Pole Barn Roof Leaking at Screws — Fasteners Replaced, Laps Sealed
Drips on the floor under the barn roof in a row, rust streaks from the screw heads, nails backed out of the ribs. The steel is fine; the fasteners are done.
When a pole barn roof is leaking at screws or nails, JMB Builders pulls the failed fasteners and replaces them with new gasketed screws, upsized where the holes are stretched or stripped, and reseals the side laps, end laps and ridge. Older barns with ring-shank nails get every nail replaced with screws. North metro and central Minnesota, priced per project, with a repair versus re-sheet call from photos.
- Priced per project, by roof area
- Nails and failed screws replaced
- Upsized screws for stretched holes
- Laps and ridge resealed
- Licensed MN contractor BC809005
Exposed-fastener steel roofs leak at the fasteners first. The rubber washers on the screws dry out and crack in the sun, screws driven too tight crushed their washers on day one, screws driven crooked never sealed, and heat and cold work every screw loose a little each year. Older barns were often nailed with ring-shank nails, which back out as the steel moves and lift the washers off the steel.
The fix is fastener by fastener. Nails are pulled and replaced with screws. Screws with cracked or crushed washers come out and new gasketed screws go in; where the hole in the steel or the purlin is stretched, the replacement is a size up so it bites fresh wood. Every screw is driven square and snug, not crushed. Side laps, end laps, ridge cap and trim get new sealant or closures where they are open.
It stops being worth it when the steel itself is rusted through at the laps, badly hail-dented, or the purlins under it are rotted. Then new steel is the better money, and we say so from the photos.
What you supply
- Photos of the roof from a ladder or a drone, and of drip spots or stains inside
- The building size and roughly how old the roof is
- Whether it is nailed or screwed, if you know
- Clear floor under the drip spots, or tarps over equipment, on work day
What JMB supplies
- Removal of old nails and failed screws
- New gasketed screws in the steel's color, upsized where holes are stretched
- Sealant at side laps and end laps where they are open
- Ridge cap and trim refastened, with closures replaced where missing
- A check of the purlins and steel from inside while we work
- Fall protection and photos of the roof in your job folder
How it is priced: per project
Quoted in writing from your photos within one business day. What moves the number:
- Roof area and number of fasteners to replace
- All fasteners replaced versus only the failed ones
- Roof pitch and height, and access for a lift
- Laps and ridge that need resealing
- Purlins found rotted or loose from inside
- Rusted or damaged steel sheets that need replacing in spots
Tell us whether it leaks everywhere or in a few rows. A photo of one screw head up close shows whether the washers are the problem.
How long it takes
Most pole barn roofs: one to two days. Larger roofs or a full nail-to-screw swap: two to four days.
How your project works
- 1
Send photos, get a written quote
Send three photos of the space and a sentence about what you want. You get a clear, itemized quote within one business day. We only come out to measure first when the job needs a tape measure — no pressure, no games.
- 2
Pick materials, or bring your own
We help you choose profiles and materials that fit the house and the budget, or match your existing millwork exactly — or you buy the door or trim yourself and we install it. Everything is confirmed before the crew is scheduled.
- 3
Clean, precise installation
The crew shows up on time, protects floors and furniture, and installs with tight joints and consistent reveals. Photos of the finished work go in your job folder.
- 4
Walkthrough and invoice
We walk the finished work with you. If anything is not right, we fix it before we call the job done. Then one invoice, paid by check or direct deposit — no card fees, no payment links.
Pole Barn Roof Leaking at Screws — Fasteners Replaced, Laps Sealed: questions, answered
Why is my pole barn roof leaking at the screws?
The rubber washers under the screw heads dry out and crack, screws driven too tight crush their washers, crooked screws never seal, and the steel's movement loosens them over the years. The water comes in around the shank and drips in a line along the purlin.
Should I replace nails with screws on a metal barn roof?
Yes. Nails back out as the steel expands and contracts, lifting their washers off the steel and letting water in. Screws hold the steel down tight and keep the washer sealed. Every nail is pulled and a gasketed screw goes in, a size up where the nail hole is stretched.
Can I just put sealant over leaking metal roof screws?
Sealant or a coating over the screw heads buys a season or two, then cracks with the steel's movement. New gasketed screws seal the hole the way it was designed. Sealant belongs at laps and trim, not as a fix for failed fasteners.
What size screw do I use if the old hole is stripped?
A size larger in diameter, so the threads bite fresh wood in the purlin and the washer covers the stretched hole in the steel. Where the purlin itself is split or rotted, the screw goes into a new spot or the purlin is repaired first.
Should I replace all the screws on my pole barn roof or just the leaking ones?
On an older roof where the washers are cracked everywhere, replace them all; the ones not leaking today will be next year. On a newer roof with a few bad screws from install, replacing only the failed ones is fine. A close photo of several screw heads tells us which.
When should a pole barn roof be re-sheeted instead of rescrewed?
When the steel is rusted through at the laps or the bottom edge, badly hail-dented, or the purlins are rotted. New fasteners do not fix rusted steel. At that point new steel over checked purlins is the better money.
Recent JMB work, from our job log
59 installs recorded across 30 Twin Cities communities since Dec 2025. Window and door installs for homeowners and for the builders and dealers we sub for. Counts come straight from our job log; no customer names.
Get a written quote for this job
Three photos and a sentence is enough. You hear back within one business day. Or text the photos to 763-204-2099.
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Read morePage reviewed September 26, 2026 · JMB Builders LLC, MN license BC809005 · All pole barns pages
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