The physical barrier between the interior and exterior of a building, including the roof, exterior walls, windows, doors, foundation, and waterproofing systems. Building envelope maintenance protects against water intrusion and energy loss, and some costs may appear in CAM.
The building envelope encompasses all components that separate conditioned interior space from the exterior environment: roofing membranes, exterior wall assemblies (curtain wall, masonry, EIFS), window systems, weatherproofing, caulking and sealants, vapor barriers, and foundation waterproofing. Routine maintenance (caulking, sealant replacement, minor leak repairs) may be CAM-eligible depending on lease language. Major repairs and replacements (re-roofing, curtain wall replacement, exterior re-cladding) are structural or capital in nature and are typically excluded from CAM.
A landlord included a $420,000 exterior re-cladding project in CAM as "building envelope maintenance." The re-cladding was a structural capital improvement that benefited the building's value for 30+ years. By labeling it as maintenance, the landlord shifted the full cost to tenants in a single year.
Most leases exclude structural repairs from CAM. If you see a large "building envelope" or "exterior maintenance" charge, request detailed invoices. Caulking and minor sealant work are maintenance, but re-roofing, wall replacement, and waterproofing membrane installation are capital projects that should not appear in your CAM reconciliation.
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Find My OverchargesThis page provides general educational information. It is not legal advice and may not reflect the most current law in your state. Consult a licensed attorney for advice specific to your situation.
