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WIND DAMAGE to ROOFS
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More Information

Asphalt Roof Shingle Wind Damage Causes & Evaluation
InspectAPedia®  -    

  • Workmanship as a cause of wind damage to roofs
  • Shingle sealant defects as a cause of wind damage
  • Disaster-resistant roofing shingles
  • Do we need to remove the protective cellophane strips from the glue strips on asphalt shingles? No.
  • Asphalt roof shingle blow-off, photographs
InspectAPedia offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. Our contact info is at InspectAPedia.com/Contact.htm.

This document discusses how to evaluate wind damage to asphalt shingle roofs and tells readers how to identify & explain the most-common failure mechanisms such as improper nailing, failure of shingles to seal. This information is useful when considering how to obtain asphalt roofing shingle failure claims assistance.

These defects occur on both organic-mat or fiberglass-mat asphalt roof shingles. Readers are also invited contribute roof failure information to the web author for research purposes. web author for research purposes. Readers should also see ASPHALT SHINGLE INSTALLATION.

For clay or concrete tile roofs, see CLAY TILE WIND & SEISMIC CONNECTORS where we describe special connectors used for roofing tiles in high wind, hurricane, and seismic areas. Standard clay tile roof connectors are discussed at CLAY TILE ROOF CONNECTIONS.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Workmanship and Wind Damage Assessment for Asphalt Shingle Roofs

As stated in Best Practices Guide to Residential Construction:

Most shingles carry a windresistance rating of 60 miles per hour as tested under ASTM 3161 or UL 997, while specialty shingles may be rated to as much as 130 miles per hour. While laboratory tests may not predict actual performance in a storm, a higher rated shingle will likely perform better than a lower rated one.

Shingles rated at over 100 mph are often specialorder items and typically require six rather than the usual four nails per shingle. Adding two extra nails and extra dabs of plastic roofing cement to a regular shingle can also increase its performance in high-wind conditions (see “Fastening (Nailing) Requirements for Asphalt Shingle Roofs” and “Manual Sealing Requirements for Asphalt Shingle Roofs” ).

A wind-resistance rating is not the same as a warranty. Shingles that carry a wind-resistance warranty generally require that the shingle tabs have been adequately sealed to the adhesive strip and most limit wind coverage to five or ten years from installation. In cold, cloudy weather or on a steep north-facing slope, manual sealing with roofing cement may be necessary.

Roof Installation Workmanship: Fasteners/Nailing Problems, Wind Damage appeared to have led wind blow-off of these Atlas shingles, though an investigation of whether or not the shingles had self-sealed was also needed.

Weather: Wind damage can happen to any asphalt shingle roof in severe weather conditions. However if shingles are not properly nailed, shingles are far more likely to blow off of the roof in even a modest windstorm.

Proper roof shingle nailing: Roofing product manufacturers are careful to specify where shingle nails should be placed in each shingle and the number of nails required. These specifications may vary by shingle type and building location, with more nails specified for high-wind areas such as asphalt shingle roofs applied in coastal areas.

Just How Important is Nailing in Roof Shingle Wind Damage Prevention?

James A. Skees, PE

High Nailing Roof Shingles

When Hurricane Ike turned east after landfall in Texas in September 2008 and tracked up the Ohio River Valley, we had thousands of wind damage claims. I looked at several hundred. All of them I inspected were shingles that were improperly nailed. Most of the missing and torn shingles were nailed above the sealing strips.

Pneumatic Roof Nailer Pressure Settings

Another common nailing issue that leads to unnecessary wind damage is over-driving the nails, most often when pneumatic nailers are used.

Perhaps the most common cause of shingle blow-off in storms is improper or inadequate nailing by the roofing installer.

I don't remember a single wind damage claim where the nails were in the proper location and driven flush with the surface of the shingles. The instructions are usually printed on the packaging, complete with diagrams. In both English and Spanish.

With the compressor set too high, the heads cut through the fabric of the shingle, basically leaving the shingles unattached to the roof.

Another discussion of shingle nailing errors and omissions is at Mr. Skees' comments about LADDERING & STAIR STEPPING SHINGLES

Follow the Manufacturer's Shingle Nailing & Placement Instructions

Commentary: D Friedman

On a wood shingle failure where all of the shingles were improperly offset the roofer was trying to bluff his way through, insisting that his work was absolutely to spec and correct and in accordance with the manufacturer's instructions. A pile of swept-up debris remained in the courtyard (this was a big expensive roof job).

Taking the roofer aside, away from the client (and from unnecessary embarrassment) I reached into the pile and pulled out one of the inserts from the manufacturer that showed the shingle offset pattern they wanted and the nailing pattern - which was totally different from what he had used. The result was cursing and fist shaking and stomping off the job. The client, however, read and recognized the significance of the manufacturer's instructions.

As Skees points out

The shingle nailing instructions are usually printed on the packaging, complete with diagrams. In both English and Spanish.

Reading the instructions doesn't take but a moment, and it would be a great idea.

Components of roof shingle wind damage resistance

Asphalt shingle wind resistance combines several factors including the effectiveness of the glue strips on the shingle backs which adhere the shingle courses against wind-uplift, roof pitch, roof orientation with respect to prevailing winds, and importantly, proper shingle nailing patterns.

Not only must nails be properly placed and spaced, improper nailing itself, such as driving a nail through the shingle, leaving a nail sticking up to cut a shingle above, or using a roofing stapler improperly leaving cocked staples or shingle-cutting staples will all encourage shingles to fly away with the wind.

If an new roof has the bad luck to encounter a severe wind storm shortly after asphalt shingles have been installed, it is possible that the shingles will blow off of the roof because their self-sealing tabs have simply not had time (or warm enough weather or enough sun) to adhere.

For FEMA advice on wind damage resistant construction of roofing, see "Asphalt Shingle Roofing for High Wind Regions, Home Builders' Guide to Coastal Construction", FEMA 499, August 2005, Technical Fact Sheet No. 20.

Roofing Shingle Glue Strip or Glue Tab Adhesion Failure as Contributor to Wind Damage to Asphalt Shingle Roofs

Adhesive spots on an asphalt roof shingle (C) Daniel Friedman

Our photo (left) shows a typical 3-tab asphalt roof shingle (this one is made by GAF™). The shiny black strips form the "glue line" on the shingle. This adhesive is intended to bond to the three tabs of the next shingles nailed atop of this one when the roof is later warmed by sunlight.

On occasions, particularly during high wind conditions such as hurricanes, defective glue strips or adhesive strips on the underside of asphalt shingles may not provide sufficient adhesion, or if the shingles were not properly handled and the glue strip was dirty, an adhesion failure can lead to failure of the shingle tabs to adhere to the nailed-down header of the shingle above. In this case exposure to high winds can cause shingles to tear or blow off of the roof, increasing the degree of water damage inside the building when such winds are accompanied by rain.

In most climates exposure to even a few weeks of normal sunlight will cause the glue tabs on the under-side of asphalt roof shingles to soften and adhere to the surface below.

We discuss the function of asphalt shingle adhesive strips, handling the protective cellophane strip, and shingle uplift wind damage prevention in more detail below.

Extra Sealant Recommended for Shingle Wind-Damage Resistance

As detaile at ASPHALT SHINGLE INSTALLATION stated in the printed text: Best Practices Guide to Residential Construction:

Figure 2-7 Shingle Sealing Details (C) Wiley and Sons, S Bliss

 

In cold climates, the asphalt shingle sealant strip may not set up properly and may require manual sealing.

For three-tab shingles, place two quarter-size spots of plastic roof cement under the lower corners of each tab (as shown in Figure 2-7).

With laminated shingles, place four to six quarter-sized dots, spaced evenly, about one inch above the bottom of the overlapping shingle.

Our page top photo shows the standard sealant strips found on asphalt shingles, in this case a GAF® product we photographed at a Home Depot® store.

Here is what the GAF Materials Corporation, Grand Timberline™ Premium Architectural Shingle Application Instructions say about the glue strips and cellophane. You'll note that we are to leave the cellophane in place, but if site conditions (high wind) require immediate shingle sealing, an extra step, using additional shingle tab adhesive, is permitted.

WIND RESISTANCE/HAND SEALING: These shingles have a special thermal sealant that firmly bonds the shingles together after application when exposed to sun and warm temperatures. Shingles installed in Fall or Winter may not seal until the following Spring. If shingles are damaged by winds before sealing or are not exposed to adequate surface temperatures, or if the self sealant gets dirty, the shingles may never seal. Failure to seal under these circumstances results from the nature of self-sealing shingles and is not a manufacturing defect.

To insure immediate sealing, apply 4 quarter-sized dabs of shingle tab adhesive on the back of the shingle 1" (25mm) and 13" (330mm) in from each side and 1" (25mm) up from bottom of the shingle. Press shingle firmly into the adhesive. For maximum wind resistance along rakes, cement shingles to underlayment and each other in a 4" (102mm) width of asphalt plastic roof cement.

NOTE: Excess tab adhesive can cause blistering of the shingle. [The company is referring to the use of additional roof shingle adhesive, not the factory-applied glue strip. Also see BLISTERS on ASPHALT SHINGLES -- InspectAPedia]. The film strips on the back of each shingle are to prevent sticking together of the shingles while in the bundle and to keep dirt and debris out of the adhesive material so that after installation the adhesive will work. Their removal is NOT required during application.

Should the Cellophane Strip on the Back of Asphalt Shingles be Pulled Off?

Cellophane strip on a shingle back (C) Daniel FriedmanOur photo (left) shows the cellophane strip found on the back or "down"
side of a typical asphalt roof shingle. This one is a GAF™ product.

No: In answer to a common reader question, not normally: according to roofing manufacturers, it is not required to remove the cellophane strip on the back of roof shingles before they are nailed. Below we quote from a major manufacturer's instructions.

Yes: as we discuss in more detail below, experts familiar with wind damaged roofs (in coastal areas exposed to hurricanes and in other high-wind areas) previously recommended both the removal of the cellophane strip and the installation of double-sticky-sided roofing adhesive mastic tape or roof cement under shingle tabs at the time of asphalt roof shingle installation.

As Cramer reported in 2009 (see "More on the "yes" answer" just below, currently asphalt shingles sold in high wind areas adhere and cannot be pulled apart by wind (nor hand).

Certainly if you wait to remove the cellophane strip until the moment that the shingle is about to be nailed, taking it off will do no harm, and it may speed the adhesion between shingles that is intended to resist wind blow-off of roof shingles. We suspect that few professional roofers will add to their roofing time and cost by taking a step that is not recommended by the product manufacturer.

More on the "no" answer to removing roof shingle cellophane strips

Shingle sealant cellophane strip (C) Daniel FriedmanAsphalt roof shingle manufacturers recommend that installers leave that piece of cellophane in place. It does not need to be removed before, during, or after roof shingle installation.

Our photograph of the cellophane strip in place on the underside of an asphalt roof shingle (left) clearly shows that the shingle manufacturer says "Do Not Remove This Tape".

The cellophane tape on the back side of asphalt roof shingles is intended to prevent the glue strips from becoming activated prematurely, in storage or shipping, and equally important, to keep the glue-area clean during the roof installation process: jobsite debris (sawdust, dirt) can prevent the sealant from adhering.

Once the roof is installed the heat from sunlight will activate the sealing mastic through the cellophane. It does not need to be removed as part of the roofing process.

Actually, trying to remove the strip after installation might also risk damaging the shingle since you'd have to run along the roof slope lifting nailed-down shingle tabs to try to (unnecessarily) pull off the cellophane - risking tearing shingles and causing also extra foot traffic wear.

More on the "yes" answer to removing roof shingle cellophane strips.

One of our readers, Leonard Wheeler, reported that independent analysis of wind damaged roofs concluded that "... many shingles and attachment adhesives used were not adequate for the wind speeds that occurred. The most common failure mode was lifting of the tabs due to failure of the self-seal adhesive, and subsequent tearing of the shingles at the fasteners (Smith, 1994)." Our associate, Mark Cramer, a Florida home inspector and educator in the field, reported that houses suffering damage during Hurricane Andrew were generally those not built to code, and that code-built homes survived the hurricane with minimal damage. Mr. Cramer provides this update:

Asphalt roof shingles sold today (2009) in high wind zones are totally different from what we used in the early 90’s. Forget the number of nails also, four is fine for most shingles used today. The problem was not number of nails but failure of adhesion. Today’s high wind shingles can’t be pulled apart once they seal.

Other measures to reduce water damage to buildings in coastal or high wind areas include use of roof flashing tape or strips of ice-and-water-shield type products over the butt joints between sections of plywood or OSB roof decking. The presence of roofing felt under shingles won't prevent roof leaks after shingles are installed, since the shingle nails will have made thousands of penetrations in that membrane.

A Forensic Engineer's View on Cellophane Strips on Asphalt Roof Shingles

The only time the cellophane strip protects the seal strips is while they are still in the package.

James A. Skees, PE

I am a forensic engineer who works for insurance companies. Occasionally I find a limited number of shingles on a roof did not seal because the cellophane strips have attached to the seal strips instead of staying on the underside of the shingles in the package. Let me try to explain that better.

The cellophane strips are attached to the center of the undersides of the shingles at the factory. The seal strips are on the top side at the center of the shingles.

The only time the cellophane strip protects the seal strips is while they are still in the package. Occasionally stacks of shingles are left out in the sun before they are installed, sometimes while at the distribution center, sometimes at the factory, sometimes on the truck that delivers them, sometimes in stacks in the yard before they are installed, and even sometimes across the roof before the roofers open the packages.

In those cases (you see above they can be many cases), the solar radiation can activate the sealing strip adhesive on the top shingle or two or maybe even three, and the cellophane attaches to the top side of the shingle covering the adhesive when the shingles are taken out of the bundle.

Most of the cellophane strips have the instructions not to remove printed on the surface. However, it will be printed in reverse when it sticks to the seal strip (since it is intended to be read from the bottom). However, to most of us that read English it still admonishes that it not be removed, even if it is printed backwards.

With the cellophane in place covering the sealant, the shingles installed over those individual two or three (per bundle) will never seal. This leads to blow-off failure more often than you would think.

I find several like this every year and there may be as many as ten to 15 complete missing shingles on a single roof because of the cellophane sticking to the seal strips.

That is usually enough to put the insurance company on the hook for an entire roof that somebody installed incorrectly. - James A. Skees, PE

Opinion on When to Remove Cellophane Strips on Asphalt Shingles -DF

Based on the above our opinion is that you may leave the cellophane strips in place on the shingle back surface (which is ok with the manufacturer) so long as the strip is intact and in its original position.

But when installing an asphalt shingle roof if you encounter cellophane strips that have already come loose, you may as well remove them and dispose of them off of the roof.

Do not leave loose cellophane strips nor any other extraneous debris on a roof, especially when installing new roof shingles as those materials may interfere with proper roof tab sealing and may lead to future increased shingle blow-off in windy conditions.

About deliberately pulling off all of the tabs: if you are in a high wind area and are going to be adding additional sealant anyway, this step is probably unnecessary and is not specified by the manufacturer.

Earlier, in the 1990's we were concerned with excessive bonding between shingles that combined with a lack of tear resistance to lead to premature roof failures due to thermal splitting. It's fair to add, however, that the root cause of that problem was a specification that led to inadequate tear resistance, not an innate fault with shingle tab bonding. See CRACKS in FIBERGLASS SHINGLES

Other Examples of Wind Damaged Shingle Roofs

Wind damaged roof shingles (C) Daniel Friedman Wind damaged roof shingles (C) Daniel Friedman

The photographs here include examples of improperly or inadequately-nailed shingles which blew off in modest windstorms of far less than hurricane strength. In the first photograph below, our correspondent has laid-out shingles retrieved after the storm, showing the location and pattern of nail holes in each shingle - clear evidence of just how they were nailed. Our ridge cap shingle loss (above left) is plainly due to wind damage. The shingles falling off of the barn roof (above right) appear due to a combination of wind damage and possibly inadequate nailing.


  • Workmanship: Fasteners/Nailing Problems
    lead to holes or wind blow-off. Roofing manufacturers provide recommendations for the type of shingle fastener (nails are recommended), the type of roofing nail, and the length of roofing nail required. Yes, it is proper for roofing nails to penetrate through the roof decking so that the tips of the nails are visible inside. This is particularly important where 1/2" roofing plywood or OSB decking are used (as opposed to thicker roof decking materials). Here is a representative example comment on roofing nails from the GAF Materials Corporation Grand Timberline™ Premium Architectural Shingle Application Instructions:


    FASTENERS: Use of nails is recommended. Use only zinc coated steel or aluminum, 10-12 gauge, barbed, deformed or smooth shank roofing nails with heads 3/8" (10mm) to 7/16" (12mm) in diameter. Fasteners should be long enough to penetrate at least 3/4" (19mm) into wood decks or just through the plywood decks. Fasteners must be driven flush with the surface of the shingle. Over driving will damage the shingle. Raised fasteners will interfere with the sealing of the shingles.

    Experts discussing measures to reduce asphalt roof shingle blow-off in coastal or other high-wind areas recommend against using roofing staples to install shingles.

  • Workmanship: Fasteners/Nailing Problems lead to holes or wind blow-off. Notice that not only has one shingle already fallen or been blown off of the roof, but its neighbors are sliding down. Diagnosis from a photograph is questionable but there appears to be a nailing problem here.


  • Workmanship: Installation Pattern Problems:Laddering [Photo: Carl Gerosa, New Rochelle, NY.]




  • Workmanship, condition of roof deck, roof flashing, roofing felt underlayment: Flashing and underlayment problems: Here is a representative example comment on the use of roofing felt underlayment and roof decking condition, from the GAF Materials Corporation Grand Timberline™ Premium Architectural Shingle Application Instructions:

    UNDERLAYMENT: Underlayment beneath shingles has many benefits, including preventing wind driven rain from reaching the interior of the building and preventing sap in some wood decking from reacting with asphalt shingles. Underlayment is also required by many code bodies. Where an underlayment is to be installed, use a breather-type underlayment such as GAF Shingle-Mate® underlayment.

    ROOF DECKS: Wood decks must be well-seasoned, supported, and tightly-constructed with maximum 6" (152mm) wide lumber, having adequate nail-holding capacity and a smooth surface. Plywood decking as recommended by The Engineered Wood Association is acceptable. Where a Class A rating is required over decks less than 15/32" thick, an underlayment is required. Do not fasten shingles directly to insulation or insulated deck unless authorized in writing by GAF. Roof decks and existing surfacing material must be dry prior to application of shingles.

  • Workmanship: Improper materials/roof-slope problems - installing shingles on low-slope roofs, for example.
  • Holes and nail-pops in shingle roofs, mechanically damaged roof shingles.
  • Choice of roofing, shingle type, underlayment, and roof decking materials: In a 2005 article Paul Fisette cited Mitrani who, more than a decade earlier, concluded that in areas of coastal high winds and storms, OSB was an inferior roof decking product to plywood. Opinion among Florida consultants currently is that OSB is fine and performs as well as plywood. -- Cramer (personal communication 4/1/09).

In discussing wind damage to roofing with your insurance adjuster or roofing contractor, be sure to review the details of original and replacement shingle installation as this can give evidence about the underlying cause of roof failure as well as informing you of how to avoid roof shingle blow-off in the future.

For FEMA advice on wind damage resistant construction of roofing, see "Asphalt Shingle Roofing for High Wind Regions, Home Builders' Guide to Coastal Construction", FEMA 499, August 2005, Technical Fact Sheet No. 20.

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ROOFING INSPECTION & REPAIR

AGE OF ROOFING
ALUMINUM ROOFING
AMERICAN CEMWOOD ROOFING
ARCHITECTURE & BUILDING COMPONENT ID

ASBESTOS IDENTIFICATION IN buildings
ASBESTOS CEMENT & FIBER CEMENT ROOFING

ASPHALT ROOF SHINGLES
  ASPHALT SHINGLE DEFINITIONS
  ASPHALT SHINGLE FAILURE TYPES
  ASPHALT SHINGLE INSTALLATION
  ASPHALT SHINGLE LIFE / WEAR FACTORS
  ASPHALT SHINGLE PROPERTIES
  ASPHALT SHINGLE RE-ROOF GUIDE
  ASPHALT SHINGLE UNDERLAYMENT SPECS
  ASPHALT SHINGLE VALLEY FLASHING
  ASPHALT SHINGLES on VERY STEEP ROOFS
  ALGAE, FUNGUS, LICHENS, MOSS COMPARED
  ALGAE STAINS ON ASPHALT ROOF SHINGLES
  ALGAE STAIN TEST METHODS
  ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES
  BLACK STAIN REMOVAL & PREVENTION
  BLISTERS on ASPHALT SHINGLES
  CRACKS in FIBERGLASS SHINGLES
  CUPPING ASPHALT SHINGLES
  CURLING ASPHALT SHINGLES
  EARLY ASPHALT SHINGLE FAILURE
  EXTRACTIVE BLEEDING on SHINGLES
  FISHMOUTHING ASPHALT SHINGLES
  GRANULE LOSS from SHINGLES
  HAIL DAMAGED SHINGLES
  LADDERING & STAIR STEPPING SHINGLES
  LIFE / WEAR FACTORS in SHINGLES
  MECHANICAL DAMAGE of SHINGLES
  MOSS & LICHENS on SHINGLES
  ORGANIC FELT SHINGLE DEFECTS
  SPLICE DEFECTS on ASPHALT SHINGLES
  STAINS on ROOF SHINGLES
  WHAT ARE ASPHALT SHINGLES
  WIND DAMAGE to ROOFS

ASBESTOS ROOFING / SIDING DUST
ATTIC LEAKS, CONDENSATION & ATTIC MOLD
ATTIC VENTILATION

BEST CONSTRUCTION PRACTICES GUIDE
BEST ROOFING PRACTICES
BUILDING SAFETY HAZARDS GUIDE
BUILT UP ROOFS

CEMWOOD ROOFING
CERTIFICATIONS for ROOFING CONTRACTORS

CHIMNEY INSPECTION & REPAIRS
Chimney Flashing Mistakes & Leaks

CHOOSING A ROOFING CONTRACTOR

CLAY TILE ROOFING
  Clay Roofing Tile Types
  CLAY TILE ROOF STYLES, DESIGNS
  CLAY TILE ROOF SPECIFICATIONS
  CLAY TILE ROOF SLOPE, DECK & UNDERLAY
  CLAY TILE ROOF BATTENS & STACKING
  CLAY TILE ROOF CONNECTIONS
  CLAY TILE WIND & SEISMIC CONNECTORS
  CLAY TILE EAVES, HIP & RAKE DETAILS
  FLASHING, CLAY TILE ROOFS
  CLAY TILE ROOF DAMAGE & WEAR
  ROOFING TILE SHAPES & PROFILES
  CLAY TILE ROOF SUPPLIERS
CLAY, CONCRETE, FIBER CEMENT ROOF TILES
COLD WEATHER ROOF TROUBLE

CONCRETE ROOFING
COOLING LOAD REDUCTION by ROOF VENTS
CORRUGATED ROOFING
COPPER ROOFING

DEBRIS STAINING on ROOFS

DECKS, ROOFTOP CONSTRUCTION
DEFINITIONS of ENGINEERED WOOD OSB LVL etc
DISASTERS: BUILDING INSPECTION & REPAIR SAFEY
  Hurricane or Storm Flooding
  Hurricane Safety Preparation
  Hurricane Damage Prevention
  Wildfire Damage Prevention
  Windstorm Damage Prevention

EARLY ROOF FAILURE DIAGNOSTIC QUESTIONS
ENERGY SAVINGS in buildings
FELT UNDERLAYMENT REQUIREMENTS

FIBER CEMENT & FIBERBOARD ROOFING

FIRE RATINGS for ROOF SURFACES
FIRE RETARDANT PLYWOOD

FLASHING, ASPHALT SHINGLE VALLEYS
FLASHING, CLAY TILE ROOFS
FLASHING MEMBRANES PEEL & STICK
FLASHING for METAL ROOFS
FLASHING ROOF WALL DETAILS
FLASHING ROOF-WALL SNAFU
FLASHING SIDING DETAILS
FLASHING WALL DETAILS
FLASHING WOOD ROOF DETAILS

FLAT ROOF MOISTURE & CONDENSATION

GALVANIC SCALE & METAL CORROSION
Green House or Solarium Roof Leaks
GUTTERS & DOWNSPOUTS

HAIL DAMAGED SHINGLES
HEAT TAPES & CABLES on Roofs for Ice Dams
HOT ROOF DESIGNS: Un-Vented Roof Solutions
HOUSEWRAP INSTALLATION DETAILS
HUMIDITY LEVEL TARGET

ICE DAM PREVENTION
  Ice Dams: Comparing Two Houses
INSULATION IDENTIFICATION GUIDE
INSULATION INSPECTION & IMPROVEMENT

LEAD POISONING HAZARDS GUIDE
LEAKY ROOF DIAGNOSIS & REPAIR
LEED GREEN BUILDING CERTIFICATION
LOW SLOPE ROOFING

MASONITE WOODRUF FIBERBOARD ROOFING

MEMBRANE & SINGLE PLY ROOFS

METAL ROOFING
MODIFIED BITUMEN ROOFING

NOISE CONTROL for ROOFS

NOISE / SOUND DIAGNOSIS & CURE

PLASTIC ROOFING TYPES

ROLL ROOFING, ASPHALT
ROOF ARCHITECTURAL STYLES - PHOTO GUIDE
ROOF CLEANING RECOMMENDATIONS
ROOF DORMER TYPES - PHOTO GUIDE
ROOF INSPECTION SAFETY & LIMITS
ROOF SLOPE DEFINITIONS

ROOF VENTILATION SPECIFICATIONS
ROOF VENTING ENERGY SAVING DETAILS

ROOFING FELT UNDERLAYMENT REQUIREMENTS
ROOFING MATERIALS, Age, Types

ROOF NOISE TRANSMISSION
ROOFING TILE SHAPES & PROFILES

ROOFING UNDERLAYMENT BEST PRACTICES

SADDLE CONSTRUCTION at CHIMNEYS
SLATE ROOF INSPECTION & REPAIR
SNOW GUARDS on SLATE & METAL ROOFS
SOD ROOFING

STAIN & BIODETERIORATION AGENT CATALOG
STAINS on buildings - QUICK GUIDE
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
STAIN DIAGNOSIS on ROOFS
STAIN DIAGNOSIS on STONE

STANDARDS for ROOFING
STONE CLEANING METHODS
STONE ROOFING
STRESS SKIN INSULATED PANELS

TEST LABS - ROOF SHINGLE
THATCH ROOFING
THERMAL EXPANSION of MATERIALS
THERMAL MASS in buildings

TILE ROOFING

TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof

UNDERLAYMENT REQUIREMENTS on ROOFS

WALK-ON ROOF SURFACES
WARRANTIES for ROOF SHINGLES
  SHINGLE CLASS ACTION
  REPORTING SHINGLE FAILURES
  ROOF FAILURE REPORT FORM
  ASBESTOS CEMENT & FIBER CEMENT ROOFING
  CEMWOOD ROOFING
  MASONITE WOODRUF FIBERBOARD ROOFING
  ROOFING COMPANIES CONTACT INFO

WIND DAMAGE to ROOFS

WORKMANSHIP & ROOF DAMAGE

ZINC METAL ROOFING
  • Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. (727) 595-4211 mark@BestTampaInspector.com
  • Hankey and Brown home inspectors, Eden Prairie, MN, technical review by Roger Hankey, prior chairman, Standards Committee, American Society of Home Inspectors - ASHI. 952 829-0044 - hankeyandbrown.com
  • Arlene Puentes, a licensed home inspector, educator, and building failures researcher in Kingston, NY.
  • Thanks to Carl Gerosa, New Rochelle, NY for photos of cupping asphalt roof shingles. Carl J. Gerosa is an ASHI Certified home inspector who can be reached at 914-833-2900.
  • Thanks to Leonard Wheeler, Retired DCA Disaster Assessment Engineer for Hurricane Andrew, for questions leading to clarification on the proper handling of asphalt shingle glue strip protective cellophane during roof installation 3/29/09.
  • Thanks to James A. Skees, PE, President and Sr. Forensic Engineer, OnTheRock Engineering, LLC, 604 W. Jefferson Street, LaGrange, KY 40031 502-225-6203 FAX 225-6204, for commenting on the roof cellophane strip problem, on wind damage to roof shingles, shingle blow off, improper shingle nailing, and roof shingle laddering underlying defects, August 2010. Mr. Skees is a forensic engineer who works for insurance companies. Mr. Skees can also be reached by email at jimskees@ontherockeng.com
    The company has published online a sample Tornado Report
    "Residential Wind Damage Evaluation", Wind Damage Sample, found at http://www.ontherockeng.com/Sample%20Tornado%20Report.pdf
  • "Asphalt Shingle Roofing for High Wind Regions, Home Builders' Guide to Coastal Construction", FEMA 499, August 2005, Technical Fact Sheet No. 20 [To recommend practices for installing asphalt roof shingles that will enhance wind resistance in high-wind, coastal regions.]
  • GAF Materials Corporation, Grand Timberline Premium Architectural Shingle Application Instructions.
    http://www.gaf.com/Content/Documents/20573.pdf discusses the requirements for successful asphalt shingle installation including the condition of the roof deck, the use of roofing felt underlayment, the selection of roofing nails by type and length and penetration of the roof decking, and the role of glue strips on the back side of asphalt roof shingles.
  • Roofing The Right Way, Steven Bolt, McGraw-Hill Professional; 3rd edition (November 1, 1996), ISBN-13: 978-0070066502, p. 350 for one of many citations on this point.
  • "Hurricane Damage to Residential Structures: Risk and Mitigation", Jon K. Ayscue, The Johns Hopkins University, Baltimore, Maryland, published by the Natural Hazards Research and Applications Information Center, Institute of Behavioral Science, University of Colorado, November 1996. Abstract:
    "Property damage and loss from hurricanes have increased with population growth in coastal areas, and climatic factors point to more frequent and intense hurricanes in the future. This paper describes potential hurricane hazards from wind and water. Damage to residential structures from three recent intense hurricanes - Hugo, Andrew, and Iniki - shows that wind is responsible for greater property loss than water. The current state-of-the-art building technology is sufficient to reduce damage from hurricanes when properly applied, and this paper discusses those building techniques that can mitigate hurricane damage and recommends measures for mitigating future hurricane damage to homes." - online at www.colorado.edu/hazards/publications/wp/wp94/wp94.html
  • "Evaluating OSB for Coastal Roofs," Paul Fisette, Coastal Contractor, Winter 2005, online at coastalcontractor.net/pdf/2005/0501/0501eval.pdf . Fisette cites: "Jose Mitrani, a civil engineer and professor at Florida. International University in Miami, was ... Florida’s official damage assessment team. ... After Hurricane Andrew, Florida code advisers ruled OSB sheathing inferior to plywood."

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

  • Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
  • Home Reference Book - Carson Dunlop The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 2010, $69.00 U.S., is available from Carson Dunlop. The Home Reference Book is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. InspectAPedia.com ® author/editor Daniel Friedman is a contributing author. Field inspection worksheets are included at the back of the volume.
  • Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
  • Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
  • The Journal of Light Construction has generously given reprint permission to InspectAPedia.com for this article. All rights and contents are ©Journal of Light Construction and may not be reproduced in any form.
  • Architectural elements: the technological revolution: Galvanized iron roof plates and corrugated sheets; cast iron facades, columns, door and window caps, ... (American historical catalog collection), Diana S Waite, available used out of Amazon.
  • Asphalt Roofing Residential Manual,
  • Building Pathology, Deterioration, Diagnostics, and Intervention, Samuel Y. Harris, P.E., AIA, Esq., ISBN 0-471-33172-4, John Wiley & Sons, 2001 [General building science-DF] ISBN-10: 0471331724 ISBN-13: 978-0471331728
  • Building Pathology: Principles and Practice, David Watt, Wiley-Blackwell; 2 edition (March 7, 2008) ISBN-10: 1405161035 ISBN-13: 978-1405161039
  • Built-Up Roof Systems, Manual, C.W. Griffin, Mcgraw-Hill (Tx); 2nd edition (July 1982), ISBN-10: 0070247838, ISBN-13: 978-0070247833
  • Concrete Folded Plate Roofs, C. Wilby PhD BSc CEng FICE FIStructE (Author), Butterworth-Heinemann, 1998, ISBN-10: 0340662662, ISBN-13: 978-0340662663
  • Concrete Shell Roofs, C. Wilby PhD BSc CEng FICE FIStructE (Author),
  • Concrete Dome Roofs (Longman Concrete Design and Construction Series),
  • Concrete Roofing Tile, History of the, Batsford, 1959, AISN B000HLLOUC (availble used)
  • Copper Roofing, by CDA
  • Copper Roofing, Master specifications for copper roofing and sheet metal work in building construction: Institutional, commercial, industrial, I.E. Anderson, 1961 (hard to find)
  • Corrugated Iron, Building on the Frontier, Simon Holloway
  • Green Roof Plants: A Resource and Planting Guide, Edmund C. Snodgrass, Lucie L. Snodgrass, Timber Press, Incorporated, 2006, ISBN-10: 0881927872, ISBN-13: 978-0881927870. The text covers moisture needs, heat tolerance, hardiness, bloom color, foliage characteristics, and height of 350 species and cultivars.
  • Green Roof Construction and Maintenance, Kelley Luckett, McGraw-Hill Professional, 2009, ISBN-10: 007160880X, ISBN-13: 978-0071608800, quoting: Key questions to ask at each stage of the green building process Tested tips and techniques for successful structural design Construction methods for new and existing buildings Information on insulation, drainage, detailing, irrigation, and plant selection Details on optimal soil formulation Illustrations featuring various stages of construction Best practices for green roof maintenance A survey of environmental benefits, including evapo-transpiration, storm-water management, habitat restoration, and improvement of air quality Tips on the LEED design and certification process Considerations for assessing return on investment Color photographs of successfully installed green roofs Useful checklists, tables, and charts
  • Handbook of Building Crafts in Conservation, Jack Bower, Ed., Van Nostrand Reinhold Company, NY 1981 ISBN 0-442-2135-3 Library of Congress Catalog Card Nr. 81-50643.
  • Historic Preservation Technology: A Primer, Robert A. Young, Wiley (March 21, 2008) ISBN-10: 0471788368 ISBN-13: 978-0471788362
  • Historic Slate Roofs : With How-to Info and Specifications, Tina Skinner (Ed), Schiffer Publishing, 2008, ISBN-10: 0764330012 , ISBN-13: 978-0764330018
  • Low Slope Roofing, Manual of, 4th Ed., C.W. Griffin, Richard Fricklas, McGraw-Hill Professional; 4 edition, 2006, ISBN-10: 007145828X, ISBN-13: 978-0071458283
    • Roof failure causes in depth (and specific methods for avoiding them)
    • Roof design fundamentals and flourishes, based on voluminous industry research and experience
    • New technologies and materials -- using them safely and correctly
    • Comprehensive coverage of all major roofing systems pecifications, inspection, and maintenance tools for roofing work
  • Metal Roofing, an Illustrated Guide, R.A. Knowlton , [metal shingle roofs],
  • Patio Roofs, how to build, Sunset Books
  • Problems in Roofing Design, B. Harrison McCampbell, Butterworth Heineman, 1991 ISBN 0-7506-9162-X (available used)
  • Roofing The Right Way, Steven Bolt, McGraw-Hill Professional; 3rd Ed (1996), ISBN-10: 0070066507, ISBN-13: 978-0070066502
  • Slate Roofs, National Slate Association, 1926, reprinted 1977 by Vermont Structural Slate Co., Inc., Fair Haven, VT 05743, 802-265-4933/34. (We recommend this book if you can find it. It has gone in and out of print on occasion.)
  • Roof Tiling & Slating, a Practical Guide, Kevin Taylor, Crowood Press (2008), ISBN 978-1847970237,
    If you have never fixed a roof tile or slate before but have wondered how to go about repairing or replacing them, then this is the book for you. Many of the technical books about roof tiling and slating are rather vague and conveniently ignore some of the trickier problems and how they can be resolved. In Roof Tiling and Slating, the author rejects this cautious approach. Kevin Taylor uses both his extensive knowledge of the trade and his ability to explain the subject in easily understandable terms, to demonstrate how to carry out the work safely to a high standard, using tried and tested methods. 
    This clay roof tile guide considers the various types of tiles, slates, and roofing materials on the market as well as their uses, how to estimate the required quantities, and where to buy them. It also discusses how to check and assess a roof and how to identify and rectify problems; describes how to efficiently "set out" roofs from small, simple jobs to larger and more complicated projects, thus making the work quicker, simpler, and neater; examines the correct and the incorrect ways of installing background materials such as underlay, battens, and valley liners; explains how to install interlocking tiles, plain tiles, and artificial and natural slates; covers both modern and traditional methods and skills, including cutting materials by hand without the assistance of power tools; and provides invaluable guidance on repairs and maintenance issues, and highlights common mistakes and how they can be avoided. The author, Kevin Taylor, works for the National Federation of Roofing Contractors as a technical manager presenting technical advice and providing education and training for young roofers.
  • The Slate Roof Bible, Joseph Jenkins, www.jenkinsslate.com, 143 Forest Lane, PO Box 607, Grove City, PA 16127 - 866-641-7141 (We recommend this book).
  • Slate Roofing in Canada (Studi4es in archaeology, architecture, and history),
  • Smart Guide: Roofing: Step-by-Step Projects, Creative Homeowner (Ed), 2004, ISBN-10: 1580111491, ISBN-13: 978-1580111492
  • Solar heating, radiative cooling and thermal movement: Their effects on built-up roofing (United States. National Bureau of Standards. Technical note), William C Cullen, Superintendent of Documents, U.S. Govt. Print. Off (1963), ASIN: B0007FTV2Q
  • Tile Roofs of Alfred: A Clay Tradition in Alfred NY
  • "Weather-Resistive Barriers [copy on file as /interiors/Weather_Resistant_Barriers_DOE.pdf ] - ", how to select and install housewrap and other types of weather resistive barriers, U.S. DOE
  • Wood Shingle Roofs, Care and Maintenance of wood shingle and shake roofs (EC), Stanley S. Niemiec (out of print)
  • ...
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