SELECTING
THE RIGHT MATERIAL
When choosing a roofing system for your home, the factors you should
consider are Weight, Durability, Fire-Rating, Appearance and Cost.
The appearance you want from your roof and what your budget can
afford should be determined before you start shopping. Also, know
what type of structure your home has. This will determine how much
weight the structure can hold and whether it will be necessary to
reinforce or apply plywood before the new roof application.
When considering the durability of a material, check to see what
kind of manufacturers warranty is offered and what type of
warranty the contractor will offer. Remember, the warranty offered
is only as good as the manufacturer or contractor who stands behind
it.
The fire rating is a critical factor in selecting a material and
protecting your home. Since most roofing materials are combustible
to some degree, they may be vulnerable to external fire exposure.
Some roofing materials will propagate a rapidly spreading fire over
the surface or may allow the fire to penetrate the roofing material
and to communicate to the interior of the building; this should
be avoided.
The most nationally recognized testing for a material is the guidelines
of the Underwriters Laboratories, Inc (generally referred to as
the U.L. rating). The criteria used for this testing determines
if a roof system is rated Class A, B, or C. Your homeowner insurance
premium may also be affected by the fire-rating of your roof. Class
A roofing systems do not require frequent repairs to maintain their
fire retardant properties, Class B may require some maintenance.
To get an idea of what is available on the market, you can check
the local supply houses or ask your prospective contractor for samples
and brochures.
Once you have narrowed it down to a few materials that are suitable
for your home and budget, you may want to get some addresses of
homes that have been roofed with these materials. Feel free to ask
your prospective contractor to provide you with proposals for any
options you may be interested in.
Options for Pitched Roofs, or roofs that have a minimum of a 2-½/12
pitch, include Composition Shingles, Shakes, Tile, or Metal.
Composition Shingles are the most popular and affordable solution
for a pitched roof; they have a class A fire-rating. If you are
converting an existing shake roof to a composition roof, it will
be necessary to install plywood. Make sure your contractor is using
½ inch cdx plywood; we do not recommend OSB Board, even though
it is allowable by code.
Unlike the shingles of many years ago, the composition shingles
available on the market presently are an architectural design and
are of much better quality. There is a range of grades of shingles
i.e. 25 year, 30 year, 40 year, and up and a range of colors and
styles. Talk to your contractor about which shingle is the most
suitable for you.
Shake roofs are still an option; however, they must be a minimum
class B fire rating. If you are considering a shake system, insist
that it be a Premium Heavy Shake; the quality is superior to other
shakes on the market.
Tile roofs are frequently chosen to match the architecture of the
home. This type of roof system is on the high end as far as price.
The underlayment is critical to the integrity of this type of system.
If you are installing a tile roof, you should consider applying
2 layers of #30 felt or a SBS underlayment. Tile roofs are fragile;
if you need to maintenance your roof frequently you should take
this into consideration. Tile roofs typically weigh more than other
types even though lightweight tiles are now available.
Metal roofs have gained in popularity. This type of system is pricey
and has some drawbacks in our area. There is a high heat transfer
and therefore has a low fire rating and does not fare well in an
ocean environment. Metal roof systems can be somewhat noisy. They
are also slippery and repairs will be more expensive than other
types of roofing systems.
Options for Flat Roofs, or roofs that have less than a 2-1/2/12
pitch, include Tar & Gravel or Capsheet, Torch-Down single-ply
systems, Acrylic system, and PVC single-ply systems.
Tar & Gravel or Capsheet system was about the only option up
until several years ago. This type of system consists of a base
sheet, mopped with 3 plys of hot asphalt with felt in between, and
covered with either a layer of gravel or a mineral surface capsheet.
This system is quite heavy, weighing 550 lbs. per sq. This type
of application requires a kettle with hot asphalt to be at the job
site, which produces an offensive odor; it also is conducive to
higher safety risks. This type of application is becoming more obsolete
as other flat roof systems offer more advantages for the same amount
of money.
Torch-Down single-ply systems are an asphalt based roof system
with a small percentage of rubber. This does make this system more
flexible than a hot-mop application, but it still inherits the same
deficiencies. This system can be repaired more efficiently and with
better success than a hot-mop and is more attractive. This system
is applied with a torch, thus eliminating the odor produced by a
hot-mop. This roof application is rated to be a 15 year roof, but
we have been seeing failure prematurely.
Acrylic systems are a long-term solution to end flat roof problems.
This type of system is costlier and is dependant on weather conditions
to properly cure. This type of system is applied with an industrial
sprayer or can be rolled on smaller projects. The system consists
of a primer, 2 layers of base coast, a layer of polyester fabric
to shear up the strength and two top coats. The application can
frequently take weeks to complete because of atmospheric conditions.
PVC systems are considered to be the state-of-the-art applications
for flat roofs; there are a variety of manufacturers. This type
of roof system is hot air-welded and uses custom, pre-manufactured
flashings and vent covers. This makes the flashings all part of
a 1-piece membrane, requiring no maintenance. This type of application
is completely odorless and is being used in numerous commercial
applications such as Burger King and McDonalds to name a few. A
contractor with the right experience and equipment can offer this
system with a cost that is competitive with other flat roof systems.
This type of roof system can be expected to last 25 or more years.
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