How To Look At A House

McGarry and Madsen's home inspection blog for buyers of  

site-built, mobile/manfuactured and modular homes

How can I tell if an asphalt shingle roof manufacturer's warranty rating is 20 years, 30 years, or more?

Sunday, June 16, 2019

Asphalt shingle manufacturers offer “lifetime” warranties that are usually rated from 20 to 50 years. This type of warranty only provides protection for manufacturing defects in the roof materials if they deteriorate or fail before they should, and the warranty can be voided due to improper installation or inadequate maintenance of the roof.

    The roofing contractor provides warranty paperwork at the time of installation, so you might be able to receive the warranty information from the seller of a home you are buying. The warranty may, or may not, be transferrable to a new owner of the home. Also, many warranties are pro-rated and only cover replacement materials. But we are assuming your concern is not the details of the warranty, but the rating of the shingles.

    If the homeowner cannot provide paperwork on the the warranty, your home inspector may be able to tell you the approximate rating of the shingle using a roofing gauge tool (shown above) that measures the thickness of the shingle. Thickness is directly correlated to life expectancy and, although not an exact measure, can give you a good idea of the how long the shingles can be expected to last.

    Unfortunately, the intense Florida sun batters shingles with UV-light and shortens their actual life compared to their rating and installations in other states. You should not expect a 30-year shingle, for example, to last longer than 25 years at best.

• • • • • • • • • • • • • • • • • • • • • • • • • •

Here’s links to a collection of our other blog posts about SHINGLE ROOFS:

Why is granule loss a problem for an asphalt shingle roof? 

What causes roof shingles to curl up at corners?  

Why is premature curl of roof shingles a problem?

Can I put a new asphalt shingle roof over an existing shingle roof on a manufactured/mobile home?  

How can I tell if a roof has more than one layer of shingles? 

What is the life expectancy of an asbestos cement shingle roof?  

Does a roof with multiple layers of shingles last longer? 

Why is a popped nail in a shingle roof a problem? How do I fix it?

What are the dark lines running parallel to shingles on my roof?

What is the average lifespan of an architectural (dimensional) shingle roof? 

What is the average lifespan of a regular (3-tab) shingle roof?

What does "lack of tab adhesion" in an asphalt shingle roof mean?

What is the minimum pitch/slope of an asphalt shingle roof?

Why are there sometimes damaged shingles around an area of roof shingle repair or the tie-in of a new roof?

What's the difference between an "architectural" and a regular shingle roof? 

• Why is an asphalt shingle roof difficult to inspect when wet right after it has rained?

• What causes small areas of pitting or pockmarks in an asphalt shingle roof?  

     Visit our ROOF AND ATTIC page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles. 

Water Heaters

Water Heater Age

"What Are The

Signs Of..."

Septic Tank Systems

Structure and Rooms

Plumbing Pipes

Termites, Wood Rot

& Pests

Sinkholes

Stairs

When It First

Became Code

"Should I Buy A..."

Park Model Homes

Site

Shingle Roofs

Safety

Stucco

Remodeling

Wind Mitigation

Roof and Attic

"Does A Home

Inspector...?"

Pool and Spa

"What Is The Difference Between..."

Radon

Brick

Plumbing

Concrete and

Concrete Block

Metal Roofs

Foundations

Modular Homes

Rain Gutters

Mold, Lead & Other Contaminants

Condominiums

Older and

Historic Houses

Crawl Spaces

Mobile-Manufactured Homes

Building Permits

Life Expectancy

Clay Soil

Insurance

Floors

Insulation

Toilets

Exterior Walls

& Structures

Generators

Common Problems

HUD-Code for

Mobile Homes

Garages and Carports

Flat (Low Slope) Roofs

Electrical Panels

Sprinkler Systems

Electrical Receptacle Outlets

4-Point Inspections

Hurricane Resistance

Frequently Asked Questions (FAQ)

Home Inspection

Heating and Air Conditioning

Building Codes

Fireplaces and Chimneys

Inspector Licensing

& Standards

Energy Efficiency

Washers and Dryers

Electrical

Kitchens

Doors and Windows

(placeholder)

Cracks

Electrical Wiring

Click Below  

for Links

to Collections

of Blog Posts

by Subject

Plumbing Drains

and Traps

Appliances

Smoke & CO Alarms

Aging in Place

Top 5 results given instantly.

Click on magnifying glass

for all search results.

Bathrooms

Lighting

AFCI, CAFCI,

DFCI, & GFCI

Sinks

Air Conditioner & Furnace Age/Size

Attics

Electrical Switches

Siding

Search

This

Site

Water Intrusion

Electrical - Old

and Obsolete

(placeholder)

Foundation Certifications

Tiny Houses

About Us

(placeholder)

Wells