How to Tell Your Roof Was Installed Correctly

You just spent somewhere between fifteen and forty thousand dollars on something you cannot really see from the driveway, and the crew is packing up their trucks. You are not being picky if you want to check the work before you sign off on it. You are being an adult about the largest exterior purchase most homeowners ever make. Here is exactly what to look for, and you do not need a ladder to do most of it.

Before you release final payment

A final walkthrough is a normal part of a roofing job, not an accusation, and any contractor who treats your questions as an insult was hoping you would not ask them. Walk the job before you sign the invoice and before the crew leaves the street, because anything genuinely wrong is far easier and cheaper to fix while the staging, the ladders and the extra shingle bundles are still on site than it is a week later when everyone has moved on to the next job.

This is also the moment the checklist below is built for. Use it on us, and use it on anyone else's crew too.

What you can check from the ground

Most of what tells you whether a roof was installed correctly is visible from your own lawn. You do not need to climb up there, and we would rather you did not. Walk the perimeter of the house and look for these:

• Straight, even shingle courses. The horizontal lines of shingles should run straight across the roof with no waviness and no stair-stepping where one row drifts up or down relative to the next.
• Consistent exposure. Each shingle should show the same amount of surface to the weather as the one next to it. Uneven exposure usually means the courses were not chalked and measured properly.
• Shingles lying flat. No corners lifting, no edges curling upward. A shingle that is not sealed down is a shingle the next nor'easter will find.
• A clean, straight ridge line. The ridge cap should run the full length of the ridge with even spacing and no gaps or wavy sections.
• Drip edge visible at eaves and rakes. A thin strip of metal should be visible along the bottom edge of the roof and up the gable ends. If you cannot see any metal edge at all, ask why.
• Valleys clean and consistent. Where two roof planes meet, the line should be straight and the shingles trimmed evenly on both sides, not ragged or overlapping unevenly.
• New metal flashing at the chimney and any sidewall, not a smear of tar. You should see actual step flashing pieces and counter flashing at a chimney or where the roof meets a wall. If what you see instead is a thick black smear of roofing tar as the primary seal, that is a red flag. Tar is not flashing, it is what flashing gets replaced with when someone is in a hurry.
• Pipe boots that look new. The rubber or plastic boots around vent pipes should look fresh, not cracked, sun bleached or reused from the old roof.
• Gutters intact and properly reattached. They should be running true, hanging level, and free of dents from the tear-off.
• No debris left behind. No nails, no shingle offcuts, no wrappers or scraps in the flower beds, on the lawn, in the driveway or in the street. A magnet sweep should have caught the nails specifically.

What to check from a window or an upstairs vantage point

If you have a second floor window, an attic dormer or a neighboring vantage point that lets you look down on a section of the roof, take a minute up there. From above you can often see things the ground view hides: whether the ridge cap sits centered and tight, whether valleys are trimmed cleanly, and whether any section looks patchy or mismatched in shingle color or alignment compared to the rest. You are still not going up a ladder for this, you are just changing your angle.

What to check in the attic

This is the part almost nobody thinks to do, and it tells you more than the view from the lawn. Bring a flashlight up into the attic, ideally on a bright day, and look for:

• No daylight through the roof boards. If you can see pinpricks of light coming through the deck anywhere, that is a gap that should not exist.
• No new nail points poking through where they should not be. An occasional shiner near the ridge can happen, but a scattering of misplaced nail tips through the deck is sloppy work.
• Insulation undisturbed. It should be lying the way it was before the crew started, not kicked around, compressed, or blown into a corner.
• Soffit vents still clear. Look toward the eaves where the roof meets the outside wall and confirm the intake vents are not blocked by insulation or debris. Blocked soffits choke the ventilation the new roof needs to work correctly.

Go back up again after the first real rain and look for any new staining on the sheathing or the insulation. A dry attic after a hard rain is one of the best confirmations you will get that the flashing and underlayment were done right.

What to check after the first heavy rain

A gentle straight-down shower does not test much. What actually stresses a roof is wind-driven rain, the kind a Long Island nor'easter delivers sideways at the eaves, valleys and any wall flashing. After the first real storm, walk the same interior spots you checked before: ceilings below valleys, around the chimney, near any skylight, and the attic itself. No staining, no damp smell, no soft spot in a ceiling is exactly what you want to find, which is to say nothing at all.

The paperwork check

The job is not finished until the paperwork matches the work. Confirm you have, in hand:

• The workmanship warranty, in writing, not a verbal assurance.
• The manufacturer's product warranty, registered or supplied to you directly.
• Confirmation the permit was closed out, and that any required inspection was signed off.
• A final invoice that matches the scope you agreed to, not a number that has quietly grown.
• Any change orders during the job documented in writing rather than agreed to verbally on the driveway.

If you want to know what should have been in the original proposal so you can compare it against what actually got built, see what a roofing quote should include, line by line.

Things that look wrong but usually are not

Not everything that catches your eye is a defect, and this page is not trying to turn you into someone who distrusts a good job. A few things are normal:

• Slight color variation between shingle bundles. Asphalt shingles can vary a shade between manufacturing batches. It generally evens out as the roof weathers over the first season.
• Some granule loss in the gutters right after installation. New shingles shed a small amount of loose surface granule in the first weeks. Ongoing, heavy granule loss later on is the thing to watch for, not a light dusting now.
• A bit of tar at intentional, appropriate points. Sealant used correctly, in small amounts, at specific spots like nail heads on a low-slope section or around a boot, is normal. The red flag is tar used as the entire flashing method along a wall or chimney, not a dab used correctly.
• Minor waviness over an older plank deck. Houses with original wood plank decking instead of plywood sometimes show a slight undulation that has nothing to do with the new roof and everything to do with lumber that has been up there for decades. That is a deck characteristic, not a new-roof defect.

What to do if something is wrong

Raise it before final payment, in writing, with photographs. Ask for a specific remedy and a specific date. A good contractor will want to know. That is not a courtesy line, it is the honest incentive: a crew that stands behind its work would rather fix a missed detail this week than find out about it from a leak or a bad review six months from now.

Questions homeowners ask us about this