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ROOFING INSPECTION & REPAIR
AMERICAN CEMWOOD ROOFING
BEST ROOFING PRACTICES
BUILT UP ROOFS
CATHEDRAL CEILING VENTILATION
CERTIFICATIONS for ROOFING CONTRACTORS
CHIMNEY FLASHING Mistakes & Leaks
COLD WEATHER ROOF TROUBLE
DECKS, ROOFTOP CONSTRUCTION
EPDM, RUBBER, PVC ROOFING
EXTRACTIVE BLEEDING on SHINGLES
FIRE RETARDANT PLYWOOD
FLASHING on BUILDINGS
FLAT ROOF MOISTURE & CONDENSATION
Green House or Solarium Roof Leaks
HEAT TAPES & CABLES on Roofs for Ice Dams
ROOF ICE DAM LEAKS
MASONITE WOODRUF FIBERBOARD ROOFING
NOISE CONTROL for ROOFS
PLASTIC ROOFING TYPES
PVC, EPDM, RUBBER ROOFING
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
ROOFING FELT UNDERLAYMENT REQUIREMENTS
ROOFING MATERIALS, Age, Types
ROOFING TILE SHAPES & PROFILES
ROOFING UNDERLAYMENT BEST PRACTICES
SADDLE CONSTRUCTION at CHIMNEYS
SNOW GUARDS & SNOW BRAKES
STANDARDS for ROOFING
STRESS SKIN INSULATED PANELS
TEST LABS - ROOF SHINGLE
TREES & SHRUBS, TRIM OFF BUILDING
TRUSSES, Floor & Roof
UNDERLAYMENT REQUIREMENTS on ROOFS
VENTILATION in BUILDINGS
WALK-ON ROOF SURFACES
WARRANTIES for ROOF SHINGLES
WORKMANSHIP & ROOF DAMAGE
Here we describe roof safety and roof damage issues when inspecting, repairing, or otherwise walking on other roof materials such as asphalt, slate, wood roofs. This article tells readers how to identify fragile or unsafe roof surfaces, when to stay off of them, how to repair them. By listing common causes of asphalt roof shingle failures and how to recognize them, building owners and roofing contractors may also be able to reduce the occurrence of asphalt roof shingle storage, handling, and installation errors that affect roof life
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Foot Traffic Damage to Roofs: Walking on some roofs causes damage as the photograph at the top of this page shows. That roof damage occurred when an inspector stepped on the fragile corner of an asphalt roof shingle. This pattern of breakage traced his footprints right up the roof to the chimney and back down the other side. These are the very "footprints of damage" which we have reported in some other articles on fragile, old, worn roof shingles.
This "failed" roof was not leaking until the fellow who was asked to inspect it walked across this fragile surface. From a ladder at the roof edge one could clearly see the virtual footprints of broken shingle edges where the "inspector" had walked. In this case the "inspector" was a roofing contractor who came back down to the ground and told the home owner that she needed a new roof right away.
She was upset because her ASHI-certified home inspector had said that the thought she could use the roof for another two to five years. Our opinion was that she did need a new roof very soon but that had not been the case until "bigfoot" had stomped all over it.Worn out fragile roofs: The roof in the photograph shown here is one which is worn out, probably already leaking at least into the layers of roofing material, and it is so fragile that it should not be walked-on. I would stay off of worn, brittle, or cupped-shingle roofs, particularly in cold weather (shingles are more likely to break).
If we absolutely have to walk on such a roof, we would tiptoe carefully, avoiding stepping on the raised or cupped shingle sections, or if doing repairs, we would prop a ladder up off of the roof surface and work from that scaffold as is sometimes done with slate or other fragile roof surface repairs.
Guidelines for Direct Walking-On Inspection of Various Roof Surfaces & Roof Conditions
Some home inspectors reduce their workload and speed the the job by asserting that they do not walk on any roof surface under any condition, citing reasons of safety or fear of damaging the roof surface. But expert inspectors generally agree that there are many roof areas, conditions, and important roof defects, even total roof failure (such as thermal splitting), that are simply not visible except direct access to the roof edge (by ladder or other means) or by walking on the roof.
Watch out: Do not try to walk on any roof which is: too high, steep, wet, slippery, fragile, or covered with loose mineral granules, or other loose roof surface debris - such roofs are not suited for safe access. Do not walk on any roof which is installed over an incomplete, damaged, or rotted surface, as you might, like my helper on one roofing job, fall right through the roof surface!
Advice About Walking on & Inspecting Asphalt Shingle Roofs
We do not walk directly on any asphalt shingle roof that has one or more of these hazards:
Loose mineral granules on an asphalt shingle or roll roofing roof surface, are dangerous and can cause the inspector to slip and fall off of the roof, regardless of the cause of loose material: whether because the roof is brand new (initial granule loss due to wear during installation) or old (mineral granules are loose because of age and loss of adhesion, weather exposure, or foot traffic).
Advice About Inspecting & Walking on Cement Asbestos or Fiber Cement Roofs
Cement asbestos roof shingles: these shingles are as fragile as slate; it's best to stay off of this surface. Though we've walked
carefully on a few such roofs it's easy to damage them. See our inspection advice at ASBESTOS CEMENT ROOFING and our advice about tile and slate roof inspections found in this document (below).
Advice for Walking on & Inspecting Clay Tile Roofs
To prevent breakage, walk on tiles with extreme caution. Profile tile and lightweight tile are the most vulnerable, and concrete tiles are more fragile when they are freshly manufactured or “green.” If possible, place antennas and other roof-mounted equipment where it is easy to access without crossing many tiles.
When it is necessary to walk on tiles, step only on the head-lap (lower 3 inches) of each tile. With Mission- or S-tiles, it is best to step across two tiles at once to distribute the weight. When significant rooftop work is required, place plywood over the tile to distribute the load.
Watch out: our own experience is that it is absolutely impossible to walk on many clay tile roofs without damaging them, particularly soft clay such as the roof type used in Latin America (our photo at left).
For these roofs contractors have to remove sufficient clay tiles to provide a walking area. The removed tiles are replaced as the worker is leaving the work area of the roof.
Below we show two photos of a low slope (leaky) flat shingle-style clay tile roof on a New York Home. The ease of access meant that this roof was walked-on by someone (not us) who broke many clay tiles. You'll also notice the flattened metal tabs that were intended to hold replacement tiles in place. The tabs appear to have been bent flat by snow sliding down the roof, thus permitting clay tiles to begin to move as well (see the loose tile in the center of our photo at below left).
On some other fragile but not totally fragile roofs such as slate roofs, cement tile, cement-asbestos, fiber cement, and hard-fired ceramic clay tile roofs, contractors suspend a ladder over the roof surface, hanging it from the ridge, and cushioning it off of the roof surface using foam or insulation padding, or contractors work from scaffolding. - Ed.
Advice for Inspecting Other Fragile or Unsafe Roof Surfaces
Advice for Walking on or Inspecting Metal Roofs
Metal roof surfaces: can be walked-on provided
(1) the roof is not too steep and
(2) the metal roofing was installed
over closely-spaced nailers or sheathing. Beware that some metal roofs may be installed directly over rafters and widely
spaced horizontal nailers, and may be fragile or subject to denting.
Advice About Walking on & Inspecting Slate Roofs
Slate roofs are fragile and are likely to be damaged by foot traffic;
it's best to stay off of slate roof surfaces during a building inspection. See
SLATE ROOF INSPECTION PROCEDURE for details.
Inspectors should be cautious in evaluating any roof condition to avoid failing the roof material itself when leaks are confined to flashing areas.
Watch out: our own experience is that it is absolutely impossible to walk directly on slate roofs without damaging them, particularly if the slates are worn, loose, damaged. And walking on such surfaces is unsafe.
On some other fragile but not totally fragile roofs such as slate roofs, cement tile, cement-asbestos, fiber cement, and hard-fired ceramic clay tile roofs, contractors suspend a ladder over the roof surface, hanging it from the ridge, and cushioning it off of the roof surface using foam or insulation padding, or contractors work from scaffolding.
Our photo (above left) shows a slate roof being replaced in Duluth, MN. Notice the pairs of ladders that are used to install new slates without walking on this roof surface. The ladders address both a steep slope falling hazard and the probable damage to the slates from foot traffic.
Advice for Walking on & Inspecting Wood shingle roofs:
We've walked on new, good-condition wood shingle roofs but they are easily damaged
by foot traffic which can cause splits in the shingles. In addition
wood shingles are often slippery and dangerous to walk on and absolutely slippery when wet.
Advice for Walking on or Inspecting Wet, Icy, Steep, Snow-Covered Roofs
Wet, icy, or snow covered roofs are unsafe to walk on in most circumstances, possibly excepting expert inspection of flat roofs with safe parapets or railings installed.
Also see Building Safety Hazards Guide, and see our list of inspector safety articles at Home Inspection Education & Services - Safety Articles. Readers are also invited contribute roof failure information to the web author for research purposes. web author for research purposes.
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