Why do barn and shop roofs get less attention than house roofs?
Because nobody lives under them, so leaks go unnoticed until stored goods are damaged. A small drip on a barn floor doesn't show up as a ceiling stain. Check outbuilding roofs when you check the house, preferably before the wet season, and look inside for light and rust.
A barn that has leaked for years usually has damage in the framing, the hay and the equipment below. Walk the building on a bright day and look up for pinholes of light. Each is a place water gets in.
Why does my shop roof drip on cold mornings?
Condensation. Warm, moist air inside a heated or occupied building meets the cold underside of the metal and turns to water. It looks like a leak but there is no hole. A condensation barrier, insulation or ventilation solves it. Resealing the roof will not.
The fix is to keep the metal from being cold against warm air. A roofer or builder can advise on a spray-applied barrier, rigid insulation or proper ridge and eave ventilation. See attic ventilation for the principle.
Does an outbuilding roof need a permit?
It might. Rules depend on the county or city, the size and use of the building, and whether the work is repair or replacement. Skagit, Snohomish and Whatcom counties each apply their own. Ask the building department before work begins and put the answer in the written scope.
Agricultural buildings are sometimes treated differently from houses. This site cannot say how, so ask the office that covers your address. The permit guide lists what to ask.
How should you plan a barn roof job around animals, hay and weather?
Pick a dry stretch, move or cover hay and equipment, keep livestock clear of the work and the debris zone, and ask the roofer how the building will be closed in each evening. Plan for a day or two of slack for weather, and confirm the delivery route for long panels.
Roofing over stored hay is the sharpest risk. A roof opened in the morning and not closed by dark can be rained on overnight. A sensible plan strips and covers in sections, so no part of the building is left open.
Agree on where the crew parks, where discarded panels go and who closes gates. In open country, a loose animal or a stray screw in a pasture is a real cost, and small arrangements made in advance prevent it.
How do you choose between repairing and re-roofing an old barn?
Check the condition of the panels, the fasteners, the purlins and the ridge. If the metal is sound and the screws are the problem, re-fastening and resealing can add years. If panels are rusted through, framing is rotten or the roof sags, replacement is the better value. A roofer can show you which applies.
Barns are often kept going on small repairs for decades, and each patch has a story. A roofer can read it. Many leaks come from a few failed fasteners or a split ridge cap, and an afternoon of work can end them.
On the other hand, a roof that has been held together with sealant and tar for years may have rot in the purlins below. Ask the roofer to look inside as well as outside, and to say what they would do if they found a damaged framing member.
