Five questions you should considering before selecting a contractor.

1. What is the best roofing system on the market?
There is not a single best roofing system available.  If there was everyone would be installing only that particular system.  Conversely, there are eight major families of roofing including (1) steep slope (inclusive of shingle, tile, shakes, etc), (2) built up roofs (asphalt and coal tar), (3) modified bitumen roofs (APP and SBS varieties), (4) metal roofs (standing seam, architectural, and pre-engineered), (5) coatings (acrylic, silicone, ceramic, etc), (6) sprayed in place foam roofs, (7) thermoplastic single ply membranes (PVC, TPO, EP, CSPE, etc) and (8) thermalset single ply membranes such as EPDM.  Each of these roof systems has its place in the market and its own distinct advantages.

A critical factor to a successful roofing project is using a contractor who is both familiar and capable of installing each type of roof system.  Such a capability will allow the contractor to evaluate your facility and the particular roofing characteristics of the building and suggest the roofing system(s) that meet the objectives of the owner

2. What should I look for when selecting a roofing contractor?
Any roofing system is only as good as the contractor who installs the roof.  The very best components of a roofing system can be specified yet if installed by an average contractor than the results of the project will be average.  Roofing projects are dependent on the contractor. 

The roof itself is fabricated on your building and those areas such as roof projections, edge details, penetrations, walls, and other areas of the roof requiring workmanship will determine the success of the project.  With this in mind, it is always important to look for a contractor who has a proven track record with multiple years of experience.  It is also important to look to a contractor that has the ability to install multiple roof systems so they can work with you to select the best roof system for your specific needs.  Criteria such as a written safety program, a drug tested work force, uniformed employees, and the use of their own employees versus sub-contracting are all important.  Financial strength, years in business, and like type references are also worth serious consideration. 
A final suggestion in selecting a roofing contractor is to ask for references that have had problems.  All roofing contractors have had jobs that have leaked.  The difference between the good contractors and the bad contractors is how they service the client after the sale.  Calling a few clients that have required attention after the initial installation is a good way to measure the contractor's commitment to his clientele.

3. What type of warranty should I buy and how do they differ?
There are multiple warranty types and lengths available.  Warranty terms such as “No Dollar Limit” (a.k.a. NDL), Non Pro-Rated warranty, total system warranty, material warranty, workmanship and material warranty, and single source warranty are all very different and each come with varying degrees of exclusions.  Prior to evaluating warranties, a buyer needs to consider who has authorized the warranty and keep in mind that the warranty can be written to benefit the warrantor.  A buyer should further consider the exclusions that are written into each warranty and determine if these exclusions are acceptable.  If the warranty and the exclusions do not meet the customer needs then changes or riders to the warranty should be requested.
The term No Dollar Limit refers to the fact that the warranty coverage is not restricted to the original purchase price and allows for price increases due to inflation and other cost factors.  This warranty is seldom exercised due to the need for catastrophic failure to occur in conjunction with increased roofing prices. 

The Non Pro-Rated warranty is a warranty that holds its value throughout the life of the warranty term.  This type of warranty is not discounted as the roof ages.  The warranty holds the same value in the first year of the warranted term as it does the last year.
Total system warranties are warranties that cover every aspect of the roof system.  This varies from material warranty that may only cover replacement materials and not the labor to install the new material. 

A single source warranty is structured in a way that there is one party responsible for both the workmanship and material of the entire roof system.  This covers all aspects of the roof system and the related workmanship required making any needed repairs.

As a final note, the buyer should determine what it is he or she would like to accomplish with a warranty.  This should take into consideration the reasons why the previous roof has failed, how long the building will be owned, what the current use and potential future use of the building may be, and who they want covering potential future needs. 

Remember, all roofs leak.  The question is will it be inside or outside of the warranty period.  With this in mind a buyer needs to determine how important it is to have the original installer who is most familiar with the roof do the repair work.

4. How much and what type of roofing insulation should I have installed?
The insulation component of a roofing system serves multiple functions.  Specifically to include provide insulating properties or R-value (R-value is the measurement of a materials ability to resist heat transfer), provide an acceptable substrate for the waterproofing membrane(s), provide compressive strength and resistance to roof traffic, and provide slope for proper drainage.  The type and the amount of insulation used varies with roofing objectives.  There are many types of insulation including fiberboard (non-coated, one side coated, six side coated, and high density), perlite, densdeck, expanded polystyrene, extruded polystyrene, polyisocyanurate, fiberglass, glass foam, and others.  Again each insulation type has its advantage.

5. What are my maintenance obligations once I have the new roof installed?
The owner’s maintenance obligations on the new roof can vary from nothing more than keeping drains and gutters free from debris to extensive preventative maintenance programs.  Each roof system and manufacturer has set requirements that are the responsibility of the building owner. 
It is suggested that the owner understand and know these obligations prior to purchasing the roof so there is a clear understanding of the total cost of roof ownership.