A careful home walk-through can help you find visible leaks, damp materials and maintenance problems. This Father’s Day, make a record of what needs repair and what needs qualified assessment.
A user-level inspection is limited to accessible observations. It cannot rule out hidden mold, certify health or safety, or replace electrical, structural or medical evaluation.
What You'll Need
Gather these supplies before starting:
- Powerful flashlight (bright LED recommended)
- Flashlight for accessible areas; do not remove electrical or wall panels to search for mold.
- Moisture meter (optional; choose one suited to the material and the question you are investigating)
- Hygrometer (humidity meter)
- Phone or camera for documentation
- Notebook and pen
- If cleanup is needed, assess whether it is suitable for you and use the required protection; a respirator does not make an unsafe inspection area safe.
- View attic access only from a safe, stable location; leave entry to a qualified person if footing, wiring or contamination is uncertain.
- Old clothes you can wash immediately after
The Inspection Process
Start with the Nose Test
A musty odor is a clue to investigate moisture and materials, not a reliable mold detector:
- Walk slowly through each room
- Pay attention to earthy, musty odors
- Note where odors are strongest
- Record persistent odors, including those dismissed as an old-house smell; several building conditions can cause odors.
Check Humidity Levels
Take hygrometer readings throughout the house:
- EPA recommends indoor humidity below 60%, ideally 30–50%; compare repeated readings with actual condensation and damp materials.
- Check basement, bathrooms, and any suspicious areas
- Note significant variations between rooms
- Repeated high readings call for source and ventilation checks; one reading does not diagnose hidden moisture or mold.
Room-by-Room Inspection
Basement
If the home has a basement, start with accessible drainage, stored items and known leak locations:
- Check walls for water stains or white powdery deposits (efflorescence)
- Look for water intrusion at floor/wall joint
- Inspect behind stored items
- Check around windows and window wells
- Test sump pump operation
- Examine HVAC equipment and ductwork
- Look at water heater area
- Check any finished areas for soft spots in drywall
Bathrooms
Moisture makes bathrooms mold-prone:
- Inspect caulk around tub, shower, toilet
- Check under sinks
- Look at ceiling for staining
- Examine grout for deterioration
- Check behind toilet
- Test exhaust fan operation
- Look for mold around faucets and fixtures
Kitchen
- Visible sink plumbing and the cabinet floor
- Accessible floor and supply connections near the refrigerator; do not pull it out unless safe and permitted
- Visible dishwasher edges and nearby flooring without disconnecting the appliance
- Around ice maker lines
- Range hood and exhaust area
- Window sills above sink
Bedrooms
Do not overlook sleeping areas:
- Window frames and sills
- Behind headboards on exterior walls
- In closets, especially exterior wall closets
- Corners of rooms near exterior
- Around any AC units
Attic
Inspect only from safe access. Do not walk on ceiling framing or insulation or enter around exposed wiring, structural damage or suspected extensive mold.
- Check roof sheathing for dark staining
- Look for daylight through roof (leak paths)
- Inspect around all penetrations (vents, chimney)
- Check insulation for dampness
- Verify bathroom vents exhaust outside, not into attic
- Look for signs of pest intrusion
Crawlspace
If your home has a crawlspace, assess access from outside first. Do not enter standing water, confined or poorly ventilated areas, exposed wiring, sewage or suspected extensive mold.
- Check for standing water
- Inspect vapor barrier condition
- Look at subfloor and joists
- Check for pest damage
- Note any odors
Using a Moisture Meter
A moisture meter gives material-dependent readings that can help compare locations. It does not identify mold or prove that a wall cavity is dry.
How to Use
- Use the meter’s specified mode and material setting. Do not insert pins where concealed wiring, plumbing or other hazards may be present.
- Compare readings to dry reference
- Interpret readings using the instrument instructions and a comparable unaffected reference; some materials, metals or salts can affect results.
- Check suspicious areas and compare to normal areas
What Readings Mean
- Wood: interpret the meter’s moisture-content scale for the species, material, conditions and intended repair; avoid a universal pass/fail cutoff.
- Drywall: many meters show a relative scale rather than a true percentage. Do not apply a universal 1% threshold.
- Always compare wet to dry areas
Documenting Your Findings
Thorough documentation helps track issues:
- Photo everything suspicious
- Note location and size of any findings
- Record humidity and moisture readings
- Date your documentation
- Create a map of problem areas
What You Might Find
Observations That Need Investigation
- Visible fuzzy or discolored growth
- Musty odors
- Record symptoms for a healthcare professional; symptoms in a room do not identify active mold.
- Discoloration on surfaces
Signs of Moisture Problems
- Water stains
- Peeling paint or wallpaper
- Warped or buckled materials
- Efflorescence on concrete
- Condensation on surfaces
Signs of Past Water Damage
- Old stains
- Repaired areas
- Mismatched materials
What to Do with Findings
Minor Issues
A small cleanable patch may be suitable for DIY cleanup when its water source is understood, access is safe and health or contamination concerns do not change the plan:
- Document visible growth and moisture clues
- For a small, cleanable hard-surface area, use a product labeled for that material and follow the label
- Do not mix cleaning products; use the ventilation and protective equipment required by the label
- Address the moisture source and monitor for recurrence
Significant Findings
Call professionals for:
- Large mold areas (over 10 sq ft)
- Mold in HVAC system
- Hidden mold behind walls
- Ongoing water intrusion
- Health symptoms need clinical advice; arrange a building assessment separately when there is an unresolved moisture question.
Our DIY vs. Pro tool can help you decide the right approach for what you find.
Make It a Routine
One inspection is good; regular inspections are better. Consider:
- Quarterly quick inspections (high-risk areas)
- Annual comprehensive inspection
- Post-storm checks
- Seasonal transitions (spring thaw, pre-winter)
The Dad's Satisfaction
The useful result of a walk-through is a dated list of visible conditions, repairs and inaccessible areas. Recheck known trouble spots after weather or maintenance, and bring unresolved questions to the right professional.
Sources and Further Reading
For current sampling guidance, see EPA's Is Sampling/Testing for Mold Necessary?.