Question? Just ask us!
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
InspectAPedia ® Home
ROOFING INSPECTION & REPAIR
AGE OF ROOFING
AMERICAN CEMWOOD ROOFING
ARCHITECTURE & BUILDING COMPONENT ID
ASBESTOS IDENTIFICATION IN buildings
ASBESTOS & FIBER CEMENT ROOFING
ASBESTOS MATERIAL REGULATIONS
ASPHALT ROOF SHINGLES
ROOF ICE DAM LEAKS
BEST CONSTRUCTION PRACTICES GUIDE
BEST ROOFING PRACTICES
BEST CONSTRUCTION PRACTICES GUIDE
BEST ROOFING PRACTICES
BUILDING SAFETY HAZARDS GUIDE
BUILT UP ROOFS
CATHEDRAL CEILING INSULATION
CATHEDRAL CEILING VENTILATION
CERTIFICATIONS for ROOFING CONTRACTORS
CHIMNEY INSPECTION & REPAIRS
CHIMNEY FLASHING Mistakes & Leaks
CHOOSING A ROOFING CONTRACTOR
CLAY TILE ROOFING
CLAY, CONCRETE, FIBER CEMENT TILE INSTALLATION
COLD WEATHER ROOF TROUBLE
COOLING LOAD REDUCTION by ROOF VENTS
DEBRIS STAINING on ROOFS
DECKS, ROOFTOP CONSTRUCTION
DEFINITIONS of ENGINEERED WOOD OSB LVL etc
DISASTERS: BUILDING INSPECTION & REPAIR
DISPUTE RESOLUTION on ROOF JOB PROBLEMS
ENERGY SAVINGS in buildings
EPDM, RUBBER, PVC ROOFING
EPDM ROOF LEAK REPAIRS
EXTRACTIVE BLEEDING on SHINGLES
FELT UNDERLAYMENT REQUIREMENTS
FIBER-WOOD & FIBERBOARD ROOFING
FIRE RATINGS for ROOF SURFACES
FIRE RETARDANT PLYWOOD
FLASHING on BUILDINGS
FLASHING, ASPHALT SHINGLE VALLEYS
FLASHING, CHIMNEY Mistakes & Leaks
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 WINDOW 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
ROOF ICE DAM LEAKS
INSECT INFESTATION / DAMAGE
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
MODIFIED BITUMEN ROOFING
NOISE / SOUND DIAGNOSIS & CURE
NOISE CONTROL for ROOFS
PLASTIC ROOFING TYPES
PVC, EPDM, RUBBER ROOFING
ROLL ROOFING, ASPHALT
ROOF ARCHITECTURAL STYLES - PHOTO GUIDE
ROOF CLEANING RECOMMENDATIONS
ROOF COLOR RECOMMENDATIONS
ROOF DORMER TYPES - PHOTO GUIDE
ROOF INSPECTION SAFETY & LIMITS
ROOF JOB PROBLEMS, RESOLVING
ROOF LEAK DIAGNOSIS & REPAIR
ROOF NOISE TRANSMISSION
ROOF REPLACEMENT SNAFUs
ROOF SLOPE DEFINITIONS
ROOF VENTILATION SPECIFICATIONS
ROOFING FELT UNDERLAYMENT REQUIREMENTS
ROOFING MATERIALS, Age, Types
ROOFING TILE SHAPES & PROFILES
ROOFING UNDERLAYMENT BEST PRACTICES
RUBBER, EPDM, PVC ROOFING
SADDLE CONSTRUCTION at CHIMNEYS
SIDING TYPES, INSTALLATION, DEFECTS
SLATE ROOF INSPECTION & REPAIR
SNOW GUARDS & SNOW BRAKES
SOUND CONTROL in buildings
STAIN & BIODETERIORATION AGENT CATALOG
STAINS on & in BUILDINGS, CAUSES & CURES
STAINS on CONCRETE
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
STAIN DIAGNOSIS on ROOFS
STAINS on STONE, DIAGNOSE & CURE
STANDARDS for ROOFING
STONE CLEANING METHODS
STRESS SKIN INSULATED PANELS
TEST LABS - ROOF SHINGLE
Thermal Expansion Cracking of Brick
THERMAL EXPANSION of HOT WATER
THERMAL EXPANSION of MATERIALS
THERMAL IMAGING, THERMOGRAPHY
THERMAL IMAGING MOLD SCANS
THERMAL MASS in BUILDINGS
TREES & SHRUBS, TRIM OFF BUILDING
TRUSS UPLIFT, ROOF
TRUSSES, Floor & Roof
UNDERLAYMENT REQUIREMENTS on ROOFS
VENTILATION in BUILDINGS
WALK-ON ROOF SURFACES
WARRANTIES for ROOF SHINGLES
WALL CONSTRUCTION BARRIER vs CAVITY
WATER ENTRY in buildings
WIND DAMAGE to ROOFS
WINTERIZE A BUILDING
WOOD SHAKE & SHINGLE ROOFING
WORKMANSHIP & ROOF DAMAGE
ZINC METAL ROOFING
Building roofs: inspection, installation, diagnosis, repair & replacement guide: these articles provide in-depth un-biased articles about building roofing materials, installations, inspection, roof problem or roof leak diagnosis and repair, roof covering or shingle product failures, roof warranties, roofing and roof structure defects, roofing repairs, and all types of roof covering products.
Page top Photo: collapsed barn, Cooperstown, NY leaves only its roof in view - Daniel Friedman
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
Example topics discussed in our building roofing articles include asphalt roof failures including thermal splitting and other defects, causes and types of asphalt shingle roof leaks, shingle blow-offs and wind damage, shingle cracks, blisters, stains, thermal splitting, and other damage, Fire retardant plywood roof sheathing defects.
How to find and choose a roofing contractor, How to inspect roofs, Roofing product failures, class actions, warranty claims, Roofing repair methods, Roofing product sources for Residential and light commercial roofs, Slate roof inspection and repair methods. Our page top photo shows a current roof situation that deserves some thought..
Here is a quick comparison of common roofing materials. Our roofing inspection, diagnosis, repair and installation articles listed at left and below provide roof inspection, roof leak or problem diagnosis, roof installation, and roof repair information as well as details about the factors that affect the life of any roof. We include roof warranty and claim information and links to roofing product sources.
Summary of Definitions of Roof Slope Types: Flat, Low Slope, Steep Slope Roofs
The illustration at left, courtesy of Carson Dunlop & Associates, summarizes the ranges of roof pitch or slope for flat, low-slope or conventional or "steep slope" roofing.
Flat roof: 0-2" rise per foot of run
Low-Slope Roof: less than or equal to 3" rise per foot of run
Steep slope roof: 4" rise in 12 or more.
[Click to enlarge any image]
Details about how roof slope is measured or calculated along with examples of converting between angle, slope and grade are at ROOF SLOPE DEFINITIONS.
Roof Covering Fire Resistance or "Fire Ratings"
In the U.S. roof coverings are rated for their ability to resist fire and to avoid spreading fire if the building burns. Both UL 790 and ASTM E 108 fire classification tests use the same test methods.
Class "A" roof fire ratings mean that under the specifics of the UL (or ASTM) fire rating test definition, the roof is effective against severe fire exposure.
Class "B" roof fire ratings mean that the roof is effective against moderate fire exposure.
Class "C" roof fire ratings mean that the roof is effective against slight fire exposure only.
Details about roof fire resistance effectiveness and roof fire ratings are at FIRE RATINGS for ROOF SURFACES.
Continue reading at ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES or select a topic from the More Reading links shown below.
Suggested citation for this web page
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Questions & answers or comments about types of roofing materials, installation, inspection, diagnosis, repair, maintenance, & warranties
Question: Staining on building from roof shingles made from recycled tires?
There are no trees around the house. We live in New Jersey right on the bay. Our builder had the gutters washed, but the black stain could not be removed.
Also, upon further investigation, my husband found extra shingles stored under the eaves of our attic. To our surprise "Royal Roofing" was stamped on the inside of each shingle--not Eternit!
Are these two separate companies? The architect's notes indicated "Eternit" as the roofing tiles--now I'm confused. Unfortunately, he has passed away and his business was dissolved.
When I contacted Eternit in England via e-mail, they said that they never manufactured a roof tile made from "recycled" tires. That was exactly how our architect described the tiles to us! He was very excited about its reported durability and longevity. Once again, Daniel, I hope you can shed light on this dilemma! - M.
Reply: Bleed-out and run-down stains on the building vs. shingle life
I'd like to see sharp photos of your roof shingles in place, both the field of the roof and closeups of the shingles, and I'd certainly want to see photos of the surfaces and markings of the extra shingles you found in your attic so that we can more accurately identify and contact the manufacturer with follow-up questions.
I'm not sure that all of the black stains in your photos are due to the composition of your roof shingles, and it's common to see some black stains on the outer edges of white K-profile aluminum gutters even on asphalt shingle roofs. More about diagnosing building stains is at STAINS on & in BUILDINGS, CAUSES & CURES.
But if your roof shingles are bleeding out significant levels of black debris, in addition to needing to clean the building exterior, you ought to be able to avoid stains on other building surfaces by properly routing roof runoff into gutters and downspouts.
A second question that might arise is whether or not black runout stains from a roofing product are a sign of deterioration or reduced roof life. Certainly the manufacturers of plastic and composite roof shingles we list below all promise rather long-life warranties.
Your roof shingles may be a Canadian product: Royal Dura Shingles. But first let's correctly identify your shingles and then ask the manufacturer for an opinion and advice. "Royal" as a roofing name alone is a bit broad as you'll see from our references below, including manufacturer names, roofing company names, and several asphalt shingle product names including IKO Royal Estate shingle and GAF Royal Sovereign shingles.
"Royal Roofing" may be a company name or a shingle model produced by a company of a different name. In any case, Eternit, a company about which you asked us previously, produced fiber cement shingles and is separate from Royal Group Technologies who produce Dura slate roof shingles (see our company list below).
Several companies produce roofing shingles made from recycled materials, rubber, composites, plastics, including:
Question: How do I track down roof leaks and decide if leaks are active or inactive? Wet spots & black mold found during interior repairs after prior roof leaks and a new roof installation
We live in a condo building, four story, concrete structure with brick face.
We have had our flat, concrete roof repaired multiple times in the past few years. Last year the roof was sponge-y with water. We had repairs made in all areas as per a building inspector's advice, and a water expert's advice, except for some tuck pointing problems which were terribly expensive, and didn't look all that problematic . Also we installed roof vents.
This summer the roof is no longer sponge-y. It is solid. But the owners of the fourth (top) floor apartment are having interior work done and are discovering black mold and water/moisture coming in in the very areas they want to repair.
The roof LOOKS good, flashing and parapets are tight, caps on parapets are repaired and in good shape, roof surface (modified bitumen) has been sealed this summer and looks to be in good shape.
Is it possible this is still water percolating down from our concrete roof? Or should we be looking for new leaks?
Should we be calling yet another roofer? Or should we be waiting for the interior to be free of the old buildup of water which is still making its way down from the soggy, sponge-y roof we had last summer.
Thank you for any advice you can give us. - M.J.
Reply: Look for & trace moisture or water under the roof, explore for leaks during mold cleanup, don't look just for "black mold"
Our home page for roof leak detection, diagnosis, and repair (where to patch) is at LEAKY ROOF DIAGNOSIS & REPAIR. Excerpts are below.
If your roof is low slope or flat water travels and it can be tricky tracking down a leak - an inspector using infra red and moisture meters should be able to help sort out the question of whether there is an active leak and if so where it originates. As you report that the top floor occupant has found wet areas, it seems likely that other than concrete and structural members, other wet materials such as insulation will need to be removed - a step that will help trace the size and pattern of wet areas back to inspection points on the roof above.
It's common on large commercial buildings and apartments to simply add another layer of roofing over leaky flat or low-slope roofs. Sometimes the roofer will also put down a layer of insulating board first. As long as the roof can be mechanically secured soundly to the structure, that practice is acceptable in many communities.
But roofing over wet layers of old material can lead to future troubles including
If the roofer roofed over wet conditions they could take a long time to dry out, particularly if the roof was installed atop multiple layers of old material. You didn't say how long ago the new roof was installed nor whether or not there was a tear-off of old layers. Also, while we like modified bitumen as a roof covering material, the roof can "look good" but could have improperly made seams.
An experienced roofer or roof inspector will look closely at the modified bitumen seams and flashing details to be more confident that at least from above the roof doesn't show obvious leak points. See our detailed response to this question at LEAKY ROOF DIAGNOSIS & REPAIR. Also see MODIFIED BITUMEN ROOFING for details about the type of roofing installed on this building. .
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Search the InspectApedia website
HTML Comment Box is loading comments...
Technical Reviewers & References