Spray foam

[Daisyfuel]

Daisy Fuel here , I have what may seem to be a stupid question, is there any way that spray foam can be applied under the bus , in between the floor braces , instead of me losing vertical space on the inside . I’m 6’3
And I would sure like not to have to raise the roof , because it is also getting a roof deck . Any thoughts on this subject ?
And thank you Skoolie net , you are the best

[warewolff]

Yes, but it gets pretty nasty and most of us opt for a roof raise instead. Good luck cleaning oil and road grime off spray foam under the bus...

[Tango]

Foaming from below is tricky as anything that may eventually need servicing absolutely must be kept in the clear.

[ComfortEagle]

Originally Posted by Daisyfuel

Daisy Fuel here , I have what may seem to be a stupid question, is there any way that spray foam can be applied under the bus , in between the floor braces , instead of me losing vertical space on the inside . I’m 6’3
And I would sure like not to have to raise the roof , because it is also getting a roof deck . Any thoughts on this subject ?
And thank you Skoolie net , you are the best

I haven't seen it done here on skoolie.net, but I have seen it done on a travel trailer. The installer sprayed foam and then sprayed a healthy coat of undercoating over the foam once it was cured.

I am also looking to minimize lost ceiling height; I will not be doing the rigid foam insulation sub-floor sandwich. My Gillig has very large pass thru storage bays and I intend to spray foam the underneath of the floors in those bays (the "ceilings" of the bays).

For the rest of the under floor areas and entry stairs, I am looking for reasons NOT to spray foam and then undercoat it. I intend to do a thorough cleaning and restoration of the entire undercarriage of the bus prior to doing the foam.

This technique will also allow me (force me?) to do the spray foam in two sessions (interior and exterior) that can be done at different points in the build. This of course is only a "plan" at this point, but again, it sure seems like a viable solution to me...

[o1marc]

As an installer I would be looking to double the bill if I had to work on my back in a confined space dealing with all the details under there. Just something to consider.

[joeblack5]

The several spray foam jobs we did are always were done lousier then you would do it your self. The only way to get the desired quality is diy. I am very curious how the ceiling profiles will hold up now that they are surrounded by foam but not filled with foam. Excellent condensation / rust spot. Same about all other cavity filling. The spray foam contractors are so much in a hurry that it is more likely that they close the cavity of then that actually filling the cavity.



later J

[2martins]

What he said. Also, apparently bugs can decide to live in it, as can rodents. I found several rodents had been living in the spray foam insulation inside of the hot tub that came with my house. It was disgusting. It will also make working on things a lot harder under there. If you are going to raise the roof anyway it's not worth it.

Originally Posted by warewolff

Yes, but it gets pretty nasty and most of us opt for a roof raise instead. Good luck cleaning oil and road grime off spray foam under the bus...

[2martins]

Originally Posted by ComfortEagle

I haven't seen it done here on skoolie.net, but I have seen it done on a travel trailer. The installer sprayed foam and then sprayed a healthy coat of undercoating over the foam once it was cured.

I am also looking to minimize lost ceiling height; I will not be doing the rigid foam insulation sub-floor sandwich. My Gillig has very large pass thru storage bays and I intend to spray foam the underneath of the floors in those bays (the "ceilings" of the bays).

For the rest of the under floor areas and entry stairs, I am looking for reasons NOT to spray foam and then undercoat it. I intend to do a thorough cleaning and restoration of the entire undercarriage of the bus prior to doing the foam.

This technique will also allow me (force me?) to do the spray foam in two sessions (interior and exterior) that can be done at different points in the build. This of course is only a "plan" at this point, but again, it sure seems like a viable solution to me...

This is one of the few instances in which I can see this working. I have also considered doing the entry stairs and then covering with undercoat because there isn't anything else there to worry about and no other good way to insulate.