Water damage in a "B" (or lack thereof)?

Sprinter roofs are made of welded steel panels. We found that we had a leak in our 2006 Sprinter when we drove through a very heavy downpour. After looking at the Fantastic Fan assembly and other potential sources, we found that there was a small junction between the panels that had a faulty weld. We fixed it with boat sealing caulk and have had no problems since.

McK wrote:
As I understand, since at least 2006, the high top Sprinters, like mine, have had factory installed fiberglass roofs.

I've never had trouble with mine even that night in New Orleans when 8" of rain fell in 10 hours.

????? High top Sprinters are all uni-body metal. Low Sprinters by Sportsmobile with the push up tops may be fiberglass.

As I understand, since at least 2006, the high top Sprinters, like mine, have had factory installed fiberglass roofs.

I've never had trouble with mine even that night in New Orleans when 8" of rain fell in 10 hours.

Many Class C's are boxes with flat roofs made of a membrane sheet roofing or a coated applied roofing. In essence, in time they will fail faster, much faster, than any original metal roof or a fiberglass roof.

We bought a 5-year old B and had a frustrating leak in our Sprinter roof that took a very long time to pinpoint. We attempted many fixes - removed many blobs of caulk the previous owner must have put on - and re-caulked around antenna and fan installations etc.) No joy.

Finally we replaced the entire Fantastic Fan unit ourselves which seems to have solved the problem - no leaks during recent torrential east coast rains. We think it might have been a hairline crack on the plastic fan unit cover allowing water in.

No real interior damage, as the cabinetry is solid wood and the floor in that area is faux wood finish linoleum. Some water staining on the ceiling above the passenger door but that wiped off easily. We did pull out some surrounding insulation after removing the old fan, let the area dry out good, and then packed a lot of fresh stuff in before installing the new fan.

Many Class B RV's don't have the van's original metal roof, it is a fiberglass one added when the roof is raised to allow a person to stand up in the van. The Sprinter based Class B's do keep the original steel roof though, as they are tall to start with. On some Class B's there sometimes is a problem with water coming in from the roof mounted air conditioner moisture, but this is a very rare occurrence.