Spaced Decking & Knee-Wall Attics: Why Older Twin Cities Roofs Need Extra Work

If you own an older Saint Paul or Minneapolis home, your roof may need more than shingles.

Three Rivers Contracting · Twin Cities

Spaced (plank) decking

Older homes were often sheathed with spaced boards — fine for old wood shingles, but the gaps leave modern nails with nothing to bite and let ice & water shield sag. We overlay or replace it with solid plywood/OSB so your roof has a continuous, code-compliant nailing surface (and a valid manufacturer warranty).

Knee-wall attics

One-and-a-half-story and Cape Cod homes — common in Armatage, Kenny, Diamond Lake, Nokomis, and Powderhorn — have short knee walls along sloped ceilings that create cramped, hard-to-vent attic pockets. Done wrong they leak heat at the eaves and drive ice dams.

How we fix it

• Air-seal the ceiling plane and block the joist bays under the knee wall.
• Add rigid-foam blocking and rafter baffles so air still runs soffit-to-ridge.
• Insulate to keep the eaves cold and the living space comfortable.

It’s the difference between a roof that fights Minnesota winter and one that sheds it.