Everything on your roof – except for your air conditioner, which uses a thick foam gasket – is waterproofed with a butyl tape gasket underneath (where you can’t see) and a self-leveling cap sealant on top (what you can see). Flashing details vary by manufacturer, but the gasket-and-cap-sealant method is the de facto standard for RV construction.

It’s not like your house roof, which naturally sheds water because of overlapping shingles. RV roofs don’t have shingles. The gaskets and cap sealants do all the work. If these fail, your roof will leak.  

How Often Should I Inspect My RV Roof?

I recommend conducting a thorough inspection of your roof twice a year: spring and fall. Inspect your cap sealants for signs of failure: cracking, peeling, flaking, bubbling, etc. If you see any signs of failure, you should scrape off the old sealant and replace it with new sealant. Don’t just look – touch and feel!