shower pan in an RV is?

In a home, you set it in a sand mix pour, which supports the pan. Worth mentioning that when you find cracked pans, or read reviews complaining what a terrible product pan X is, odds are near certain that this step was skipped or not done properly.

But in an RV there's so much movement, I feel sure the pour would break up. Perhaps that doesn't really matter so long as it's contained, but I'm not confident about that...

 

[Every Road Leads Home]

Are you talking Fiberglass pans? I've always filled mine with spray foam, have never had one crack and makes them feel pretty sturdy. I think it would hold up equally well in a vehicle.

 

[BradKW]

I was thinking about foam, but wasn't sure if it'd hold up to being stood on over and over. While I have sweated off some pounds working weekends in this heat, I'm still weighing in at 210#...

 

[ahh_me2]

My Pan/tub came with a large piece of white styrofoam around the entire bottom load bearing area, however I would replace it with styrofoam SM (blue or pink)
If I decide to use it.
Since everything in an RV will tend to move/twist/bend however slightly, I would be more concerned about having too rigid a structure, it needs to have some give somewhere.

 

[Every Road Leads Home]

I was thinking about foam, but wasn't sure if it'd hold up to being stood on over and over. While I have sweated off some pounds working weekends in this heat, I'm still weighing in at 210#...

I've had 185 lbs in mine daily going on 5 years and still going strong.  Was planning on copying it if/when I do my trailer conversion.  It has a little give but def feels solid and not like it's going to break.  The one at my girlfriends house feels like it's going to break everytime I step in it.  Def nothing under hers except air.  I would think starting with a bit more expensive than the lowest end ones would be a good start too.

 

[Mobilesport]

Are you talking Fiberglass pans?  I've always filled mine with spray foam, have never had one crack and makes them feel pretty sturdy.  I think it would hold up equally well in a vehicle.

Spray foam would hold your weight easily and it's easy to work with. 
@Every road leads home  , I'm just curious what technique do you use to prevent the pan from rising when the foam starts expanding and putting upword pressure on it ?
You would have to keep the pan in place until the foam is partially cured.
I'm thinking something as simple as a couple of 2x4s mounted very securely across the area above the pan to prevent the pan from rising above your desired height , and then after the foam dries just remove the 2x4s

 

[AngryVanMan]

You can get higher density two component pour foams that would work well for applications like this, used often in the marine industry. I'm not aware of any foam that is spray applied that could be as dense, if you want to try and go go overkill on it.

 

[Every Road Leads Home]

Spray foam would hold your weight easily and it's easy to work with. 
@Every road leads home  , I'm just curious what technique do you use to prevent the pan from rising when the foam starts expanding and putting upword pressure on it ?
You would have to keep the pan in place until the foam is partially cured.
I'm thinking something as simple as a couple of 2x4s mounted very securely across the area above the pan to prevent the pan from rising above your desired height , and then after the foam dries just remove the 2x4s

I had access below my pan in the basement so I drilled a few holes in the floor where the pan was going, set it in place, screwed it into the studs through the flanges and then sprayed in the foam from below in the crawl sace.  I used a two part foam kit I bought from a local insulation place.  It was around $90 and came in a disposable set up....tank, 5' hose and gun.  It mixed it as it was coming out so it was a one time use thing.  It had a surprising amount of foam in it though, was able to do the pan and the stud walls around the surround.  The surround faced the bedroom so figured it would cut down on the noise if someone was showering while someone was still sleeping and worked great.  Can barely hear the shower when in the bedroom.  

I would do it the same in a vehicle and spray it in from underneath, although as AngryVanMan mentioned, a two part marine foam you pour into the pan might even be a better and easier option.