The mystery of the leaking skylights, and other unwanted drips

• By: davew
• On: 08/14/2008 13:55:09
• In: Keeping a Roof Over Your Head
• Comments: 1

A few years ago, we did a kitchen renovation.  Large room, Euro-style, floor to ceiling glass sliding doors, skylights.  The roof wasn't quite flat, it had a very slight pitch. The  skylights had been installed on a very low curb so we increased the curb to approximately a 4 on 12 pitch, which is the minimum that the manufacturer will warranty for leaks.  We did a torch roll roof, which is common for flat roofs, and also up and around the skylights.  

It took a couple of years before the drips started.  Whenever it would rain, there'd be water leaking into the kitchen.  We resealed the skylight units multiple times.  The leaks stop, then start again a few months later.  It seems that the seasonal temperature changes constantly cause the drip to reappear. Also, strangely enough, there are 3 skylights and they seem to take turns leaking. 

We're now planning on installing a much higher curb and increasing the pitch to a minimum of 6 on 12.  One of the reasons we want to change to the higher pitched curb is so we can use standard roof shingle and not torch roll, which is melted directly to the skylight.  The reason for this is it would seem that the change in temperature is causing a  break in the bond between the roof material and the aluminum flashing.

One of the many "might as wells" when we were doing this reno was to put ceramic tile over the flat roof area as it made for a fantastic place to have an outside deck with plenty of privacy and a great view.  Since then, we've had a calcium and lime deposit problem.  It seems that the calcium and lime in the cement under the tile is leaching out, causing an ugly white drip on the wood siding and decking below.  At first the drippings from the ceramic deck caused the aluminum gutter to rot out, actually burning holes in the aluminum.  We then changed it to a PVC gutter system but as is typical with PVC, because it expands and contracts so much and can't be sealed permanently, it tends to also drip this white residue. 

We finally have come to the realization that the easiest way to fix this problem is to remove the tile and install a pea gravel coating on the deck which hopefully will give the effect of sitting on the beach. We'll be using pea gravel not only for the beachy effect but the light color will reflect heat and UV rays keeping the kitchen below cooler and adding longevity to the roofing material.

We'll let you know how this goes.  If anyone has encountered similar problems, especially with the calcium and lime drip from ceramic tile, let us know.