Metal roof leak

[Wes Tex]

This may have been "discussed to death" in another thread, but I have a leak in the middle of my 30x40 metal roof garage. The leak is coming from where the two corrugated metal roof panels overlap. I only have about a 24 inch slope for 30 feet of roof. (Snow build up is not an issue in west central Texas.) When the roof was installed as an add-on to an existing RVport, foam, precut insulators were placed between the top and bottom metal sheets. For the first five years all was fine. Now a big rain apparently causes the water to flow back between the two roof panels. (The overlap is about 8-10 inches.)

I really don't want to undo the panes and reinstall the insulators, so I have tried different calking to seal the edge where the top panel joins the bottom panel. So far I have found NP-1 to last the longest before breaking down. (No, I have not resorted to flexseal.) I am looking for something that might be better? Is this a hopeless cause?

 

[readhead]

Foam closures would not have been the right product for the lap. Most manufacturers require two rows of butyl tape with lap screws. On that low of a slope there should have been butyl tape on all the rib laps with lap screws.

Resealing the laps is not that hard. Remove enough screws to roll the sheet back, clean the lap area, install the tape and screw it down. Make sure you get some goof screws because the old ones will strip out when you put it back together. Single sheets would have been the way to go but the builder probably didn't want to go to the trouble to do it right.

 

[why worry]

X2 !!

 

[James-W]

Maybe this is a stupid idea, but possibly some of that Flexseal stuff would work to seal the leak. It even comes in a spray can so you could spray it on.

 

[bob15]

I have had good luck using Eterabond products that are made for RV roofs on both my metal build roof panels and my snowmobile trailer: http://www.eternabond.com/RV-Leak-Repair-Products-s/22.htm

 

[jubilee]

Brushable silicone.The good stuff is around $300 gallon, but it works and lasts for years.

 

[jabberwoki]

Sickaflex has worked well for me.

 

[RivennHewn]

Sickaflex has worked well for me.

Sika and forget it

Also, leaks on metal roofs can start 30' away and travel. Are you sure your ridge is intact and shedding water?