Roof Systems

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The roof of a home is one of the most common areas for water penetration to occur. Can you identify the different signs and degree of roof failure?  The following paper helps you do just that.  From flashings to life expectancies, it’s all here.

Method of Inspection
There are several methods of inspecting a roof.  Typically, it is walked on, checked from a window from above, by a ladder at the eave, or from the ground with binoculars.  If at all possible, the roof should be walked on, unless it would damage the material, such as older slate, or it would be unsafe or dangerous to the inspector.  As a minimum, a ladder should be placed at the eaves, and the evaluation performed from that location.  Windows from above provide an excellent opportunity to evaluate as much of the roof as possible from that location.  The last resort is inspecting it from the ground with binoculars. 

Inspectors carry extension ladders in some markets. Florida communities are mostly ranch or one-story homes. Most home inspectors in Florida carry folding ladders. Many northeastern markets, such as Philadelphia, have mostly two-story homes, so many home inspectors carry extension ladders.

Townhouses and inner city houses frequently have flat roofs that are difficult to get on without an   extension ladder.  In many cases, there is a hatch on the second or third floor that provides access to the roof.

Roofing Characteristics
There are nine characteristics of a roof that you should consider in your evaluation:

1.         Slope                            6.         Remaining Life

2.         Material type                  7.         Style

3.         Maintenance                  8.         Structure

4.         Estimated Age                9.         Flashings

5.         Design Life

Slope
Roof slope is determined by vertical rise over horizontal run, expressed in inches, the second number always being 12.  For example, if a roof rises at a rate of 6 inches per foot (horizontal), it is a 6/12-slope roof.

Roofs with slopes of 8/12 or less can be walked on in most situations. Some people do not have any difficulty climbing almost any roof, while others have considerable difficulty. You should never walk or climb a roof that you do not feel safe climbing.

A roof that is flat, close to flat or has depressions, and allows water to collect or pond, may be a defect. This will depend on the extent of the ponding and the amount of water that collects. The National Roofing Contractors Association (NRCA) says that if ponding water evaporates within 48 hours of the time it stops raining, it can be considered acceptable.

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Maintenance and Life Expectancy   Roof Materials   Common Defects
Related Components      Roof Structure