Quickly Identifying Unsealed Shingle Tabs

Posted by in Roof, Shingles, Simple Forensic Methods | June 19, 2017

Here is a quick and easy method to identify unsealed, partially unsealed, or poorly bonded shingle tabs or shingle strips.  But I must warn you, “DO NOT TRY THIS AT HOME UNLESS YOU ARE WILLING TO ACCEPT THE RISK OF DAMAGE TO THE SHINGLES.”  And, “CARELESS OR INATTENTIVE USE OF THIS METHOD COULD CAUSE DAMAGE TO THE SHINGLES.”

Since shingle tabs can be lifted by wind, I have recreated the conditions of wind using a blower to move air across the shingle tabs or strips, watching for movement of the tab.  When done properly, an unsealed or partially unsealed tab will lift slightly (see featured photograph and Figure 1).  Note, however, that a poorly bonded tab may unseal.

Figure 1 Tab lifts slightly with application of moving air across surface.

I use a low powered blower.  These are often called “sweepers,” are powered by batteries, are much smaller than leaf blowers, and put out much less air flow.  Also, do not start by placing the blower directly on the edge of the tab.  Hold the blower above the shingle and lower it slowly watching for movement.  Be ready to lift the blower if a tab is lifted too much.

Each roof is different and requires some adjustment to the method, so proceed slowly and carefully.

Unsealed tabs may be marked with chalk across the slope and then they can all be re-sealed.

I’ve been applying this method on my own roof and on those of friends and family.  So far, I haven’t had any damage except for the unsealing a few poorly bonded tabs which I subsequently re-sealed.  If carefully done, it is not easy to damage a shingle tab with this method, but I give warning because with a little inattention or daydreaming it may be possible to dislodge a tab that was already cracked or break a tab that was made severely brittle by age.

Well, if you DO choose to try this, “Happy hunting.”

And be careful up there.