Cracks, Bubbles, and Slopes - Oh my!

How do you recognize potential structure problems in a building?

The crack that didn’t say enough! It happens. We see a crack on a patio or wall of a building and think nothing of it. Or maybe we take the other extreme and think about the worse case scenario…that the property is a disaster and it’s time to walk away.  Either response might not be accurate.

Home inspectors, architects and engineers can investigate these possible “signs of trouble”, understand their causes and determine if it’s an area of concern. Most investors on the other hand don’t know what signs of trouble might look like or when a crack is just a crack.

The Structure Envelope

Explore the property, don’t be shy. This is your investment and you have every right to know its structural integrity. Anything that comes up as a “red flag” in your mind, the experts can check out and investigate thoroughly.

Pay close attention to the area known as the “building envelope”, as Fay Lorraine Sueltz, AIA mentions. The envelope includes: roofs, windows and walls.

David Swartz, a home inspector with Advantage Inspection Service and a contributor to the popular TV show, “House Detectives” on HGTV also advises to try every door and window in the home. Make sure they open and close. Swartz adds, “If a door or window is sticking or if there is evidence of past sanding it may indicate structural movement.”

Another tip Swartz mentions is to step back from each window and door and see if they look “out-of-square” i.e. not in alignment. Also look in the corners for casing separations or evidence of cosmetic repairs.

Cracks - Revealed

When does the size of the crack warrant further investigation? Swartz says, “A separation wider than the width of a quarter’s edge is notable and should be examined further, especially if multiple cracks exist in the same area.”

But which kinds of cracks are the most alarming? Evan Galen, AIA, Evan Galen Architects says, “If you ever see a diagonal crack you should be very wary. It means there is a stress on the existing structure.” It could be located along a wall, foundation, or window.

A diagonal crack is bad news. It means there is trouble. These kinds of cracks will show through any kind of material. Galen says, “It could be any size – ten foot long or four inches.” The diagonal could also be in a zig-zag direction.

These kinds of cracks could occur anywhere, but tend to appear more frequently in the corners. Galen says,” The presence of this kind of crack indicates a spot where there is weakness.” The diagonal crack could be caused by any number of things and is worth investigating.

Vertical and Horizontal Cracks

A vertical crack could appear due to the material drying process. For instance, a material could be shrinking like wall paper or wall paper trim. This could occur if the trim’s adhesive is not strong enough.

“A horizontal crack,” Galen says, “usually has to do with twisting of materials and it is very much like the vertical cracks in that it could be superficial.”  If you do find out that something on the horizontal plane is separating, then it needs to be explained.

Also note if the crack appears along the control joints. Sueltz explains, “Control joints act as a magnet. The cracks are driven to the control point.” For example: cracks on a sidewalk. If these score lines didn’t exist cracks would appear everywhere on the sidewalk. Sueltz adds, “The manmade cracks try to control where nature’s cracks will occur.”

The liability side of cracks

Could someone trip over the crack and hurt themselves? This potential risk may create a liability if the crack isn’t fixed. Swartz cautions,” The rule of thumb for trip hazards is a vertical displacement of a walking surface that exceeds ½ inch.”

Bubbles

Bubbles often occur on the outside of buildings where caulking is no longer adhering properly. Or they could appear next to an inside window. Moisture could be coming in or around the frame of a window, or near a staircase; hence the bubbling effect.

Whatever the cause, a bubble suggests there is movement in the foundation, staircase, or the building. It could be shifting in a diagonal way, but covered by cloth or some other material. Like with diagonal cracks, a diagonal bubble could indicate a big problem.

Galen advises, “Whenever you see a bubble it means something is happening on the side that you can’t see.” For example, if you look at caulking and it is bubbling outward, then there is some kind of pressure from inside. It could be caused by water, air, or the structure could be settling or shifting.

A bubble could be a ½ inch or one that runs along a whole side of a window. Galen says, “Bigger does not necessarily mean that there is a worse problem. It’s an indication that the problem might be more advanced because it’s older. Or the area has been repaired and is starting to bubble again.”

Slopes

Pieces of a building have a proper direction such as: flat, up and down, or at a specific angle. If a section of the building is moving in a different direction from its natural orientation, then something is happening.

Floor line: If you’re unsure where a floor is sloping try rolling a marble on tile or wood floors as Swartz suggests. Be on the lookout for any areas with excessive bounce in the floor.

Watch out for baseboards. Swartz says, “They can telegraph structural sins present at the property.”  At the time of installation baseboards are mounted flush with the floor’s surface. However, over time a gap could develop between the bottom of the baseboard and the floor surface. This might be caused by structural movement.

Roof: A roof could sag when the material is too heavy for the structure.  If the home is the only one in the neighborhood with a tile roof it might have been installed without a review by a structural engineer.

Swartz says, “A rule of thumb for examining the roofline is to walk around the perimeter and view a straight line from the roof’s edge to the peak of the roof looking for sags.”

Chimneys: While you’re examining the roof don’t forget to explore the chimney.  Determine if the chimney is leaning or if there is a separation at the house transition points. Swartz cautions, “If a gap at the chimney gets wider at the top it indicates it is rotating outward.”

Other causes for sloping could be organic related. Galen says, “If you put a key in a piece of wood and it goes inward and you get powdery dust it could mean there is infestation or dry rot.”

Don’t try to diagnose the cause of slopes, bubbles or cracks yourself. Ask for an evaluation from experts in home inspecting, structural engineering and architecture.

Side Bar – Contacts

Evan Galen, AIA
Evan Galen Architects
(212)427-7989
http://www.evangalenarchitect.com.
evan@evangalenarchitect.com

Fay Lorraine Sueltz, AIA
8677 La Jolla Village Drive #1231
La Jolla, CA 92037
(858) 587-0995

David Swartz
Advantage Inspection Service
Direct (602) 469-3175
http://www.azinspect.com
http://www.hgtv.com/hgtv/rm_resources_expert_advice/article/0,1797,HGTV_3782_2610841,00.html
http://www.hgtv.com/hgtv/rm_safety_other/article/0,1797,HGTV_3794_3056056,00.html