Issue #70 Flashings September 12, 2007

Contents: Issue #70 Flashings

  1. Basics: Improper, Drainage Planes, Flashing Q & A
  2. Types: Manufactured Pans, Flexible, End Dam, Sealant
  3. Design: Rainscreen, Problem Areas, Details, Durability
  4. Roof: Valleys, Chimney, Metal, Cedar, Ice Dams, Details
  5. Wall: Rain & Water, Decks, Recessed Windows, CAD
  6. Siding: Fibre Cement, Vinyl & Metal, Wood, Stucco, Brick
  7. More: BC Envelope Guide, Best Practices, Articles, Videos
  8. Ken’s Top Pick: If you have time to surf only one site

1. Basics: Improper, Drainage Planes, Flashing Q & A

Evidence Of Improper Flashing Techniques 
This cartoon from the US Integrated Building & Construction Solutions newsletter shows some building trades may lack a wee bit of understanding of proper techniques for flashing.

Understanding Drainage Planes & Flashing
Building paper, with diagrams, explains drainage planes, flashing, windows & doors, materials, and connections should be designed to shed or drain water to the exterior.

Q & A On Flashing & Housewrap
Here is an online Q & A section on flashing & housewrap from Journal Light Construction that answers many of the common questions on flashing challenges, techniques, and products.

2. Types: Manufactured Pans, Flexible, End Dam, Sealant

Manufactured Roof & Pan Flashings 
NAHB bulletin describes manufactured roof and pan flashing components, attributes, ease of installation, costs, plus listing of suppliers and links to more information and resources.

Pan Flashing Research & Field Evaluation  
NAHB Research Center summarizes their laboratory and field evaluations of pan flashing, sill protection, and water resistive barriers, plus lists suppliers of products and their contact info.

Flexible Flashing Types & Selection
Types of flexible flashings, tips on choosing the right material for the job, and listing of manufacturers contact information are all included in the Journal of Light Construction article.

Making End Dams For Header Flashing 
Canadian Jon Eakes outlines how to bend sheet metal into flashing end dams that do not need caulking, and references the National Building Code sections that cover head flashing.

Impact Of Sealant On Performance Of Metal Flashing 
Building Envelope Forum summarizes a study showing metal flashing, when using sealant, needs horizontal projections of 25 mm or more and drip-edge angle of between 30° and 60°.      

3. Design: Rainscreen, Problem Areas, Details, Durability

BC Details Of Rainscreen Wall & Window Flashing 
National Home Warranty online Reference Guide of Typical Rainscreen Wall & Window Details shows rainscreen wall and flashing that meet the new 2006 BC Building Code. (PDF) 

BC Details For Flashing Problem Areas
Travelers Guarantee has online exterior construction details that address most common problem areas on a single family home, including a number of flashing applications. (PDF)

Canadian Details For Flashing 
These online construction details from CMHC demonstrate proper flashing of roofs, walls, windows, doors, and skylights, plus a number of other building sections and components.

More Details For Flashing Applications 
Waterloo University displays construction details of envelope enclosure systems, curtainwalls, and chimney, deck, skylight, wall-roof, and window to precast wall flashing applications.

Designing For Durability With Roof & Wall Flashing 
Chapters 4 & 5 of the US PATH guide “Durability By Design” contain an overview and description of roof & wall flashing components, and procedures to control rain and water vapour.      

4. Roof: Valleys, Chimney, Metal, Cedar, Ice Dams, Details

Roof Valley Flashing 
Old House Web has descriptions and drawings of roof valley types, flashing techniques, materials, and tools, plus list of further sources of information and a listing of US suppliers.

Chimney Flashing 
Installing chimney base, step, and counter-flashings, and how to make a chimney cricket to divert water, are explained, with drawings, in this Journal of Light Construction field guide. 

Metal Roof Flashing 
These Metal Roofing Alliance online Ask The Expert forums have answers to many questions on products, procedures, and issues relating to the flashing of metal roof systems.

Cedar Shake & Shingle Roof Flashing 
Sections of the online roof manual by Cedar Shake & Shingle Bureau give descriptions and details for design, installation, and maintenance of cedar roofing systems and components.

Flashing To Prevent Ice Dams On Asphalt Roofing 
Asphalt Roofing Manufacturers Association bulletin describes a proper eves flashing technique that prevents damage from ice dams on low and normal slope asphalt roofing. (PDF)

JPG & CAD Details For Roof Flashing 
These online details, in JPG or CAD, from Engineered Wood Association, cover flashing & drainage of roof sheathing, underlayment, ridges, valleys, chimneys, skylights, and more.

Roof Flashing Technical Database 
National Roofing Contractors Association allows you to search their large library database of technical bulletins and reports on roofing, flashing, and other procedures and components. 

5. Wall: Rain & Water, Deck, Recessed Window, CAD

Rain Control In Walls
Building explains moisture control principles for building enclosures; driving rain moisture load; various control strategies including flashings; and good design practises.

Water Managed Wall Systems 
This article by Dr. Joe Lstiburek describes how to show water to the exit with well-detailed drainage plane and flashings for walls with wood, vinyl, brick, or stucco cladding. 2003 (PDF)

Details For Flashing, Housewraps & Windows
Building Science Corporation paper and drawings give you theory, design considerations, and details of effective water management of housewraps, flashings, and windows. (PDF)

Deck Ledgers & Flashing 
Taller deck ledgers and proper flashing can prevent debris collection and deck rot, according to this brief Remodeling Magazine article and detail drawing found on the eBuild site. 

Flashing Recessed Windows 
Journal Light Construction article, with drawings and pictures, shows you how to install flashing on recessed windows that are set anywhere from 2 to 12 inches into the framing.

JPG & CAD Details For Wall & Window Flashing 
Here are some construction details from the Engineered Wood Association for flashing of windows, doors, ledges & intersections, and house wrap, in both JPG and CAD formats.                    

6. Siding: Fibre Cement, Vinyl/Metal, Wood, Stucco, Brick

Siding That Keeps Walls Watertight 
Wood expert Paul Fisette of the University of Massachusetts describes job site issues and how to keep walls watertight with detailing of house wrap, flashing connections, and siding. 

Fibre Cement Siding 
These online instructions from James Hardie include flashing procedures for various types of fibre cement siding systems including lap & vertical siding, shingle, trim, and soffits.

Vinyl & Metal Siding 
The Vinyl Siding Institute installation manual, how-to video, fact sheet, and common installation questions all include flashing information that relates to both vinyl & metal siding.

Cedar Siding 
Western Red Cedar Lumber Association cedar siding guide explains preparation, considerations, materials, installation, flashing, rainscreen walls, and industry best practices. (PDF)

Stucco Walls 
Stucco Guru covers types of flashing, standards of definition and testing, locations, where and how sealants are applied, plus flashing of both new and replacement windows & doors.

According to this Journal Light Construction article the use of caulk and backer rod, along with proper flashing details, are important for keeping water out of EIFS at wall penetrations.

Brick Veneer
US Salt Lake Community College course material describers how a clear air space, through-wall flashings, and weepholes, will prevent damage from any water that gets behind the brick.

Details For Brick Masonry Construction 
Masonry Details has online, downloadable construction details that show the proper design and flashing of brick veneer for both wood stud walls and concrete masonry unit wall systems.

7. More: Envelope Guide, Best Practices, Articles, Videos

BC Building Envelope Guide For Houses 
BC Homeowner Protection Office sells this Building Envelope Guide For Houses that includes rainscreen and flashing details for various components of the building envelope. $55 

Canadian Best Practices Guide For Flashings 
CMHC Best Practices Guide For Flashings covers basics of flashings, where required, materials available, advantages and limitations, and quality assurance procedures. $89 CDN

Free & Paid Articles On Flashing & Housewrap
You can find free and paid online articles on flashings and housewrap products, applications, selection, procedures, and challenges & issues, at the Journal of Light Construction site.

Discussion Forums 
Journal of Light Construction has online industry discussion forums on exterior details that contain quite a number of discussions on flashing procedures, problems, and products.

Online Videos
These Louisiana University online training videos on water management in walls include a number of flashing techniques for different building envelope components and penetrations.                      

8. Ken’s Top Pick: Details >From National Home Warranty

National Home Warrenty Details
This National Home Warranty Reference Guide of Typical Rainscreen Wall & Window Details has construction drawings for rainscreen wall and flashing components that meet the new 2006 BC Building Code Part 9. (PDF) 


Dittie For Today: On Aging

A person is not old until regrets take the place of dreams. 
John Barrymore

 © Copyright 2007               Ken Farrish               All Rights Reserved
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