Chimney Shoulder & Side Leaks & Damage - construction & inspection details

Definition of chimney shoulder
Chimney shoulder construction & surface sealing approaches & alternatives
Approaches to sealing the chimney shoulder & sides against a building side wall
Questions & Answers about chimney shoulder construction, sealing approaches, inspection & defects
References

Click to Show or Hide Related Topics

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Chimney shoulder construction, flashing, and sealing: this article defines chimney shoulders and explains the construction and sealing difficulties peculiar to this portion of masonry chimneys. We describe different masonry chimney side & shoulder treatments used on brick chimneys, how people try to seal this surface against leaks and water damage, and how the chimney shoulder may be sealed against the building side wall. We include photographs of different chimney shoulder designs and flashing or sealing details along with comments about the leak or damage risks at each approach.

Common Sources of Building Leaks & Damage at Chimney Shoulders

Definition of chimney shoulder: a chimney shoulder refers to the sloped sides of a masonry chimney that are built where a chimney changes from wide width at its bottom to a more narrow width for its vertical reach to above the rooftop. Typically if you see a chimney that is much wider at its base (also see our page top photo) the chimney was built to include a fireplace or the entry of multiple flues.

Check the sloped shoulder of masonry chimneys that are shaped like the one in this photo. Where a fireplace has been built into a home, the chimney often widens to accommodate the fireplace.

The sloped chimney shoulder is difficult to flash successfully against the building siding. It becomes a common place for leaks.

Where the chimney shoulder is "stair stepped" such as we show here, there is also an extra risk of water or frost damage to the chimney, the flue, or the fireplace. A better installation includes a slate or concrete sloped cap on the chimney shoulder. When the chimney shoulder cap is installed it should also be sloped away from the house wall to reduce the chances of leaks into the wall itself.

We have often found rot and insect damage at building walls where a stair stepped chimney shoulder has leaked into the structure.

Examples of Chimney Shoulder Finishes & Treatments to Avoid Leaks & Damage

Smooth-Brick Closure of Sloped Chimney Shoulders

At below left the chimney shoulder was constructed with a steep-angled shoulder of smooth brick facing. This chimney did not suffer frost damage at its shoulders nor water entry at the building wall - but wait! What about that wide flashing extending out over the chimney shoulder. That's odd isn't it? You betcha. Now notice the iron band around the base of the chimney shoulder. This chimney shoulder was not leaking, but the entire chimney had been moving away from the house at a substantial distance - a costly chimney footing problem. Inspecting at the chimney shoulder for construction type and leaks led to discovery of an important and dangerous and costly issue. Details are at Chimney Movement, Ongoing vs Static.

Chimney shoulder leaks (C) Daniel Friedman

At above right is a second version of "smooth brick" treatment of a chimney shoulder. But this chimney shoulder is less steeply-sloped and happens to be on a shaded side of the home. The combination of lower slope on this shoulder and perhaps shade have conspired to promote moss growth in the mortar joints. Moss, in turn, holds water and moisture in the mortar joint, accelerating wear and in a freezing climate, frost damage. The use of J-channel at the wall to chimney surface joint (blue arrow) is itself not a reliable seal against water entry into the wall. Our photo is a bit askew so it's hard to say if this shoulder drains towards or away from the building wall.

Concrete or Mortar Seal at Stair-Stepped Chimney Shoulders

At below left, instead of capping the entire shoulder with concrete the mason tooled each stair-stepped chimney shoulder joint with a smaller quantity of sloped concrete. We were skeptical about the durability of this approach until we inspected this home located in Minneapolis Minnesota - an area exposed to severe winter conditions. The chimney on this older home was perfectly intact. The wall covering was stucco, however, a material difficult to seal against the chimney shoulder as our second photo (below right) illustrates. Incidentally, while the chimney shoulders were not a source of damage to the chimney at this home, the chimney had moved a bit away from the structure, a condition visible at upper sections of the chimney where the quantity of movement will generally be greater.

Caulking & Flashing Seals at Chimney Shoulders

Our chimney shoulder seal photo at below left illustrates a futile approach: sealing the chimney to the aluminum-sided building wall using caulk or other sealants. Differences in materials (brick, aluminum siding, wood framing) mean different rates of thermal expansion/contraction, and quite a bit of stress on the caulk joint, making this approach a bit unreliable. Watch out for leaks and insect damage in walls where you observe this detail. And notice that just below my pen the caulk-sealant is not really bonded to the (algae covered) brick surface. This is a leak point.

At above right a second chimney shoulder treatment method is illustrated on a New York home - the shoulder was sealed with a concrete cap and counter-flashing (but no flashing) was installed along the building wall.

Watch out: check closely for leaks into the building wall anyway - if that shoulder does not slope away from the building wall, water entry is difficult to prevent at this location.

Frequently Asked Questions (FAQs) about Chimney Shoulders

...

Ask a Question or Search InspectApedia

Questions & answers or comments about the construction, sealing, & inspection of chimney shoulders & sides for leaks & damage.

Ask a Question or Enter Search Terms in the InspectApedia search box just below.

Technical Reviewers & References

Related Topics, found near the top of this page suggest articles closely related to this one.

Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides:
- Commercial Building Inspection Courses - protocol ASTM Standard E 2018-08 for Property Condition Assessments
- Home Inspection Education Courses including home study & live classes at eleven colleges & universities.
- Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program.
  Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference Book, a reference & inspection report product for building owners & inspectors.
  Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
- The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones.
  Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
- The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors.
  Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
- The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
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. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com 11/06
Roger Hankey is principal of Hankey and Brown home inspectors, Eden Prairie, MN. Mr. Hankey is a past chairman of the ASHI Standards Committee. Mr. Hankey has served in other ASHI professional and leadership roles. Contact Roger Hankey at: 952 829-0044 - rhankey@hankeyandbrown.com. Mr. Hankey is a frequent contributor to InspectAPedia.com.
Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at ap@octoberhome.com

[5] Stephen Werner, General Manager, Chimney King LLC., P.O. Box 8, Gurnee, IL 60031, Tel: (847) 244-8860, Email: steve@chimneyking.com, Website: www.chimneyking.com . Mr. Werner is also a licensed home inspector serving clients in Wisconsin.

[6] Residential Masonry Fireplace and Chimney Handbook, James E. Amrhein, S.E., MIA, Masonry Institute of America, 2d. Ed., 1995, ISBN 0-940116-29-4. The MIA is in Los Angeles, CA 213-388-0472. This manual reflects the 1994 Uniform Building Code, Energy Conservation Requirements of California, and the U.S. Department of Housing and Urban Development - HUD. The complete UBC is available from the International Conference of Building Officials (ICBO), Whittier CA 310-699-0541.
[7] NFPA 211 - Standards for Chimneys & Fireplaces, NFPA 211: Standard for Chimneys, Fireplaces, Vents, and Solid Fuel-Burning Appliances, 2006 Edition (older editions and standards are found at the same bookstore)
[8] NFPA 211 - Standards for Chimneys & Fireplaces, NFPA 211: Standard for Chimneys, Fireplaces, Vents, and Solid Fuel-Burning Appliances, 2006 Edition (older editions and standards are found at the same bookstore), NFPA #211-3.1 1988 - Specific to chimneys, fireplaces, vents and solid fuel burning appliances.
- NFPA 211 - 3-1.10 - Relining guide for chimneys
- NFPA 211 - 3-2 - Construction of Masonry Chimneys
- NFPA 211 - 3-3 - Termination Height for chimneys
- NFPA 211 - 3-4 - Clearance from Combustible Material
- NFPA 54 - 7-1 - Venting of Equipment into chimneys
[9] NFPA # 54-7.1 1992 - Specific to venting of equipment with fan-assisted combustion systems.
[10] GAMA - Gas Appliance Manufacturers' Association has prepared venting tables for Category I draft hood equipped central furnaces as well as fan-assisted combustion system central furnaces.
[11] National Fuel Gas Code, an American National Standard, 4th ed. 1988 (newer edition is available) Secretariats, American Gas Association (AGA), 1515 Wilson Blvd., Arlington VA22209, and National Fire Protection Association (NFPA), Batterymarch Park, Quincy MA 02269. ANSI Z223.1-1988 - NFPA 54-1988. WARNING: be sure to check clearances and other safety guidelines in the latest edition of these standards.
[12] Fire Inspector Guidebook, A Correlation of Fire Safety Requirements Contained in the 1987 BOCA National Codes, (newer edition available), Building Officials and Code Administrators International, Inc. (BOCA), Country Club HIlls, IL 60478 312-799-2300 4th ed. Note: this document is reissued every four years. Be sure to obtain the latest edition.
[13] Uniform Mechanical Code - UMC 1991, Sec 913 (a.) Masonry Chimneys, refers to Chapters 23, 29, and 37 of the Building Code.
[14] New York 1984 Uniform Fire Prevention and Building Code, Article 10, Heating, Ventilating, and Air Conditioning Requirements
New York 1979 Uniform Fire Prevention & Building Code, The "requirement" for 8" of solid masonry OR for use of a flue liner was listed in the One and Two Family Dwelling Code for New York, in 1979, in Chapter 9, Chimneys and Fireplaces, New York 1979 Building and Fire Prevention Code:
[15] "Top Ten Chimney (and related) Problems Encountered by One Chimney Sweep," Hudson Valley ASHI education seminar, 3 January 2000, contributed by Bob Hansen, ASHI
[16] Chimney Inspection Checklist, Carson Dunlop, Associates, Toronto, Ontario
[17] "Rooftop View Turns to Darkness," Martine Costello, Josh Kovner, New Haven Register, 12 May 1992 p. 11: Catherine Murphy was sunning on a building roof when a chimney collapsed; she fell into and was trapped inside the chimney until rescued by emergency workers.
[18] "Chimneys and Vents," Mark J. Reinmiller, P.E., ASHI Technical Journal, Vol. 1 No. 2 July 1991 p. 34-38.
[19] "Chimney Inspection Procedures & Codes," Donald V. Cohen was to be published in the first volume of the 1994 ASHI Technical Journal by D. Friedman, then editor/publisher of that publication. The production of the ASHI Technical Journal and future editions was cancelled by ASHI President Patrick Porzio. Some of the content of Mr. Cohen's original submission has been included in this more complete chimney inspection article: InspectAPedia.com/chimneys/chimneys.htm. Copies of earlier editions of the ASHI Technical Journal are available from ASHI, the American Society of Home Inspectors.
[20] Natural Gas Weekly Update: http://tonto.eia.doe.gov/oog/info/ngw/ngupdate.asp Official Energy Statistics from the U.S. Government
[21] US Energy Administration: Electrical Energy Costs http://www.eia.doe.gov/fuelelectric.html
[22] Fireplace & Chimney Design, Repair Books - Fireplaces, Chimneys: design, repair
[23] Fireplace & Chimney Inspection Books - Inspecting and diagnosing chimney problems, fireplace problems, chimney & fireplace standards
[24] Ceramic Roofware, Hans Van Lemmen, Shire Library, 2008, ISBN-13: 978-0747805694 - Brick chimneys, chimney-pots and roof and ridge tiles have been a feature of the roofs of a wide range of buildings since the late Middle Ages. In the first instance this ceramic roofware was functional - to make the roof weatherproof and to provide an outlet for smoke - but it could also be very decorative. The practical and ornamental aspects of ceramic roofware can still be seen throughout Britain, particularly on buildings of the Victorian and Edwardian periods. Not only do these often have ornate chimneys and roof tiles but they may also feature ornamental sculptures or highly decorative gable ends. This book charts the history of ceramic roofware from the Middle Ages to the present day, highlighting both practical and decorative applications, and giving information about manufacturers and on the styles and techniques of production and decoration. Hans van Lemmen is an established author on the history of tiles and has lectured on the subject in Britain and elsewhere. He is founder member and presently publications editor of the British Tiles and Architectural Ceramics Society. Also available at the InspectAPedia Bookstore.
[25] Chimney Inspection Checklist, Carson Dunlop, Associates, Toronto, Ontario
[26] Chimney & Stack Inspection Guidelines, American Society of Civil Engineers, 2003 - These guidelines address the inspection of chimneys and stacks. Each guideline assists owners in determining what level of inspection is appropriate to a particular chimney and provides common criteria so that all parties involved have a clear understanding of the scope of the inspection and the end product required. Each chimney or stack is a unique structure, subject to both aggressive operating and natural environments, and degradation over time. Such degradation may be managed via a prudent inspection program followed by maintenance work on any equipment or structure determined to be in need of attention. Sample inspection report specifications, sample field inspection data forms, and an example of a developed plan of a concrete chimney are included in the guidelines. This book provides a valuable guidance tool for chimney and stack inspections and also offers a set of references for these particular inspections.
[27] Fireplaces, a Practical Design Guide, Jane Gitlin
[28] Fireplaces, Friend or Foe, Robert D. Mayo
[29] Principles of Home Inspection: Chimneys & Wood Heating (Principles of Home Inspection), Carson Dunlop
[30] U.S. vs. Canadian Unlined Masonry Chimney Flue Requirements & Case Study
[31] Brick Institute of America - Flashing Chimneys
Brick Institute of America - Proper Chimney Crowns
Brick Institute of America - Moisture Resistance of Brick
[32] American Gas Association - New Vent Sizing Tables
[33] Chimney Safety Institute of America - Chimney Fires: Causes, Effects, Evaluation
[34] National Chimney Sweep Guild - Yellow Pages of Suppliers
[35] "Building Codes that Regulate Decorative Chimney Shrouds", provided by Stephen Werner [5], [copy on file as Chimney_Decorative_Shroud_Regs.pdf] cites:
- International Mechanical Code IMC (2000), M74-98 806.6, ratified 9.98, model building code for the United States,
  806.6 Decorative Shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with section 304.1. Reason: Decorative shrouds have been the cause of roof and chase fires
- International Residential Code (IRC) (2000), R1002.2 ratified 9/99, 1000.2 Decorative Shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the manufacturers installation instructions. Reason: Decorative shrouds often allow for the creation of temperatures in excess of those permitted in UL 103 and UL 127. Decorative shrouds have been the cause of chase top fires ...
- International Fire Code (IFC) (2000), IFC 603.6.3, 603.6.3 Decorative Shrouds. Decorative shrouds installed at the termination of factory-built chimneys shall be removed, except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the manufacturers installation instructions. Reason: Decorative shrouds have been the cause of dozens of chase fires. As a non-listed part to a listed assembly, their use should not have been allowed in the first place.

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, 25th Ed., 2012, 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. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.

Building inspection education & report writing systems from Carson, Dunlop & Associates Ltd

Carson Dunlop, Associates, Toronto, have provided us with (and we recommend) Carson Dunlop Weldon & Associates' Technical Reference Guide to manufacturer's model and serial number information for heating and cooling equipment
Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
...


	InspectAPedia^®	InspectAPedia
	Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair	Ask a Question or Search InspectAPedia

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia