Waterproofing 101 for Property Managers: Stop Leaks Before They Become Claims
Water intrusion is one of the most common (and expensive) problems in commercial properties. The tricky part is that the visible leak is rarely the real source. Water travels—sometimes far—before it shows up as a stain, bubbling paint, or a tenant complaint.
For property managers, the goal isn’t just stopping today’s leak. It’s preventing repeat issues, protecting the structure, and reducing disruption.
What “waterproofing” actually means
Waterproofing is a system that keeps water out of the building assembly—not just a surface patch.
Depending on the area, waterproofing can include:
Deck and balcony waterproofing
Traffic coating systems on elevated slabs
Sealants at transitions and penetrations
Crack and joint sealing
Drainage corrections (so water moves away instead of pooling)
Building envelope repairs (where walls meet roofs, windows, and decks)
Why small leaks become big claims
A “minor” leak can quickly turn into:
Interior damage (drywall, flooring, finishes)
Mold risk and air quality complaints
Concrete deterioration (spalling, delamination)
Corrosion of embedded steel and connectors
Slip hazards and tenant safety issues
Repeat callbacks and emergency mobilizations
The earlier you catch it, the cheaper it is to fix.
Early warning signs PMs should take seriously
Common red flags that usually show up before a major failure:
Water staining on ceilings or walls
Bubbling/peeling paint or soft drywall
Efflorescence (white, chalky deposits on concrete/masonry)
Musty odors in corners or near exterior walls
Cracks at slab edges, transitions, or around penetrations
Ponding water on decks or walkways
Failed sealant at joints, curbs, and terminations
Rust staining (often a sign water is reaching steel)
If you’re seeing two or more of these in the same area, it’s usually time for an inspection—not another patch.
The most common leak locations (where to look first)
In commercial properties, leaks often start at:
Deck-to-wall transitions
Parapet caps and terminations
Expansion joints
Window perimeters and flashing details
Planters and poorly drained areas
Penetrations (pipes, conduits, anchors)
Stair landings and elevated walkways
These are movement zones and detail-heavy areas—exactly where quick fixes fail.
Patch vs. proper repair: how to decide
A patch might be appropriate when:
The issue is isolated and clearly identified
The surrounding system is in good condition
The repair is part of a short-term plan before a scheduled recoat
A full waterproofing scope is usually needed when:
Leaks are recurring
Multiple areas are showing symptoms
The coating/membrane is aged or brittle
There’s concrete damage (spalling/delamination)
The building has high foot/vehicle traffic on elevated slabs
What a professional waterproofing scope should include
A commercial-grade waterproofing scope typically includes:
Assessment of the full water path (not just the drip point)
Moisture intrusion diagnosis and documentation
Surface prep (cleaning, grinding, removal of failed materials)
Crack/joint treatment and transition detailing
Correct system selection for traffic level and exposure
Final inspection and maintenance recommendations
Preventative maintenance: the easiest win
If you manage multiple buildings, a simple routine helps prevent emergencies:
Inspect before and after the wet season
Photograph problem areas and track changes over time
Address sealant failures early (joints and transitions)
Plan recoats before the system reaches end-of-life
Preventative work is almost always cheaper than emergency response and interior repairs.
Request an inspection / Request a bid (CTA)
Exteriors Doctor provides commercial waterproofing, building envelope repairs, expansion joint systems, concrete repairs, and structural rehabilitation throughout Snohomish and King Counties.
Request an inspection: (425) 405-0027
Request a bid: https://www.exteriorsdoctor.com
