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Roof algae stains: algae and occasionally fungal growth discolors roof shingles. This article explains methods for cleaning off and preventing future roof stains due to algae or "black fungal growth" or green algae on roof shingles, the effects of these conditions, and how to cure or prevent them. We provide a list of type of stains and colors that appear on roof shingles and on other roofing materials.

Also see Black or Green Algae for more photos of black algae stains on roofs. If your concern is specifically with moss on roof shingles, see MOSS & LICHENS on SHINGLES.

We cite and discuss roofing manufacturer shingle warranty exclusions or inclusions for algae and algae-related roof stains at ALGAE STAINS ON ASPHALT ROOF SHINGLES. Also see STAINS on ROOF SHINGLES. Or if your roof has rust staining from metal components, see Rust Stains on Shingles.

This website tells readers how to identify & explain the most-common asphalt roof shingle failures and how to obtain asphalt roofing shingle failure claims assistance. These defects occur on 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.

© 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.

How to clean off algae, mossy or lichens-covered roofs

Regardless of the cause of a roof stain, moss, or lichens, avoid aggressive roof cleaning methods (like scrubbing with a stiff brush or power washing) that might damage the roof surface. Before deciding to remove a roof stain, you should

First Step of shingle stain removal: Assure that the roof shingles are sound and thus not likely to be damaged by any cleaning procedure. Do not try to clean a roof like the one shown in this photograph. The shingles are worn out and fragile. It will be impossible to clean the roof without damaging it. A new roof is needed.

Second Step of Shingle Stain Removal: Test the roof stain as well as your stain cleaning method on a small area of the roof.

Identify what the roof problem or stain or material is: algae staining, debris staining (probably can be removed or cleaned gently) versus moss or lichens growth (probably will damage the roof during removal).

How to identify algae staining on roofs: there is a simple test of applying a light spray of a diluted mixture of trisodium phosphate [use a TSP substitute, not TSP which is an environmental contaminant] and chlorine (with water) in the proper proportion will determine weather or not this is algae quite readily. If it is asphalt pigment, it will not lighten.

While we have not confirmed its presence, some black stains on roofs and roof gutters might be due to black molds or sooty molds, for which the USDA has published How to Recognize & Control Sooty Molds. Black mold growth on leaves, on roof debris that has fallen from a tree overhead, or on an aluminum roof gutter, is not a predictor that any of the species discussed in the USDA article will appear as black "sooty mold" growth on a roof shingle.

Step Three of Shingle Stain or Debris Removal: clean the roof using the gentlest possible method

Watch out: don't try cleaning asphalt shingle roofs without checking with the manufacturer about their recommended methods. For example using power washers (not recommended), and some chemicals may damage the shingles and reduce the roof life. Other chemicals such as bleach may also cause staining on other building areas and can be unsafe if not handled properly.

Power washing or brushing to clean a roof? it is possible to remove moss or lichens from a roof surface by gentle cleaning using a soft brush or a garden hose. Power washing risks damaging shingles by blowing mineral granules off of the shingle surface (as does unnecessary foot traffic on a roof).

NRCA's James R. Kirby notes that if a roof's appearance is not acceptable and cleaning it is the preferred method of improvement, asphalt shingles should be washed with a mild solution of chlorine bleach or mild detergent, gently applied with a sponge or hand-held sprayer. The surface then must be rinsed thoroughly with water. Kirby continues to warn that cleaning off roof algae is only a temporary fix - it will reappear unless we take steps (discussed below) to prevent future algae growth.

Watch out again: As we discuss at Power Washing Roofs we do not recommend power-washing asbestos-cement nor any other roofing. In addition to damaging the roof surface, power-washing an asbestos-cement roof can create an environmental hazard.

Watch out again: Don't do what one of our readers suggested: she sprinkles a mix of Tide laundry detergent over her stained roof then pours bleach onto that surface. That's a dangerous maneuver for obvious reasons: slipping off the roof, ruining the shingles, staining building siding, killing plants and grass below.

However our direct inspection of roof shingle surfaces where moss or lichens have been removed using any method, even non-abrasives such as installing copper or zinc strips whose salts eventually kill those organisms, usually shows that there has been shingle granule loss and even exposure of the shingle substrate where the lichens or moss root action had affixed some of the mineral granule roof shingle covering. See MOSS & LICHENS on SHINGLES.

Furthermore, unlike the simple removal of black algae stains or debris stains from a roof, trying to mechanically remove moss or lichens is likely to also remove roof surface materials, damaging the roof and reducing its life. Where mineral granules are lost from an asphalt roof surface, such as due to lichens damage shown at ALGAE, FUNGUS, LICHENS, MOSS COMPARED, there is a real risk of increased deterioration rate or reduced roof life because of loss of the protection of the mineral surface coating. In some cases the result may be actual holes in the roof shingles and leaks that can damage the structure below.

Be very careful: power washing or even brushing or sweeping an asphalt shingle roof (or a wood shingle roof in old, worn, fragile condition) is itself a process that can damage the roof by breaking shingles or by loosening the protective mineral granules from the shingle surface.

That's why we prefer to use the most gentle method possible to remove moss, algae, lichens, or stains from roofs, and usually we leave moss and lichens alone except to take steps to reduce further growth of these organisms - discussed below at Remedies.

Some Roof Cleaning Chemicals may reduce or remove roof stains from algae or other causes. Be cautious: some chemicals intended "kill" the moss or lichens risk also damaging the shingles, staining building siding (such as using bleach) or contaminating the environment, and have the further disadvantage that they still leave the moss or lichens in place where it holds water on the roof surface. Some deck cleaning sprays such as StainhandleR roof and deck cleaner are also sold for use as cleaning solutions for stained roofs .

A Brief History of Algae-resistant AR-Shingles and What They Are Made-Of

Roofing manufacturers can provide shingles specifically made with an alternative type of mineral granule that resist algae growth. Earlier roofing manufacturers tried an algaecide coating to prevent algae growth. In the late 1980's manufacturers began using zinc granules but zinc was discontinued out of environmental concerns for using a heavy metal on roofs.

Zinc can also emit a "white rust" that builds up as a white stain or oxide. By 1996 manufacturers were using several coatings on asphalt shingles to reduce algae growth, including cuprous oxide coated granules mixed in with other granules on the shingle surface. The percentage of copper-coated granules (4% up to 10%) affects the resistance of the roof to algae.

Is algae the same as mold on roof shingles? Kirby's 1996 article confused algae and fungal growth on roofs as equivalent, which may be ok since the same chemicals that resist algae growth may also resist fungal growth and stains. We discuss removing sooty black molds on buildings below. By the way, most of the roof surface samples we have tested (pro-bono in our forensic laboratory) have been shown to be algae, not fungal and not extractive bleeding stains.

Shingle product names that include an "AR" suffix or "3M Algac Block" are products manufactured and warranted to be algae-resistant (OPINION-DF: "algae resistant" doesn't mean "algae proof", no?).

See Causes of Roof Stains and  Catalog of All Roof Stains for the causes and types of stains that occur on building roofs. Our complete list of types of black stains on building roofs is at Catalog of Black Roof Stains.

Removing Sooty Black Molds on Plastic or Painted Surfaces (not specifically roofs)

The USDA publication we cited above includes suggestions for removing sooty black molds (the author considers Cladosporium sp. and Aureobasidium sp. as sooty black molds though they may in fact be brown or black and may not easily wipe off as "sooty" molds). Quoting:

Sooty molds can be indirectly controlled by reducing populations of sucking insects that excrete honeydew. Outdoor furniture can be hosed down with water during periods of honeydew excretion, particularly during drought. The growth of sooty mold fungi is inhibited by preservatives used in treated wood in rustic outdoor furniture. Here is the recipe for a good cleaning solution for removing sooty molds from plastic or painted surfaces:

Be sure to wear rubber gloves when cleaning with this solution. [Note that trisodium phosphate is no longer used as a cleaning agent because it is an environmental contaminant. However substitute products may be available. Be careful not to add a cleaning agent to bleach that can cause production of toxic chlorine gas.

Remedies for & prevention of black algae staining on shingles

How to Prevent Algae or Fungal Growth on Roof Surfaces

Black stains on asphalt shingles caused by algae is avoided by some of the new roof shingle products which include chemicals to retard algal growth.

Cutting back overhanging tree branches for more sun can also help reduce this problem.

Zinc or copper strips tacked along the ridge will produce (in rain) metal salts which will kill algae, lichens, and moss as the zinc salts wash down the roof. New shingles offered by some manufacturers include algae resistant chemicals in their mineral granule coating.

Shingle Shield™ and StainhandleR and Z-stop™ are example of a zinc strip products intended for use in reducing roof growth of moss, lichens, algae.

Whatever cleaning is done on a roof surface, make sure the process does not cause more harm than good to the roof and to the environment around the building.

NRCA's James R. Kirby also noted that metal fixtures (galvanized steel or copper, and in our experience even aluminum) retard algae growth on roofs, and he, too recommends installing zinc or copper strips at the ridge to control algae growth, but warns they may not be effective over the entire roof slope because concentrations of zinc, copper, or other metal salts are more diluted further away from the strips. Installing multiple strips can thus be a more effective solution.

Trim back trees whose branches overshadow the roof surface. Keep the roof clean of organic debris like leaves or pine needles which may collect in valleys or at other roof locations.

Installing copper, zinc, or other metal strips along the ridge of an existing roof will slowly kill off algae, moss or lichens as rainwater washes over the metal and down the roof surface. Fungal stains may also be reduced; extractive bleeding stains may be unaffected unless simply being whitened by zinc salts.

This method is also suitable for both prevention of future or further moss or lichens growth on the roof and for gently treating an otherwise fragile old roof.

Our photo, left, shows an absence of moss or lichens on this wood shingle roof found in Key West, Florida - notice that the "clean" wooden shingles are all below the cupola and its flashing?

Chemically treated roof shingles are available from several asphalt roofing manufacturers who offer these products which are resistant to moss, lichens, or algae growth on roofs. Discuss this option with your roofer when it's time to replace the roof. See our discussion A Brief History of Algae-resistant AR-Shingles and What They Are Made-Of

For an extensive catalog of methods for preventing algae, moss, or lichens growth on roofs see How to Prevent Moss, Lichens & Algae Growth on Roofs

The differences among algae, lichens, and moss on roofs are described at ALGAE, FUNGUS, LICHENS, MOSS COMPARED where we also show what moss looks like under the microscope. And at ALGAE STAINS ON ASPHALT ROOF SHINGLES we show what roof shingle algae looks like under the microscope.

Also see TREES & SHRUBS, TRIM OFF BUILDING

List of All Types of Stains on Building Roofs, Surfaces, Walls

In the following guide we list types of stains by stain color & appearance, by building location or material, and by stain cause.We distinguish among the following stuff that may stain or be found growing building roofs, walls, or other surfaces, with extra focus on asphalt shingle roofs as well as other roofing materials such as wood shingles, wood shakes, roll roofing, and even slate or tile roofs. Some of these types of roof stains or discoloration are only cosmetic in nature, while others may indicate growths that are likely to reduce the roof covering life. A more detailed, illustrated version of the list below is given at STAIN DIAGNOSIS on BUILDING EXTERIORS.

• Algae-caused black or green stains on roof or other building surfaces - Some photos of black algae stains are at Black Algae Stains on Asphalt Shingles. For details on roof algae see ALGAE STAINS ON ASPHALT ROOF SHINGLES, and ALGAE STAIN TEST METHODS. Algae can produce black stains on asphalt roofing products. Also see  ALGAE, FUNGUS, LICHENS, MOSS COMPARED. And see STAIN DIAGNOSIS on STONE for examples of algae staining on other building surfaces.
• Black stains on asphalt roofing products such as asphalt shingles or roll roofing, caused by extractive bleeding (product defects) - see Bleed-Through and see Roofing material defect / environmentally-caused roof shingle stains.
• Black, brown, or gray stains on roofing products due to debris left on the roof surface, such as piles of leaves and organic waste from nearby trees. See Debris Staining and see Proximate cause roof shingle stains
• Black or other colored stains on roof surfaces may be caused by soot from chimneys, both wood-fired and oil-fired devices. Black or other colored stains may also appear on roof surfaces from nearby industrial activities. See Soot Staining.
• Black stains on building interiors: such as on carpets, drywall, or trim: see STAIN DIAGNOSIS on BUILDING INTERIORS and then STAIN DIAGNOSIS on BUILDING INTERIORS and also see STAINS on INDOOR SURFACES: PHOTO GUIDE
  
• Brown or red stains on roof surfaces are often caused by rust from wearing steel flashing or other on-roof metal products. See Rust Stains on Shingles.
• Catalog of Biological Substances that Alter Stone or Other Inorganic Materials lists the causes and types of damage that raise aesthetic and conservation issues on cultural artifacts, buildings, and art works.
• Chimney stains on roofs - see see SOOT STAINING - Black Soot Stains on Roof Shingles Around Chimneys and see Proximate cause roof shingle stains
• Debris stains on roof shingles - see Debris Staining - Black Debris Stains on Asphalt Shingle Roofs
• Extractive bleeding stains on asphalt roofs - see Bleed-Through and see Roofing material defect, and see Proximate cause roof shingle stains (types of roof stain by color, location, probable cause)
• Green roof stains on roof shingles, clay tiles, cement tiles, and asbestos cement roof shingles or newer fiber cement roof shingles are often caused by algae. For details see ALGAE STAINS ON ASPHALT ROOF SHINGLES. Moss on roofs is also often green and should be unmistakable in appearance. See ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES.
• Lichens growing on building surfaces - Lichens are not the same growths as moss or algae, and are difficult to remove without damaging the roof surface. See Lichens on Stone Surfaces, and also see Lichens on Roofs for details about how lichens can cause roof damage. See Methods for Cleaning Stone Surfaces and ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES for a guide to preventing lichen growth and stains. Also see ALGAE, FUNGUS, LICHENS, MOSS COMPARED for an explanation of the difference among these.
• Mold or fungus growing on roof surfaces or on other building surfaces - see ALGAE STAINS ON ASPHALT ROOF SHINGLES. See FIND MOLD in buildings, HOW TO for a guide to looking for mold contamination in or on buildings, and see WHAT MOLD LOOKS LIKE for a guide to just what mold looks like on building surfaces. Be sure also to see Stuff that is Mistaken for Mold to avoid becoming excited about harmless substances that people think are toxic mold. If you know your building has a mold problem, see ACTION GUIDE - WHAT TO DO ABOUT INDOOR MOLD.
• Moss on roofs and other building surfaces: see ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES, and Green Stains on Stone. Green or other colored mosses are a bit easier to remove than lichens on roofing surfaces, but both can carry away mineral granules and damage the roof surface. Moss tends to hold more water and moisture on the roof surface. So in our opinion moss is more likely to damage a roof surface than lichens or algae. Also see ALGAE, FUNGUS, LICHENS, MOSS COMPARED.
• Rust Stains on buildings - see Rust Staining - Red or Brown Rust Stains (on shingles)
• Soot or Creosote black or brown stains on roof surfaces near or below chimneys - see SOOT STAINING - Black Soot Stains on Roof Shingles Around Chimneys and see Proximate cause roof shingle stains
• Stains on stone or masonry surfaces - see STONE CLEANING METHODS for cause, cure, and prevention
• Tree-caused stains on roofs - see Proximate cause roof shingle stains
• White stains on roof surfaces may be from wash-down of pigments in paint on surfaces above the roof such as a gable end or dormer wall; white or less-black roof surfaces may also be found below copper or aluminum flashing whose salts run down the roof surface in wet weather, preventing algae or moss growth and leaving a white area on an otherwise stained roof surface. Our article at ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES includes a photograph of this condition on a wood shingle roof.

Questions & Answers regarding this article

Questions & answers about roof algae stains and black marks on asphalt roof shingles: causes, effects on roof life, cure & prevention.

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  ALGAE STAINS ON ASPHALT ROOF SHINGLES
  ALGAE STAIN TEST METHODS
  ALGAE, FUNGUS, LICHENS, MOSS on SHINGLES
  BLACK STAIN REMOVAL & PREVENTION

• Shingle Shield™ are zinc strips that are inserted under the shingle tabs of individual shingles to reduce moss, lichens, and algae growth on asphalt roofing - see shingleshield.com
• StainhandleR are zinc strips that are inserted under the shingle tabs of individual shingles to reduce moss, lichens, and algae growth on asphalt roofing- see stainhandler.com
• Zinc-Shield® - zincshield.com and Z-stop™ zinc roofing strips - z-stop.com, are roll-out zinc strips intended for installation near the ridge of a roof to reduce moss, lichens, and algae growth on roofs
• 04/09: thanks to William M. Norman, P.E., S.E., Keeler-Webb Associates, 486 Gradle Drive, Carmel, IN 46032 for opening discussion regarding the legitimacy of extractive bleeding as a term to apply to asphalt roofing material. Mr. Norman suggests that many (not all) black stains on asphalt roofing may be due to algal growth. We will report progress in this discussion as updates to this web article.
• How to Recognize & Control Sooty Molds, USDA publication on the recognition and control of black sooty molds, including on buildings. This publication is also available in printed form from the U.S. Government Printing Office, 1992 657-152 HT-69 1992. The original article was authored by Kenneth K.Kessler, Jr., Principal Plant Pathologist, U.S. Forest Service, in the Department of Agriculture of the United States. Copies are also available from North Central Distribution Center, Forest Products Laboratory, One Gifford Pinchot Dr., Madison WI 53705-2398.
• "Cleaning, preventing algae growth on asphalt shingles", James Kirby, Professional Roofing (NRCA), November 1996, p. 45
• NRCA - National Roofing Contractors Association - http://www.nrca.net/, 10255 W. Higgins Road, Suite 600, Rosemont, IL 60018-5607, Tel: (847) 299-9070 Fax: (847) 299-1183

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.

• 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)
• ...