Understanding the warranty requires, first, understanding the
difference between a contractor’s warranty and a manufacturer’s
warranty. The manufacturer’s warranty is typically limited to
defects in the product that result from the manufacturing
process. It is not a negotiable instrument.
The contractor’s warranty is your warranty and guarantees the
workmanship and services you agree to provide. You negotiate
with the client, and, typically, your warranty becomes a part of
the job contract or agreement that you sign with the customer.
The following discussion concerns only our manufacturer’s
How Long Is Long Enough?
CertainTeed warrants its siding for the lifetime of the original
owner. This lifetime limited warranty is our promise that
CertainTeed siding is manufactured to consistently high,
reproducible standards that your customers can count on.
Because few people live in the same home their entire lives,
CertainTeed’s warranty is transferable to the subsequent
homeowner, making an investment in CertainTeed siding a
selling feature of the home. Upon transfer, the warranty converts
to a pro-rated warranty with a duration of 50 years from the
date of installation.
There are some competitive brands available with lifetime
warranties to the original owner and the transferee. It would
appear these warranties are “forever” warranties. We believe
this is absurd. First, nothing lasts forever—not products or
companies. Second, a warranty is only as good as the company
behind it. It may be to your advantage to point this out to your
customers when they are considering competitive sidings.
CertainTeed has been in the building materials business since
1904 and has produced vinyl siding since the 60s. Our ability to
produce a quality product for decades at a price homeowners
can afford testifies to the value of both the product and the
warranty: We make siding that lasts a very long time, and we
guarantee it for as long as makes good business sense.
Companies that guarantee their products “forever” may
have a difficult time staying in business forever.
This chapter discusses the defects that are covered by the
manufacturer’s warranty and those that are not:
• Oil canning
• Blow off
• Water intrusion
What Is a Manufacturing Defect?
First, CertainTeed siding and accessories are guaranteed to be
free from manufacturing defects in material and workmanship.
Second, CertainTeed’s warranty guarantees consistent gloss
levels and colors from batch to batch. Panels from two different
cartons which do not match in gloss and colors are defective.
Third, CertainTeed siding is guaranteed to weather evenly on any
one wall. Different exposures to the elements may cause the siding
to weather differently from wall to wall over time. Everything
that is left in the sun weathers, but it should all weather at the
same rate. All of our siding colors and accessories are tested
outdoors and in accelerated weathering machines. These colors
are our standard for normal weathering, and when contacted
about a weathering claim, we use these standards as the basis
for resolving the claim. Uneven weathering is quite noticeable
because it produces a checkerboard effect. It is a manufacturing
defect, and CertainTeed will replace siding and accessories that
have weathered unevenly.
Occasionally, homeowners attempt to replace a few damaged
panels in a wall of siding. This causes weathering to become
very noticeable, because the new panels will not match the
normally weathered panels.
Finally, though siding is not typically warranted against “acts
of God,” CertainTeed replaces siding damaged by hail to the
extent that homeowner’s insurance does not pay for
the damage. (Subject to certain provisions set in the
Oil canning is a terminal problem for panels with traditional
nail slots; once it occurs, the face of the vinyl siding is
permanently distorted and must be replaced. It is a wrinkling or
buckling of the panel face, so called because when the siding
buckles, it has the appearance of the bottom of an oil can. It
occurs because the siding is not free to “float” and is almost
always an installation problem.
The most common causes of oil canning in panels with
traditional nail slots are:
• Improperly cut panels: Panels that are cut too long will oil
can because they have no room to expand. Vinyl siding
should be cut to allow 1/4 to 3/8 in. movement in
J-channels, cornerposts, and other accessories.
• Tight nailing: Galvanized roofing nails must be driven
through the center of the nail slots at least 3/4 in. into a solid
substrate, with up to 1/16 in. clearance between the
head of the nail and the siding. If the nail is driven tight
against the nail hem, the siding “oil cans” because it cannot
move as it expands and contracts.
• Expansion and contraction are also restricted if the panel is
nailed at opposite ends of the nail slots. For horizontally
installed siding, if the panel is nailed at the extreme left of the
left-hand slot and the extreme right of the right-hand slot, it is
effectively fixed in place. As the ambient temperature varies up
or down from the temperature at installation, the nails will
restrict the panel’s movement to the area inside the nails,
causing the vinyl panel to oil can. Always nail in the center
of nail slots. Because vertically installed siding expands and
contracts in one direction (down) rather than equally across
the panel, vertical siding is nailed at the top of the top slot and
in the middle of all remaining slots.
• Face nailing, nailing through the front of the panel
rather than through the nail slots, also causes
siding to oil can. Even novice installers rarely ever make
this mistake on a flat wall. However, it is not uncommon for
novices to nail through the panel face when shutters,
strapping for gutters, or outdoor lights are installed.
Experienced installers drill holes three times the diameter of
the screws, bolts, or nails being used to fasten the objects in
the siding. This provides clearance so the siding can move
Under normal conditions, properly installed vinyl siding from a
reputable manufacturer will not blow off. Angular locking legs
and properly fitted trim yield secure connections, even under
high wind pressure.
Most blow-off begins at either the top course of siding or under
windows. It occurs because the top course is not properly
secured. Installing a J-channel and undersill trim or a cornice
receiver/cornice molding combination will generally prevent
CertainTeed Vinyl Siding Master Craftsman Education & Development Program
CertainTeed Vinyl Siding Master Craftsman Education & Development Program
this. If the top edge of the last course of siding is pushed under
and locked into the trim, the siding will not blow off under normal
wind pressure. If high winds are a problem, the most
secure application is to punch nail slots through the face of the
top panel. Then hang the top panel as you would a normal siding
panel, covering the nail heads with the cornice receiver/cornice
Siding is not a water-proofer; it is a water shedder. All problems
of water intrusion, especially around windows, doors, trim,
lights, etc. occur because the area around these openings is not
protected by flashing or another water diverter. For example,
unless directed otherwise, water will run down channels
surrounding windows and under, not over, siding. The length
and width of flashing you will have to use depends on the
opening and the type of accessories, but it is essential that
flashing be wide and long enough to direct water onto the butt
leg of the siding. The butt leg acts as a gutter, carrying water to
weep holes and ensuring proper drainage to the exterior
surface of the panel.
When in doubt, flash it. If you’re not sure whether an opening
should be flashed, play it safe and flash it. It can’t hurt, and
flashing around an opening is always significantly less expensive
and time consuming than a call back to repair water damage.
Some Common Warranty Questions
What is “normal” weathering?
Normal weathering is exposure to sunlight, extremes of weather,
or atmosphere that causes any colored surface to gradually,
fade, chalk, or accumulate dirt or stains. The severity of
weathering depends upon where the building is located, the
pollution in the air, and other local conditions over which the
siding manufacturer has no control.
If something hits the building and dents or
cracks the siding, is replacement covered under
No. While CertainTeed siding is strong enough to withstand the
normal dents and dings that can be expected during installation
and normal use, we have no control over baseballs, bats, tree
limbs, car bumpers, etc. For that reason, siding is not
warranted against dents or cracks caused by impact.
Is siding guaranteed by CertainTeed
While all CertainTeed siding meets or exceeds ASTM minimum
standards, blow-off is outside the manufacturer’s control. The
type and condition of the substrate, the type and depth of the
fasteners, the location of the nails, the direction the house faces,
wind gusts, and positive and negative pressures all impact the
ability of the siding to withstand wind. Because it is impossible
to control all these factors, CertainTeed vinyl siding is not
warranted against blow-off.
What is a wind load rating?
Wind load testing is a laboratory measure of the siding’s ability
to withstand positive and negative wind pressure. This rating is
CertainTeed’s assurance that, based on ASTM D5206 Standard
Test Method for Wind Load Resistance, the siding you purchase
is manufactured to withstand specified wind load pressures
when that siding is nailed to studs with roofing nails or staples
penetrating -3/4-in., spaced 16 in. o.c. The testing verifies that
the locking devices are secure and tight fitting and nail hems
are sufficiently durable—even when buffeted by the wind.
It is also important to understand that wind load rating is a
relative number. It is calculated in an equation where the
variable is a location’s “exposure.” For example, wind load
rating for siding on a building that is 33 ft. high or less, at a
wind load pressure of 85 psf, in a particular exposure (A) is
180 mph. The same siding, on the same building, at the same
pressure, in a different exposure (D) has a wind load rating of
All CertainTeed siding has passed wind load requirements for
Dade County, Florida, and the Texas Board of Insurance. These
are the toughest wind load requirements of all code regulations.
Are kinks in the siding covered by the warranty?
Probably not. Before it is packaged and then again before it
leaves the factory, all CertainTeed siding is inspected for quality.
It is stored flat, on pallets, and it is shipped flat, on pallets. In
the unlikely event that the siding you receive from the factory
has kinks in it, we will, of course, replace it free of charge. But
it has been our experience that most kinks occur when siding is
improperly stored or transported after delivery. It should always
be stored flat, on a solid surface, and transported in such a way
that cartons are not bent. Damage as a result of failure to
properly store and/or transport the siding is not covered by our
Do I have to use CertainTeed accessories when
I install CertainTeed siding?
You should. The accessories that are recommended for
CertainTeed siding have been designed and manufactured by us,
to our exacting specifications. They allow the siding to perform
optimally, particularly as it expands and contracts. Using generic
accessories will likely result in fittings and locks that are too
tight or too loose, or allow water to run behind the substrate.
Also, accessories from other manufacturers are likely to
weather differently from CertainTeed siding, causing unsightly
variations in color.
Using generic accessories will not void the warranty. However, if
a problem is caused by another manufacturer’s product or
accessory, the claim will be denied.
Is water damage to the house or the substrate
covered by my warranty?
No. Siding is a system. When properly installed, the system will
shed water. Therefore, it is the installer’s responsibility to make
certain that the substrate is properly prepared, every course of
siding is properly locked and fastened, and all openings are
flashed. When the system is installed correctly, water is diverted
over rather than under the siding, and neither the substrate nor
the building gets wet.
What about underlayment? Is it included in the
No. As you know, there’s a saying among siding installers: Vinyl
siding looks only as good as what’s under it. If the underlayment
is wavy, eventually the siding will take on the same wavy
appearance. CertainTeed has no control over the types of
underlayment and their installation, but providing a smooth, flat
surface is mandatory when installing vinyl siding.
What about so-called “professionally accepted”
This falls under the “that’s the way we’ve always done it”
explanation when something goes wrong. CertainTeed siding
must be installed according to the written instructions in this
manual. This is particularly important with Cedar Impressions,
CedarBoards, and Northwoods products because their
installation instructions are different from vinyl. If so-called
“professionally accepted” techniques are found to be the cause
of any siding problem, the claim will be rejected.
Instructions for installing CertainTeed siding and accessories
are included in this manual; basic must-do instructions are also
included on our packaging. Finally, technical help for installers
is available at 800-999-3654. We strongly recommend that
before starting a job, you review our installation instructions for
the type of siding you’re using on that job. And if you run into
an area not covered by our standard instructions, call Consumer
Service. Our trained staff will be happy to recommend an
What should I do if I have a warranty claim?
Simply call Consumer Services at 800-999-3654 if you have a
technical question about CertainTeed siding or if it doesn’t
measure up to your expectations. If you’re calling with a
specific product concern, please know the product name, style,
and color; the name and location of the distributor who sold
you the siding and accessories; and the date you installed it. If
we can’t answer your question immediately, we will contact
someone who can and get back to you.
CertainTeed Vinyl Siding Master Craftsman Education & Development Program
• CertainTeed siding is guaranteed not to peel, flake, rust,
blister, or corrode.
• CertainTeed guarantees consistent color and gloss from
batch to batch.
• CertainTeed siding is guaranteed to weather evenly on the
• Oil canning is almost always an installation problem and is
not covered by the manufacturer’s warranty.
• Vinyl will sag and have to be replaced if exposed to
excessive heat from reflected sunlight or a barbecue. This is
not a manufacturing defect.
• CertainTeed siding is not warranted against blow-off.
• Siding sheds water; it will not waterproof a house. For that
reason, it is not guaranteed to prevent water intrusion.
Proper flashing is always required.
• To meet the requirements for warranty protection,
CertainTeed siding must be installed according to our
written instructions. “Professionally accepted” installation
techniques may not comply with CertainTeed’s instructions
and may void the warranty.