How Home Inspectors Use Their Nose to Sniff Out Trouble in a Home

As we discussed in last week’s blog post about how home inspectors employ their sense of hearing to discover potential problems in a home, today we’ll be exploring an inspector’s use of their olfactory system, or “sense of smell,” to determine if odors found during a comprehensive roof-to-foundation inspection are cause for concern or not.

It is important to note that due to the non-invasive nature of home inspections, pinpointing the exact source of an odor (behind a wall or defective appliance part, for example) may not always be possible. Here is a brief checklist of smells and related issues that the home inspectors at A-Pro Home Inspection have sniffed out over the last 27 years.

Heating System: When operating the heating system—especially an older one—your inspector may discover troubling smells coming from the equipment, including the odor of burning metal or wires (a possible fire hazard), chemicals, or rotten eggs, indicating a possible gas leak. Further, smells coming from the duct system can be attributed to a number of factors, such as a dead rat or mouse rotting in the ductwork (ammonia-like smell), animal droppings, heating combustion flue gasses, mold, or sewer gasses that have made their way into the duct system. When running appliances, your inspector may detect the burning smell of an overheating electric motor. Some sources of smells can be easily and cheaply remedied, such replacing an HVAC system’s dirty air filter.

Other smells that will draw the attention of your inspector include smoky smells coming from ductwork, which may be an indication of an obstructed or blocked chimney; strong burnt fuel odors—a possible sign of issues with the furnace’s burners; and a dusty smell that doesn’t go away after the system is initially activated for the season.

Mold: One of the most common smells detected during a home inspection is the earthy, musty odor of mold, often described as the essence of wet socks. The presence of this pungent smell will be a red flag for inspectors, who will look for and report on signs of mold growth in damp areas throughout the home, including bathrooms, basements, kitchens, windows and sills, flooring, attics, garages, crawlspaces, and other locations. For an in-depth analysis, many A-Pro inspectors are certified to perform more advanced mold inspections that involve taking samples and having them tested in a laboratory, with recommendations for remediation steps based on the findings.

Plumbing: Sewer gasses released in a home can be more than merely unpleasant—they may pose a serious threat as well. Your inspector will note smells coming from water traps and sinks. Possible culprits may be missing or broken clean-out plugs, which are designed to prevent sewer gasses from coming inside from the main line or house traps; a poorly sealed toilet; and sewer line leaks (your inspector may also identify toilet gurgling and slow drainage coupled with the offensive smells). Other potential causes, such as loose connections along a vent pipe or sewer line, may be hidden from view. Even if the cause isn’t clear, these smells will be highlighted in the home inspection report. To get a complete picture of whether the smell inside is due to blockage of the main sewer line, A-Pro can perform a video Sewer Scope Inspection to get an up close look at internal pipe damage and obstructions from tree roots. This service is not included in the regular 500-point home inspection.

Electrical: A strong plastic burning smell in a home could be a sign of melting sheathing covering electrical wires. This situation poses a serious fire hazard and may warrant immediate action. Sometimes electrical-related smells will take the form of urine, fishy, or sulfur-like odors, which may be detected near outlets, switches, or behind walls.

Carbon Monoxide: Yes, dangerous carbon monoxide is an odorless gas, but your inspector may smell other signs pointing to carbon monoxide issues, such as combustion smells related to the failure of the heating system to properly vent gasses to the outside. While we’re on the subject of odorless gasses, we don’t want to miss the opportunity to remind you of the importance of having your home inspected for cancer-causing radon—another extra service offered from A-Pro Home Inspection.

Other odor-related issues include a burning smell from a built-in dryer—a possible indication of a clogged dryer vent; burning smells when an air conditioner kicks in; musty, rotten smells from the AC system, which may be a telltale sign that there is damage to its drainage system; and musty, damp smells from the dishwasher, possibly resulting from a kinked hose or clogged drain, among other causes.

Reporting on smells in a home is part of A-Pro’s 500-point home inspection. Ask your local A-Pro Home Inspection team about its complete foundation-to-roof inspection in Boulder. To schedule one, call 1-720-438-4595 or visit the link below.