Activity

  • burnhamlillelund94 posted an update 2 months ago

    Read about the most recent changes and happenings at

    Log into your account or register as a new author. Start submitting your articles right now!

    Search our database for articles.

    Subscribe to receive articles emailed straight to your email account. You may choose multiple categories.

    read this submitted by our authors.

    View our most top rated articles rated by our visitors.

    Please note that this is NOT the ARTICLE manager

    Add a new EZINE, or manage your EZINE submission.

    Add fresh, free web content to your site such as newest articles, web tools, and quotes with a single piece of code!

    Brick Walls Moisture Intrusion Defects by Alan Trauger

    Brick Walls Moisture Intrusion Defects by ALAN TRAUGER

    Article Posted: 06/08/2010

    Article Views: 3102

    Water leakage through brick clad walls is one of the most difficult masonry problems to correct. These leaks can cause severe damage to underlying wall elements and to interior finishes as well as disrupting building occupants. Excessive water entry into the wall usually results from poor brick workmanship. Water penetration into interior spaces may result from errors in design and / or construction of the wall drainage system. In most cases, leaks can easily be avoided if the designer properly details the flashing and weep system and carefully monitors construction for quality workmanship and conformance with design.

    The two most common types of exterior brick clad walls in existence today are the barrier and the cavity wall walls. Barrier walls block water from passing completely through the wall, thus preventing leakage into the building interior. Cavity walls provide a continuous void within the wall that serves as a channel to guide water out of the walls before it reaches the interior. Both barrier and cavity walls require good quality brick workmanship and a proper flashing and weep system to function properly.

    Durability Because exterior masonry will be exposed to moisture and the elements, durability is a primary concern. Durability of the brickwork is affected not only by the durability of individual materials, but also the compatibility of materials, how the assembly is designed, how materials are installed and the conditions to which the masonry is exposed. The best design, detailing, and materials will not compensate for poor construction practices and workmanship. Proper construction practices, including preparation of materials and workmanship, are essential to achieve a water resistant brick masonry wall.

    Masonry walls constructed of brickwork have performed well for centuries and are a testament to the performance and durability of brick. Design and detail that maximizes the water penetration resistance of brickwork is needed to achieve this level of service.

    Selection of the wall type should be based on the project’s location, environmental conditions and building use. Water penetration resistance of brickwork is enhanced by including appropriate details that reduce water penetrations at key points in the brickwork. Before brick veneer became popular, masonry walls usually functioned as both the structural system and as the exterior skin of the building. As a result, these masonry walls were quite massive, ranging in thickness from 12 inches up to 6 feet of solid brick. These masonry walls, both because of their thickness and their being in constant compression due to the structural loads, worked quite well in keeping water out of the interior of the building. Additionally, many older masonry walls were built with the cornices and other ornamentation which helped to protect the faces of the buildings from excessive water rundown and subsequent water penetration to the interior.

    Today, barrier wall systems are typically constructed with multi-wythe walls with mortar or grout filled collar joints, reinforced brick masonry walls and adhered veneer walls. The basic concept is that when a wind driven rain penetrates the exterior wythe of masonry it migrates inward toward a filled collar joint that acts as a barrier to prevent further inward movement. The water then migrates back out of the wall system. Flashing is then integrated into the barrier walls to aid in controlling water that penetrates the exterior wythe. It is recommended that the face of the inner masonry wythe should be parged (water-proofed) and the back of brick in the exterior wythe buttered, filled in, in order to fill the collar joint.

    Drainage Wall Systems

    This includes cavity walls (metal tied and masonry bonded hollow walls in historical applications, and anchored veneer walls. The basic concept behind the drainage wall assumes a heavy, wind driven rain will penetrate the exterior wythe of brickwork. When it does, the drainage is designed to allow the water to flow inward to the air space or cavity between the wythes. The water then flows down the back face of the outer brick wythe, where it is collected on the flashing and redirected out of the wall system through the weeps. Properly designed, detailed, and constructed this type of wall system are excellent with respect to water penetration resistance. Detailing Brick Veneer

    Through-Wall Flashing is a membrane installed in a masonry wall system that collects water that has penetrated the exterior wythe and facilities its drainage back to the exterior. This flashing is essential in a drainage wall system and is required as a second line of defense in a barrier wall system. Proper design requires flashing at wall bases, window sills, heads of openings, shelf angles, projections, recesses, bay windows, chimneys, tops of walls, and at roofs.

    Weeps are required to properly drain any water collected on the flashing. Weeps are required immediately above the flashing at all locations. Weep openings are permitted by most building codes to a have a minimum diameter of 3/16”. Weep spacing is permitted by most building codes at up to 33 inches.

    Drainage

    The air space must be kept clear of mortar droppings to allow proper drainage. Drainage materials may be specified that prevent mortar from entering the air space or catch mortar droppings at the wall base. While it is not mandatory to include drainage materials, they may help keep the air space open for drainage. Good workmanship is an essential to keep the air space clean.

    Critical Locations

    Wall Base. Moisture that enters a wall gradually travels downward. Continuous flashing must be placed above grade of walls to divert this water to the exterior. In addition, base flashing prevents water from rising up into the wall system due to capillary action and helps prevent efflorescence. The elevation of flashing and weeps should be above planting beds, ground covering, sidewalks, etc. that are placed immediately adjacent to the wall. No flashing should be place below grade.

    Window Sills should be sloped to drain; 15 degrees is recommended. Through wall flashing must be placed under all sills and turned up at the ends to form dams.

    Steel Lintels. Through wall flashing should be installed over all openings including door and window heads. Weeps are recommended above all lintels which require flashing.

    Shelf Angles, Projections, Recesses and Caps, Tops of Wall and Parapets are other locations that require special treatment inclusive of waterproofing, flashing, drainage, caps, copings, and etc.

    Alan Trauger is a Real Estate and Building Consultant for residential and commercial properties. Mr. Trauger has attained over 35 years of diversified experience and knowledge in construction, finance, and real estate. He has been involved in various facets of asset management, acquisitions, real estate work outs, property management, construction, inspection analysis, development, sales, leasing, and Ad Valorem tax appeal for over 25,000 single family and multi-family units and over 2.5 million square feet of commercial buildings. A Court Appointed Receiver and Expert Witness. An experienced and knowledgeable problem solver, understanding processes, and issues related construction and real estate.

    Mr. Trauger’s wide spectrum of experiences, education, research, teaching, and publication of previous articles, commercial real estate market sales comparables, and textbooks enables him to assist property owners through the property assessment and tax appeal process.

    To learn more about how your real estate tax assessment is prepared and how to appeal your property taxes. Property Tax Reduction Manual

    Do you Agree or Disagree? Have a Comment? POST IT!

    Reader Opinions

    Make this comment

    Name:

    Email:

    Your email will NOT be posted. This is for administrative purposes only.

    Comments:

People Who Like Thisx

Loading...