Forum Discussion

jcarter1976's avatar
jcarter1976
Explorer
Apr 16, 2021

Roof Replacement

I am gearing up to replace the roof on my 40ā€™ Salem and I have been advised not to replace the roof vents. The logic being that the fewer penetrations one has in their roof, the fewer leaks one may encounter in the future.
I get the rationale but Iā€™m dubious about not having any upward ventilation. Does anyone have any experience with an un-ventilated RV?
  • Example of what I am talking about..



    This damage was not caused by roof vents, it was caused by..



    Which is the trim..

    The caulking under that trim had gotten hard and cracked and the previous owner was too lazy to remove the trim and replace the caulking so they used everyones favorite fix in a tube..

    Silicone..

    The silicone didn't fix the issue and kept on leaking until I bought the trailer and when I stripped back the rotted paneling it was leaking like a sieve when it rained..
  • B-n-B wrote:
    I would say it has less to do with the holes in the roof (unavoidable), and more to do with the proper maintenance and sealing of said holes.


    Correct.

    Proper maintenance is key, doing maintenance on a regular schedule by removing and replacing old dried out cracked caulking and replacing with new fresh caulking will go a long way in keeping your RV leak free..

    Not eliminating holes from roof vent in the roof.

    Either do the routine maintenance yourself or hire it out, should be looked over at a minimum of once per yr.
  • B-n-B's avatar
    B-n-B
    Explorer III
    I would say it has less to do with the holes in the roof (unavoidable), and more to do with the proper maintenance and sealing of said holes.
  • valhalla360 wrote:
    Gdetrailer wrote:
    Using that "logic" one would want to get rid of the fridge vent, the A/C unit(s) and the black and grey tank vents, then you have zero holes to deal with.


    That would be awesome and would result in trailers that last much longer.

    It's nice to say if you are scrupulous about sealing it's not an issue...but reality is a large percentage of RVs go to the junk yard due to leaks, so clearly it is a problem.

    Retrofitting an existing RV would be difficult as you would need to figure alternatives out. But if you have good mood lighting already, skipping some or all of the roof vents would not be a bad option.

    For new construction, it's not nearly as bad:
    - Skip the vents and skylights and add LED strips around the ceiling. Actually a lot of RVs have already done the LED thing and with power consumption so low, it's really not an issue running them to compensate for the lost natural light.
    - Fridge...they are already going there with 12v fridges that require no external ventilation becoming the new standard.
    - Air/con units could do minisplit with the condenser on the rear bumper and no roof penetrations.
    - Tank Vents could be done with small wall mounted outlets.
    - A frosted side window in the bathroom, potentially with a fan would handle shower humidity.

    None of this would be particularly expensive to implement on a new production unit.

    Side benefits:
    - Slightly lower profile to get under low bridges/tree limbs.
    - Maybe a touch more aerodynamic for better fuel economy.
    - It would make one piece fiberglass or aluminum roofs a cheaper option which would again increase long term water tightness.


    :R

    You do realize the part of my post you snipped was a joke?

    Even with zero roof penetrations you have something like 100 holes in the roof membrane, right?

    The roofing material folds down over the side wall, then the trim strip is applied over the roofing material on the side wall..

    That is a potential leak that is real and that is where most of the water infiltration happens.. You have at least 40 holes on each side of the roof, not to mention all the holes from the end trim strips..

    The cold hard reality with RVs you need to constantly check the caulking on a regular schedule, replace when caulking ages.

    It is called "PMs" or Preventative Maintenance.

    So in reality, removing all of the holes on top of the roof nets you zero reduction in potential leaks. In fact, I would rather have a leak show up at a roof vent instead of having a hidden leak on the sidewall trim.. That side wall trim can leak for yrs and you will never know it until it pools up and rots out the floor far, far away from the real source of the leak at the trim.

    Seen considerable rot damage on both of the trailers I have rehabbed that came from leaks on the side wall trim. Just because that trim has a vinyl cover in place covering the screws, it doesn't mean that water can't leak through. That trim uses and depends on the same butyl rubber caulking and it fails after a couple of yrs.
  • Gdetrailer wrote:
    Using that "logic" one would want to get rid of the fridge vent, the A/C unit(s) and the black and grey tank vents, then you have zero holes to deal with.


    That would be awesome and would result in trailers that last much longer.

    It's nice to say if you are scrupulous about sealing it's not an issue...but reality is a large percentage of RVs go to the junk yard due to leaks, so clearly it is a problem.

    Retrofitting an existing RV would be difficult as you would need to figure alternatives out. But if you have good mood lighting already, skipping some or all of the roof vents would not be a bad option.

    For new construction, it's not nearly as bad:
    - Skip the vents and skylights and add LED strips around the ceiling. Actually a lot of RVs have already done the LED thing and with power consumption so low, it's really not an issue running them to compensate for the lost natural light.
    - Fridge...they are already going there with 12v fridges that require no external ventilation becoming the new standard.
    - Air/con units could do minisplit with the condenser on the rear bumper and no roof penetrations.
    - Tank Vents could be done with small wall mounted outlets.
    - A frosted side window in the bathroom, potentially with a fan would handle shower humidity.

    None of this would be particularly expensive to implement on a new production unit.

    Side benefits:
    - Slightly lower profile to get under low bridges/tree limbs.
    - Maybe a touch more aerodynamic for better fuel economy.
    - It would make one piece fiberglass or aluminum roofs a cheaper option which would again increase long term water tightness.
  • Using that "logic" one would want to get rid of the fridge vent, the A/C unit(s) and the black and grey tank vents, then you have zero holes to deal with..

    Reality, however, properly done your roof vents pose no more problem for future leaks than the trim that covers the roof to side wall..

    Not to mention then you would have the ugly openings on the inside where the roof vents used to be that you would have to cover up..

    I do use the roof vent in the bathroom when taking a bath, I did eliminate the roof vent over our master bed when we rebuilt our TT, wasn't a fan of the light that came through it early in the morning at the crack of 5AM.

    It is a personal choice and up to you.