Walls

In the Structure category, we considered the walls as it relates to their stability and load-bearing capacities. In this section we are inspecting the walls’ finish coverings. While we focus on conditions that seem more “cosmetic”, we must consider whether changes or damage in a wall covering also imply an ongoing or potential structural issue with the wall itself. Why is that crack there? Is this a load-bearing wall, or is it a wall dropping away from the bearing wall? Is there a water penetration issue present?

Inspect for cracks, damage, separations, loose areas, and stains. Loose plaster can be a hazard. Remember that walls separating a garage from the living spaces should be fire-rated and intact.  Always perform an Infrared scan on the interior surfaces, and follow-up any anomalies with your moisture meter. Water penetration can cause significant damage and expense, and has structural implications.

The interior wall is damaged. Repair or replace the wall.

The interior wall is water damaged. Testing with a moisture meter indicates low moisture content (dry) at the time of this inspection. Hire a contractor for an evaluation and to make repairs as needed.

The interior wall is water stained or damaged. Testing with a moisture meter indicates high moisture content at the time of this inspection. There may be hidden damage. Hire a contractor for an evaluation and to make repairs as needed.


Infrared thermal imaging shows an area in the interior wall with likely water penetration. Testing with a moisture meter indicates high moisture content at the time of this inspection. There may be hidden damage. See the supplied infrared images. Hire a contractor for an evaluation and to make repairs as needed.


Infrared thermal imaging shows an inaccessible area in the interior wall with likely water penetration. Confirmation with a moisture meter for high moisture content is not possible. There may be hidden damage. See the supplied infrared images. Hire a contractor for an evaluation and to make repairs as needed.


There is a breach (hole, damage or opening) in the fire-rated wall. This is a safety concern. Replace the portions of the wall with fire-rated material.

The wall separating the garage from the adjacent living area is not fire-rated. This is a safety concern. Replace the wall with fire-rated materials.

There is cracking at the interior wall that is larger than what would be expected with typical settlement. This may be a structural issue. Hire a contractor for an evaluation and to make repairs as needed.

There are gaps in the tile wall. This will allow water penetration and deterioration. Repair the wall.

There are missing tiles in the wall. This will allow water penetration and deterioration. Repair the wall.

There are cracked tiles in the wall. This will allow water penetration and deterioration, and will cause the tiles to become loose. Repair the wall.

The wall tiles are loose or damaged. Loose tiles are apparent by lightly tapping the surface. This reveals tiles that are not properly bonded and will move, have grout breakage, crack, and come off. Repair the wall.

The tile wall is damaged. This will allow water penetration and further deterioration. Repair or replace the tiles.

The wall paneling is loose. This may allow it to come off completely. Repair the paneling.

The wall paneling is damaged. Repair or replace the paneling.

The wall paneling is missing. Replace the paneling as needed.

The wall paneling is warped. This indicates excess humidity or water penetration in the area. Hire a contractor for an evaluation and repairs as needed.

Infrared thermal imaging shows an area in the interior wall paneling with likely water penetration. Testing with a moisture meter indicates high moisture content at the time of this inspection. There may be hidden damage. See the supplied infrared images. Hire a contractor for an evaluation and to make repairs as needed.

An infrared camera DOES NOT “see” or measure moisture. All it does is show differences in surface temperatures. This has a significant effect on correct image interpretation when working in cold weather.


Evaporative Cooling vs. Thermal Capacity

Evaporative cooling and water’s high thermal capacity are the two reasons we can use infrared to detect possible moisture.


Thermal Capacity

Water’s high thermal capacity, or ability to absorb heat energy, comes into play when moisture is “trapped.” In our work this occurs primarily under roofing membranes, e.g. modified bitumen, EPDM, etc. We normally do not perform roofing membrane inspections as a part of a Home Inspection; we work from the interior of the house.


Evaporative Cooling

Evaporative cooling is the main thermodynamic mechanism that we rely upon to detect possible moisture. This occurs in a “open” system. While we think of a wall or ceiling area as somewhat sealed, they are sufficiently open to allow air and vapor flow.

In order for water to change state from a liquid to a vapor, heat must be added. That heat is drawn from the surrounding materials, e.g., the insulation, framing, drywall, etc. Infrared allows us to see the temperature drop when heat is removed from the building materials to fuel the water’s state change.

Everything looks good. The outside grade is just below the window:

The hose faucet in the corner is leaking. Heat is drawn away from the wall materials and carpet as the water changes state:


Why does cold weather matter?

First of all, this concerns infrared imaging of exterior walls and ceilings. By exterior, we mean that the other side of the surface is an unconditioned area. This applies to a ceiling below an unconditioned attic as well as a home’s actual “exterior” wall structure. This does not apply to fully interior walls, or to ceilings below conditioned areas, i.e. the 1st. floor ceiling in a 2-story house.

Cold weather matters because, as noted, we rely primarily on evaporative cooling to detect possible moisture. Simply put, water has a hard time changing from a liquid to a vapor when it’s 45°F outside. True, some heat conducts into the wall cavity in a heated house. But the colder it is outside, the harder evaporative cooling becomes. In the Winter cold spots are much more likely to indicate an insulation anomaly.


Confirm suspected moisture with your meter whenever possible!


Visible light image in Winter:

IR image: why would moisture flow downwards like this? Confirm with your moisture meter; it’s an insulation anomaly!

Winter IR image: the kneewall isn’t insulated, and it’s too cold for evaporative cooling. Use your moisture meter.

Look at the temperatures! Why would water flow this way? Use your moisture meter.