Consider testing when any of the following apply: You can’t find the source (hidden leaks/attic/inside walls) but occupants have symptoms — targeted testing can help locate hidden contamination. Legal/insurance/real-estate reasons — to document conditions before/after...
Fast overview — the three most reliable tests
In-situ RH probes (ASTM F2170) — best for concrete slabs; measures internal relative humidity. Calcium-chloride MVER (ASTM F1869) — measures moisture vapor emission rate from the slab surface (useful for adhesives/finish acceptance). Moisture meters (pin and pinless)...
What inspectors check (quick list)
Visual signs: stains, efflorescence, blistering paint, soft or spongy materials, mold/mildew odors. Non-invasive scans: infrared/thermal imaging to spot temperature anomalies that often indicate moisture behind surfaces. Moisture meters: pinless (surface/near-surface)...
Who’s commonly responsible
Tenant — if the leak comes from something they installed or caused (appliance hookup, clogged drains, negligence). Unit owner / homeowner — if the leak originates inside their unit/house (internal plumbing, water heater inside the unit). Neighbor / adjacent unit owner...
How to detect water intrusion — signs, tools, and what to do next
Water intrusion starts small and often hides where you least expect it. Catching it early saves money, prevents mold, and avoids structural damage. Below is a straightforward, step-by-step guide showing how to detect water intrusion in homes, condos, and commercial...
What is a water intrusion inspection?
A water intrusion inspection is a focused, systematic evaluation of a building’s exterior envelope and assemblies to find where unwanted water is entering, how it’s traveling through the structure, and how much damage or moisture has accumulated. It’s about diagnosing...
What does a moisture map look like? — A clear, visual guide for Los Angeles property owners
When a building is wet where you can’t see it, a moisture map turns mystery into a clear plan. Exterior Systems Construction—who provide water intrusion testing and moisture-mapping services for Los Angeles HOAs, property managers, and homeowners—uses moisture maps as...
What does moisture mapping mean? — A practical guide for property owners in Los Angeles
Hidden moisture is one of the stealthiest problems a building can have: it weakens structure, feeds mold, and often lives behind perfectly fine-looking walls. Moisture mapping is the diagnostic process professionals use to find, measure, and document exactly where...
What’s the best way to find a leak in your roof? (A practical guide for Los Angeles property owners)
A leaking roof is one of those problems that starts small and gets expensive fast. The single best principle for finding a roof leak is: start inside, trace the water, then confirm outside — and call a trained water-intrusion pro when the source is unclear. Below is a...
Does home insurance cover leak detection?
Insurance typically covers sudden & accidental water loss (pipe bursts, appliance failures). If that kind of event causes damage, the insurer often pays to repair the damage (subject to your deductible and limits). Allstate Insurers usually do not cover damage...