How to make temporary repairs for leaky slate roofs
How to inspect, evaluate & repair slate roofs - the basics
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This article explains several holding actions to try to preserve slate roofs by making temporary repairs until proper slate roof repairs can be ordered. This series of detailed slate roof inspection and repair articles describes procedures for evaluating the condition of slate roofing. How to inspect, identify defects, and estimate remaining life of slate roofs are addressed. The article series also references slate repair procedures, repair slate sources, and slate quarries. Our page top photo shows a slate roof in Port Jervis, NY. This roof was coated throughout all of its surface in an attempt to slow roof wear and leaks.
We also provide slate sources and where to buy slate roofing materials and slate roofing tools and products.
Holding actions for older, damaged, or leaky slate roofs
If a client cannot afford to replace a slate roof a wiser course may
be to do nothing in the short run, other than to trap small leaks in an attic, or to tar leaky
areas.
Although these steps are not preferred, they are often better than
abandoning what may be a valuable roof of predominantly durable slates.
Tarring leak areas in a slate roof is a very unpleasant and ugly holding
action. However if a roof may be salvaged by deferring a proper repair
for a short time we'd probably tolerate this step.
Advising clients
that the only option is to complete a very expensive slate repair
immediately is likely to result in an asphalt roof-over which may,
in the long run, be a worse crime. This is clearly a matter of opinion.
What went wrong on the slate roof in our photo at left? Often the metal flashing has worn out and is leaking while the slates are still good on a roof - that's what happened at the valley of the roof dormer shown in the left side of our photo.
As a roof leak temporary repair or holding action the repairman tarred the roof valley over the dormer - which might have worked, but it looks as if during access to apply the tar the repairman walked on and broke and loosened slates in the area just below the valley.
You can also see tar running out from below some of the slates just under the valley, showing us the sequence of repairs. Five slates were replaced (notice the dark gray slates?). But the slate nails may also be failing on this roof - which could explain why there are loose, falling, and missing slates in the area of the "repair".
Where the slates are good but fasteners are failing, some roofers
may be willing to remove, salvage, and reinstall slates. Slates which
are less than 1/4" thick should be discarded. The increase in labor
costs for this procedure makes this "re-roofing" process expensive.
Some slate companies suggest
that this procedure might be selected as a continuing
repair/maintenance process so that over a decade of maintenance the
roof has been totally replaced.
It's likely that the total labor bill
for a drawn-out project will be larger than the costs of an all-at-once
repair. However this approach permits spreading out a large investment
over a longer and less painful period. -- Personal communication, Vermont Structural
Slate, December 1990
ASHI ethical guidelines require inspectors to have no financial connection
with work performed on buildings they inspect. But where further evaluation
and/or repair advice is needed it is perfectly proper, and in our
opinion advisable, to refer clients to experienced, qualified slate
roofers just as you would to an expert in another field for other
concerns.
For slate roofs, refer clients only to roofers who have experience
with slate materials. While we'd prefer to refer a client to three
reputable experts, if we could locate only one in our area, by our
opinion of what's most sensible, we'd refer to that one.
Contractors
who are not familiar with slate and confronted by a leak in a valley
or in an area of limited mechanical damage, may sell a complete re-roofing
job to an anxious owner.
Similarly, improper repairs or traffic on a roof with fragile fasteners
or slates, may cause much more new damage than was present before.
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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.)
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 Roofs , Steven Trapasso, presentation to NY Metro
ASHI, Inc. chapter seminar, November 1990.
The Old-House Journal , Special Roof Issue , April
1983, The Old-House Journal, PO Box 50214, Boulder, CO 80321-0214
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.
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.
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.
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
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).
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
"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
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