Wanted: Roof System Historical Info

by Kent Mattison, PE

Roof maintenance is the most neglected factor affecting a roof system's performance.  Part of roof maintenance is keeping track of its performance and knowing its history, so it can be properly cared for.

When we are asked to perform a roof evaluation, we are usually asked to determine:

• The roof system's present condition

• Sources or potential sources of roof leaks

• Cost-effective maintenance, repairs, or replacement options in order to extend roof service life

Visual analysis, core samples, and infrared moisture surveys are the primary tools used to perform this evaluation from which recommendations are based.  However, historical data is a key component in roof analysis, and yet it is often the most ignored component.

It's too often assumed an experienced roof consultant can walk a roof and based strictly on the roof's visual appearance, tell a building owner its problems, the causes of these problems, the best solution to these problems, and the roof's anticipated future performance.  And we, as roof consultants, sometimes assume we see the entire picture from our visual observations.  But very often, if we are provided complete and accurate historical information, our overall assessment and recommendations may change.

It's somewhat like evaluating a used car.  It may be clean, have a great paint job, look pretty good visually and test drive well, but until you know its mileage, how it's been driven, its age, accident-repair-and maintenance history, and warranty information, you aren't going to feel comfortable buying the car.

We need the same type of information to assess a very essential and costly building asset, the roof.

Yet it is one of the most difficult pieces of information to obtain.  It's rare that no historical information actually exists, either written documentation or stored in someone's head.  But if the effort is made and time is taken, the information can usually be found.

What type of information is needed and why is it so important?  

 Roof System Product Manufacturer(s)

Depending on the type of product, the manufacturer may or may not be visually identifiable.  But by knowing the product's manufacturer, we can better predict its performance based on our knowledge of that product's historical track record.

 Age

Knowing the age of the roofing system can provide a more accurate estimate of the remaining service life and types of problems that may be anticipated.  

 Installing Contractor

The installation of the roof system will usually have the greatest impact on the long-term performance of that system.  The roofing contractor can provide some of the most valuable information regarding problems encountered during construction, means and methods of installation, etc.

Roof Plans and Specifications

Often times building plans seem to be a very difficult item to locate.  However, they can be one of the most helpful tools in determining what should be expected from the roof's long-term performance.  Plans can also give some indication as to why problems have developed or if the roof system was even installed in accordance with the plans and specifications.  

 Past Problems, Leaks and Repairs

Though some defects, leaks and repairs may be visually identifiable, the cause or source of the problem or need for the repair may not.  This type of information can make a big difference in determining the anticipated remaining service life and most cost-effective approach to maintaining the roof system.

 Weather Conditions during Installation

Knowing what the weather was like during construction can help identify a specific problem that is occurring.  Temperature, moisture, humidity and wind all affect the installation of various roof systems differently.

 Storms

Having information regarding major wind, hail or rain storm events helps identify the cause of some defects and/or what types of defects can be expected to be found.

 Warranties

This item should possibly be the first one listed due to the interest and questions it always creates.  Warranties are too often looked at as the ultimate insurance against roof problems.  Roof system manufacturers provide labor and material roof system warranties for 10, 20 or even 30 years at a fairly nominal fee, and not necessarily because they're confident all their roof systems will provide leak free service for that period of time.  They know, based on experience, that a vast majority of building owners will not file a warranty claim because they have lost, misplaced, forgotten, voided the warranty, or do not even know that a warranty exists.

This is often a very costly mistake when a roof problem does develop within the warranty time period.  Having the warranty on file can save a significant amount of money in repair or even replacement costs when the deficiency can be attributed to material or installation problems.