Ask How Many Shingle Tabs Your Inspector Lifted

Many homeowners picture a roof inspection as someone walking the roof and looking it over. On a St. Louis roof, though, much of what decides whether water gets in is out of sight from a ladder. The seal strip under each shingle tab and the nails under the tab edge matter for wind and leaks, and a glance from the eave cannot tell a bonded tab from one that has let go. That is why a careful inspection includes a sample of shingles lifted by hand. The number lifted, the slopes they came from, and the photos taken of each one decide how much the findings are worth. This page covers what to ask about that sample before the inspector packs up.

Why the inspector has to lift tabs

An asphalt shingle tab is held down by a factory seal strip along its underside and by nails placed under the course above. From the ground, or from the ladder, a tab that has come unbonded often looks exactly like a tab that is still sealed. Lifting a tab gently shows whether the strip has bonded to the course below, whether the nails sit where the spec puts them, and whether the mat under the granules has cracked or gone brittle. Lifting also lets the inspector see granule loss on the exposed face of the shingle, which a surface look often understates.

What a sample can and cannot show

A sample is a set of spot checks. It describes the condition at the spots that were lifted, and nothing more. It cannot prove the condition of every shingle on the house. Sun, wind and rain reach each roof slope differently, so one slope rarely stands in for another, and a valley or a spot beside a pipe penetration can behave unlike the open field around it. A sample that is honest about its limits says where it was taken. A sample presented as the whole roof has hidden its own gaps.

The sample is also not a verdict on how long the roof has left. It is evidence about the spots lifted. Read it that way and it becomes useful: it tells you what to look at next, and where the next check should go.

Six questions to ask before the inspector leaves

You do not need to know roofing to ask these. The answers should come back as numbers, places and photo references, not as adjectives.

1. How many tabs did you lift in total, and how many came from each slope?
2. Where on each slope did you lift them: low courses at the eave, the middle of the field, near the ridge, beside valleys, and beside pipes or vents?
3. What did you check on each lifted tab: seal bond, nail position, mat condition, and granule loss?
4. Were the lifted tabs photographed, and do the photos show the slope and the location on the roof?
5. Did any tab fail to seal, and is each failure recorded as its own finding?
6. Did anything you saw on the lifted tabs suggest the sample should be widened on a particular slope?

What to watch for while the lifts are made

You can watch from the driveway. Each lifted tab should be raised gently, not pried, and set back in place when the check is finished. A tab that resists, then lets go with a small tear of asphalt or granules, has been bonded. A tab that lifts with no resistance and no residue has likely lost its seal. Look also for nails that sit high, low or crooked beside the tab edge. Ask the inspector to point out any tab that does not release cleanly, and ask whether it was counted as a finding. The report should say which kind of tab it was, not lump them together.

Where a sample gets thin

Weather is a common reason a sample comes up short. On a cold morning the shingles stiffen, and a seal strip that is only lightly bonded may not release cleanly. An inspector who lifts a tab in that condition can crack it, so a careful one may skip the lift and note why. Wet shingles are slippery, granules hide under water, and little useful can be read from them. A steep pitch can make the far slope hard to work safely, and the easy option is to lift on the slopes that are simplest to reach.

None of these reasons is a problem on its own. The problem is a skipped area that does not appear in the report. Ask the inspector to name every slope and area that was not sampled, and the reason for each one. A slope that was not checked is still a finding, and it belongs on the page with the others.

How the sample should appear in the written report

The report should turn the sample into a list you can follow. Each lifted location should carry a slope label, a short description of the condition, and a photo reference. Unsealed tabs should be counted and located, not described as "some" or "a few". If the report says a tab was unsealed, it should say which tab, on which slope, and where the photo is filed. A report that cannot be checked against the photos is only a summary, and a summary is harder to act on when the next storm arrives.

Keep the photo index with the rest of your roof file. Photos taken on a dry day, with the slope label visible, keep their meaning a year later, when you are comparing them with what you see from the ground.

If the sample looks thin

If the sample is smaller than you expected, or a slope is missing, you can ask for a re-check. Ask for it in writing, name the slope, and ask for the lifts to be made on a day when the shingles are dry and the air is above freezing. This request is ordinary. Keys Roofing can be reached at (314) 220-2333 to ask how a sample will be taken before the visit, and that question should get a direct answer before anyone climbs the ladder.