Foundation Settlement Causing Brick and Drywall Cracking - When Do You Call an Engineer?

Stair steps type cracking in masonry can be an indication of foundation settlement. The settlement of the foundation is generally caused by either: 1) the poor compaction of the foundation soil during construction, 2) using an improper type of soil (such as soil containing large amounts of organic material), and/or 3) soil experiencing excessive moisture or by excessive loadings.

Another indicator of foundation settlement is drywall cracking around the openings in the exterior wall.

The typical settlement caused by a poor compaction occurs in the first couple of years after the completion of the house and typically will reach stabilization after the soil has adequately consolidated. Settlement caused by the deterioration of the organic material under the foundation would occur over a longer period of time after the completion of the house. The presence of excessive water in the foundation soils and or excessive loading can occur at any time during the life of a structure.

Typically when settlement is the cause of stair-step cracks, the stair-steps build upward toward the location of the settlement and a corresponding stair-step crack can be found to indicate where the settlement has taken place. For instance, if the front left corner of your house were settling one might expect to finds a stair-step crack at the front wall, building upward toward the left and another at the left wall, building upward toward the front.

Typically when stair-step cracks are noted it is necessary to evaluate the interior of the structure. If no deficiencies are noted internally, the settlement is sometimes considered veneer settlement only, which is generally not a structural concern. When deficiencies are noted on the interior such as rippling of wallpaper, cracks in drywall and/or separations in molding around doors, windows, and/or tops and bottoms of walls, the settlement might be considered to be that of not only the veneer but also of the pier and curtain wall supporting the wood stud wall, which could be a structural concern.

Another less known force, which is often misinterpreted as foundation settlement is a "push out" force caused by either the deflection of roof rafters or the spreading of the roof. When there is not adequate vertical support for the rafters or when excessive loading such as during a high wind event or heavy snow event the roof can sometimes tend to spread. If a front-to-back roof spreads, it will tend to push out on front and rear exterior walls, which can sometimes lead to misjudgment of the cause of the cracking and often to costly, incorrect, unnecessary repairs.

If you suspect that you have a foundation issue, it is advisable to hire a forensic structural engineer to assess the situation. Typically the best means of proceeding is to first call 3-4 local foundation repair companies that offer "free estimates" and have them assess the issue. Often times these companies are on the side of caution and "estimate" that you need 2-3 more piers than are actually required. This is the time that a forensic structural engineer can help. It will probably cost in the neighborhood of $700-$1,000 for an engineer to come check it out, but with the piers typically costing between $800-$1,000, if the engineer can deduce that those extra 2-3 piers are not necessary, you have saved $1,600-$2,000 and have an engineer's letter to disclose should you want to sell your house.

A good structural engineer is expensive, but so are foundation repairs. This is especially true when the person who is sent out to your house is more of a "pier salesman" than a foundation expert. Hopefully these suggestions will save you money.



Article Source: http://EzineArticles.com/7123744