Detached garage and shop roofs around Vancouver, WA

Detached garages and shops often get roofed with whatever was cheapest at the time and then forgotten. Many have no gutters, no ventilation and no underlayment. Older garages may still have rolled roofing or a worn three-tab shingle. Pole buildings on acreage usually have exposed-fastener metal over purlins with no deck at all. Each of those setups has different weak points, and each calls for a different plan when it starts to leak.

Our crews roof and repair detached garages, workshops, pole barns, hobby shops, carports and small storage buildings. We install composite shingles to match the house, metal panels for shops and barns, and low-slope membranes for flatter garage roofs. Because these buildings often hold tools, equipment and vehicles, we also look at condensation and ventilation, which cause as much damage inside a shop as roof leaks do.

Common problems on garage and shop roofs

Outbuildings tend to be built lighter than houses. We often find undersized rafters, sagging ridges, and decking made of old boards or thin sheathing that flexes underfoot. On metal shop roofs, the screws and washers age out and leak at hundreds of points at once. On older garages, rolled roofing cracks and peels at the seams, and the lack of gutters means rain splashes the walls and rots the bottom plates and door frames.

Condensation is the other big issue. A shop with a bare metal roof and no insulation can drip on the floor on cold, damp mornings even with no leak at all. Tools rust, stored boxes mold, and owners assume the roof is failing. We separate the two problems by checking the panels from above and the underside from inside, then propose the fix that actually matches what is happening, whether that is sealant, a barrier or venting.

Garage and shop roofing options

Materials for outbuildings come down to framing, budget and how the building is used. A garage next to the house usually looks best matched to the house roof. A shop out on acreage may be better served by metal, which sheds needles and snow well. Flat garage roofs that double as a deck or patio need a membrane designed for foot traffic. We price the options that fit your building and explain the tradeoffs.

• Composite shingles to match the main house
• Exposed-fastener metal panels over purlins
• Standing seam metal for finished shops
• Condensation barriers under metal panels
• Low-slope membranes for flat garage roofs
• New gutters, vents and skylight panels

Framing checks before a new roof

Before we put new roofing on any outbuilding, we look at the structure underneath it. Sagging ridges, cracked rafters and rotted purlins need repair first, or the new roof will ripple and leak at the low points. On pole buildings we check the purlin spacing against what the new metal panels require. On garages with board decking we usually add new sheathing so shingles have a solid surface to nail into and do not crack.

Some owners also want to change how the building is used, such as turning a garage into a heated workshop or a studio. That can change what the roof needs: more insulation, better ventilation, or a vapor barrier under the metal. Telling us the plans for the building early lets us build the roof once instead of tearing into it again later. A finished, heated shop also needs proper intake and exhaust venting.

Repair or re-roof an outbuilding

Small leaks on a garage or shop roof can usually be repaired: a few failed screws, a cracked pipe flashing or a torn piece of rolled roofing. When an old metal roof is leaking at many fasteners, a full screw replacement often gives it more life at a fraction of the cost of new panels. When the roofing has failed across the whole building, or the decking is soft, a re-roof is the better choice. We show photos so you can see the condition yourself.