What are the most common entry points for water in commercial buildings?

Water intrusion in commercial buildings is most frequently observed at locations where exterior materials transition or where protective layers are compromised. Common entry points include:

• Joints and sealants: Failed or deteriorated sealants at expansion joints, control joints, and around windows or doors allow water to penetrate building envelopes. This is especially problematic in New England, where significant temperature swings and freeze-thaw cycles cause joints to expand and contract, accelerating wear.

• Masonry cracks and mortar joints: Cracking in brick, block, or stone masonry, as well as deteriorated mortar joints, can provide direct pathways for water. Older masonry can be particularly susceptible to weathering from wind-driven rain, ice, and moisture infiltration.

• Roof and parapet details: Poorly maintained flashing, deteriorated parapet walls, or open seams at roof perimeters are common culprits. Water can migrate from the roof edge into wall assemblies if flashing is compromised, leading to hidden concerns inside the building.

• Window and door perimeters: Improperly installed or aged window and door systems may lack adequate sealants, flashings, or sills, allowing moisture intrusion during storms or snow melt events.

• Flashing, copings, and sills: Missing, corroded, or poorly detailed metal flashings, window sills, and parapet copings fail to channel water away from vertical surfaces, increasing the risk of leaks, especially during seasonal freeze-thaw events.

• Below-grade walls and foundations: Water intrusion at foundation walls, below-grade parking garages, areaways, or basement entries often results from failed waterproofing membranes, improper drainage, or cracks. In New England, the combination of salt exposure, groundwater, and seasonal snowmelt intensifies this risk.

• Mechanical penetrations and utility entries: HVAC, plumbing, electrical, and other utility penetrations are frequent weak points if not properly sealed and maintained according to commercial enclosure standards.

Proactive inspection, timely repairs, and planned preventative maintenance are essential to preserving the long-term structural and operational integrity of commercial buildings. Building age, construction type, historic status, and local weather patterns all impact the most vulnerable points. Professional evaluation is recommended to pinpoint specific risks and prioritize repairs for long-term performance and asset value.