Troublesome and costly roofing problems are often the result of faulty initial design of the roof system. Design deficiencies are costly to correct, and usually can only be corrected during roof replacement. However, unless design deficiencies are discovered and corrected during roof repair or re-roofing, the problems relating to them most likely will recur. Some examples of faulty design are:
- Weak roof structures that deflect excessively under load, causing splitting of the roof membrane. - Inadequate roof slope, sagging roof structure, or insufficient number or location of drains, resulting in ponding water. - Inadequate provision for expansion and contraction at changes in deck material or direction, causing membrane splits. - Incompatible roof materials - i.e. the use of asphalt to adhere a torch-on material (APP).