TL;DR
A box gutter liner is the continuous waterproof membrane or metal pan fabricated to fit inside a built-in gutter, the rectangular trough concealed within the roof edge or cornice of many older and historic homes. Because a built-in gutter sits over living space rather than hanging off the fascia, a leak rots cornice framing and pours into walls, so the lining is the system's working surface.
What it means
A box gutter liner is the continuous waterproof membrane or metal pan fabricated to fit inside a built-in gutter, the rectangular trough concealed within the roof edge or cornice of many older and historic homes. Because a built-in gutter sits over living space rather than hanging off the fascia, a leak rots cornice framing and pours into walls, so the lining is the system's working surface. Traditional materials are soldered copper, terne, or stainless steel; EPDM and reinforced PVC retrofits cost less but complicate future repairs. Replacement requires correct slope to the outlets and expansion joints on long runs, and the metal gauge and seam method belong in any restoration quote.
Where it sits in the glossary
Box gutter liner is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
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