The interior walls may be made of: drywall (Sheetrock); lath and plaster; wood paneling or planks; exterior siding materials; logs and masonry products including brick, concrete, concrete blocks or adobe.
Each material has its own unique characteristics, but our primary concerns are cracks, holes, stains, deterioration, deflection and the presence of mold or mildew.
Walls always have a story to tell. They may seem to be just flat surfaces but they can be the first indicators of larger structural problems. The primary indicators are cracks so we begin our inspection by looking for the obvious.
In drywall material there are basically two kinds of cracks; settlement (or shrinkage) cracks and stress cracks.
The difference between a settlement (or shrinkage) crack and a stress crack.
Settlement cracks are those cracks that may be caused by the settlement of a new home into what we call its “foot print” which is the drying of the green wood of the building's framing.
Temperature and humidity variations can change the shape and size of a building during different seasons and can contribute to the appearance and reappearance of settlement cracks.
Settlement or shrinkage cracks are usually straight and run along the joints where two pieces of drywall (Sheetrock) butt up against each other. The crack is actually in the mud and tape between the two pieces of drywall. The tape and mud have split open slightly due to movement in the wall.
The tape and mud compounds under the texture are not strong enough to hold the joint together as the wall moves or “settles.”
Such cracks are usually incidental in their size or width but can be annoying in their appearance. Some people will try many different ways of hiding or eliminating them and usually the more they try the worse the cracks look.
Many factors are considered during the inspection and have to be taken into account before concluding that settlement cracks are symptoms of a more serious problem.
Stress cracks are looked at with a more critical eye.
Stress cracks tell a deer story as they may indicate the possibility of structural movement in the building or foundation. Earthquakes cause this type of crack as well.
Stress cracks always raise a red flag and cause a home inspector to look thoroughly at the underpinning and foundation of the building. These types of cracks may also point to over spanning of structural beams or other framing components.
The term span refers to the distance between two intermediate points where a beam, joist or board traverses over an open space. An over spanned board will bend significantly from the weight of the load it must support and the deflection will show up in the surfaces above it.
Stress cracks will not follow the joint of the drywall but rather tear across the drywall. The drywall is literally broken.
You will usually find stress cracks radiating diagonally from the corners of wall openings like windows, doors and hallways. The crack will be greater at one end and taper off as it disappears into the field of the wall.
If a professional has to be called in to repair settlement or stress cracks the cost for repair can soar to several hundred dollars.
To repair a crack in drywall, a joint rasp is used to cut down through the paper of the drywall into its gypsum body and then several thin coats of taping mud and webbing are applied to refill the hole. This process requires several days to allow each layer to dry. The final task is to attempt to match the existing texture (which by design is almost as individualistic as a fingerprint.) Sometimes it is actually easier to re-texture the whole surface from wall to wall.
With all that work most people just do not bother with the small cracks. Before having work done on a stress crack you may want to consult with a licensed structural engineer to make sure further cracking or movement is not expected and the overall integrity of the building and foundation is sound.
Like I said, the walls can be the first indicator of larger problems. However, I always reserved my opinion about cracks until I had looked over the entire building. In most cases, even the smaller stress cracks were old and not a problem, just a cosmetic nuisance.
Identifying holes in the walls are also a part of your inspection process.
Make notes on your inspection sheet of the location of holes in the walls for later repair.
Makes notes if you see any stains or discoloration in the walls.
Water stains are a big “red flag” for home inspectors. Water intrusion is one of the primary sources of damage to any structure. If you include the water used to put out a house fire, insurance claim statistics make it the leading cause of structural damage. Water ruins wood framing materials, associations wood destroying insects, wrecks wall coverings, and is the primary source of stimulating organic growth and dry rot.
Be sure to look behind the washer and dryer for signs of water stains.
Check to see if the wall is caulked at the top of the shower stall. There should be no crack in the caulking where moisture could enter the wall. This is one of those finds that show up over and over again. Fix this and your home inspector will wonder if a home inspector prepped your home or the sale.
Look for signs of stains and organic growth in the cabinets under sinks in the kitchen and bathrooms. Look around the tub and shower and at the wall behind the toilet.
Inspect carefully around the baseboards near exterior doors. Your inspection of the windows and doors may already have disclosed issues around these components.
As you get deeper into your inspection you will recognize that many aspects overlap. Issues created by the natural movement of a building and problems due to water intrusion reoccur through. The key is for you to recognize all of the issues you can and find ways to repair them economically.
Be sure to check closets from top to bottom. This area is commonly missed by homeowners and is where home inspectors often find stains and evidence of organic growth.
The general rule of thumb is; look everywhere that water could be present via plumbing fixtures or around exterior doors and windows.
Any old stains whose source has been repaired should be cleaned or painted over. Remember, if the inspector can not see it, it will not be in the report.
If you are aware of any plumbing leaks inside the walls they MUST be disclosed.
Home inspectors have moisture detection tools that are able to detect moisture in the walls and underlayment of floors. The tools are also used to determine if there is active moisture at a stain. If you try and disguise a water leak, the home inspector will very likely find it.
A new technology called inferred thermography is now being used to detect water and mold intrusion in buildings. It is a remarkable science that uses infrared cameras to “see” into walls, ceilings and floors. Thermography equipment is very expensive but prices are dropping on these cameras and more are being used by home inspectors.
Where there is moisture, there may be organic growth.
As stated before, organic growth (mold and mildew) has become a concern for many people and although a definite problem, has been heavily over hyped by the media.
Mold is everywhere. It is lying dormant in the drywall and wood components of the building. It exists at the exterior of the building.
The question is whether a person is sensitive to any specific species of mold. If they are it could be a serious problem.
Mold grows where moisture is persistent. If organic growth has been observed at the outer surface of a wall inside the building, it is unknown if there is mold inside the wall without further investigation. Exploring into the interior of a wall is outside the scope of a home inspection but if the home inspector is suspicious, he will recommend further evaluation.
If you suspect that there is a larger problem, be sure to contact an industrial hygienist for further investigation and testing. Eliminating mold can be an expensive process, but it is far cheaper than a law suite.
DO NOT TRY AND COVER UP EVIDENCE OF A POTENTIAL MOLD PROBLEM
If a wall appears to be severely bowing or twisted, a licensed structural engineer should be consulted. There may be issues related to the foundation, underpinnings or soils around the building.
Simple bowing of wood paneling may be due to settling of the building. An over-sized sheet of paneling could have been removed and trimmed to fit correctly.
Wood trim work around paneling should be checked for gaps and missing pieces.
Lath and plaster was a building process used for interior walls until the late 1950s. Thin pieces of cedar (called lath) were nailed on the 2×4 framing of the wall. One to three applications of wet plaster was then applied to the lath. In some cases, layers of wallpaper were applied on top of the plaster for decorating purposes. This actually added to the stability of the wall.
Inspect the lath and plaster for the same issues as found in drywall.
Cracks in masonry walls are also to be carefully inspected. There are two different types of cracks – those that have cracked in a “Z” pattern within the mortar and those that have actually broken the stone or brick.
If there is any water penetration through a masonry wall, the paint will peel from the surface. This is common with subterranean walls in foundations and garages.
WALL FINDINGS: REMEDIES AND SOLUTIONS
As stated above, repairing cracks in the walls can be a complex and daunting task. Cracks filled with Spackle compound have a tendency to reoccur. The filler is not able to expand or contract as the building changes shape through normal temperature and humidity variations.
A paintable, pliable silicone caulk can be applied with a finger to fill settlement cracks. Its elasticity will expand and contract allowing for slight changes in the crack without allowing it to reopen. The paint use has has to have an elastic quality as well.
Small holes such as those left by hanging pictures are easily filled with filler such as Spackle, taping mud or caulk. Use hard drying filler compounds such as Spackle or mud very sparingly. Excessive filler on a textured wall around a repair looks bad.
More obvious are holes or minor dents where a doorknob has hit the wall because of a missing or damaged doorstop. If the hole left by the doorknob is minor, simply apply a thin coat of filler to the hole, let it dry and then add a little more each day until it is flush to the wall surface.
If the doorknob punched through the wall, the repairs will take more work. There are several kits available at the local hardware store designed to repair holes left by doorknobs. There are several sites on the Internet that provide a variety of techniques for repairing holes in drywall.
The real trick is not so much repairing the hole as much as matching the texture. A good drywall technician can match texture very closely. Get a few bids from different sources if you have a large area that needs to be repaired.
If you have to remove damaged drywall that covers two or more framing studs it would probably be a good idea to contact a professional. Get at least two bids for the repair.
If you find water stains, eliminate the source of the water intrusion and then seal and paint the affected surface. If there is any evidence of organic growth further investigation and remediation may be necessary. Do not cover or disguise areas where mold is present. The ramifications of doing so can be quite extreme.
Local companies who restore buildings after fires are probably the best resource to quickly locate water intrusion problems. They have the equipment and expertise to trace the entry points of moisture. Look for a company that has the thermography equipment mentioned.
Organic Growth (Mold, Mildew and Fungus)
Surface mold and mildew can usually be removed with products designed for such applications. Contrary to popular belief, using a mixture of water and bleach is NOT a good cleaning solution. Laundry bleach is primarily made up of water and small amounts of chlorine. Mixing bleach with water to dilute it creates a solution that is mostly water.
Do you remember what must be present for mold and mildew to grow? Moisture! Diluted bleach is mold food.
If there is evidence of visible mold in areas larger than a few square inches, you will have to have a professional evaluation what further action should be taken. As with water intrusion issues, companies that do fire restoration are great sources for information about dealing with mold problems.
There are several websites that discuss mold issues. Several provide free kits for testing by the homeowner.
Some of the most common causes of deterioration are water intrusion, condensation and insect infestation. As with water and mold problems, the course of action is to determine the cause, eliminate it and repair as needed.
A qualified handyman is capable of these repairs. There are usually several listed in the phone book. Get multiple bids and ask for referrals. Do not hire the first person that shows up. If they fidget at your request for proof of the quality of their work, look elsewhere. If they are reputable, they will welcome your inquires.
If you have walls that are not straight up and down or appear to be out of whack, contact a structural engineer to determine why. These professionals usually charge a small fee for their inspection.
I can not even begin to tell you how many times I was asked if a wall was a “bearing wall.” My standard answer was “Every wall is a bearing wall without a licensed structural engineer says it is not.”