- Car Care & Maintenance
Bathroom Dome Replacement on RV.
Leaking Bathroom Dome Repair for RV's
Leaking Bathroom Dome Repair for RV's
If you have a bathroom dome in your RV or motor home that is leaking it can cause damage to the wood paneling under the roof membrane. This water is working it's way under the PDM rubber roof membrane rotting the wood sub roofing. Sometimes a coating of rubber Lap Sealant around the bathroom dome can take care of the problem, but my leak was caused by the screws being rusted and dome was loose, so removal of the dome was necessary. Note: Plastic bathroom domes are different sizes and shapes, and this is a general replacement guide for any bathroom dome or vent hatch replacement.
To remove the dome you will need:
1.a tall ladder, a ten foot A-frame ladder is easy to work from and get on the roof to.
2.a putty knife to remove the old caulking,clothes
3.a screw driver to remove the screws holding the dome to the roof.
4. New lap sealant
Always be careful working on a ladder, wear the right clothes, and use the right tools to prevent accidents.
First remove all old caulking from around the dome with the putty knife. This will be time consuming as the dome needs to be clean and be careful not to break. Note: Most plastic dome get brittle over time and yellow, so take your time and do a good job and the dome will go on easer later. Once the putty is removed loosen all screws holding the dome to the roof, being careful not to puncture the rubber roof membrane. Once the screws have been removed use the putty knife to pry open the dome from the roof membrane, once again paying attention to dome and the roof. A solvent can be used in the final cleaning stage of the dome.
Inspect the roofing under the dome, sometimes the screws are rusty and the wood is rotten. To repair the wood use a thin layer of clear silicone caulk under the loose membrane and wood as a glue, and this will seal after drying. Note: Place a pice of wood over the hole and weights around the edge to hold the roof flat until dry.
Now we can work on the dome itself.
Clean the dome free of all caulking and dirt. If the dome is yellow you can use the headlight cleaning method to restore the white to the dome, or in my case, paint the dome. I wanted to add color to my roof line so I painted the dome a gold texture and this helped cover the old look to the dome and add color to my roof line.
Ready to replace the dome.
Remove the cover over the opening, check to see that it aligns correctly, and lays flat. If the old screws are rusty replace the old rusty screws with new screws one size larger than what came out. This will help hold the dome firmly in place, but before you do this, use a line of "lap sealant" the width of the lip around the dome of the roof where the screws attach the dome. A quarter inch thick bead is enough to get a good seal once the dome is secured to the roof. Note: use a lap sealant not caulking on the roof, silicone does not hold well on membrane surface.
Pay attention to the screws as they go into the wood frame so that the dome is a tight fit. Once the dome is secured on top the lap sealant, placed a bead of lap sealant on top of the lip covering the new screws and covering the edge of the dome, so it seals to the roof in one continuous bead. This may take several tubes of caulk but it is worth not having this problem again down the road. Note: I have found that putty tape, instead of lap sealant from a tube,covers large areas .
Make your way around the dome with sealant looking that all screws are covered and the edge of the dome is covered to the roof and the job is finished. Lap sealant only dries to the surface and takes several years to harden, and new sealant can be added afterwards if needed.