When it comes to constructing a masonry wall, the installation of flashings is of paramount importance. These inconspicuous yet vital components play a crucial role in effectively managing water infiltration and preventing moisture-related damage to the structure. Flashings aren’t to be taken lightly as they need to be strategically placed in key areas such as foundations, bond beams, above and below openings, at shelf angles, and at copings. Additionally, incorporating weep holes and vents into the design further aids in reducing the moisture content within the wall, contributing to it’s overall health. However, it isn’t enough to simply install flashings haphazardly; careful consideration must be given to the selection of appropriate materials, meticulous detailing, and precise installation techniques. Taking these factors into account is vital in ensuring satisfactory performance and safeguarding the structural integrity of the masonry wall.
Where Is Through Wall Flashing Required?
Through-wall flashing is a crucial component of a well-designed building envelope and is required in various locations to effectively manage water intrusion. One important area where through-wall flashing is necessary is at grade. The point where the wall meets the ground is particularly vulnerable to water infiltration, making it imperative to apply flashing in this location. Without proper flashing, water can seep through the joint, leading to potential structural damage and moisture-related issues such as mold growth.
This includes areas such as parapets, roof-to-wall connections, and transitions between different wall materials.
Properly installed flashing plays a pivotal role in protecting the integrity of the building envelope and preventing moisture-related problems.
Roofs and Overhangs: Flashing Is Necessary in Areas Where Roofs and Overhangs Meet the Walls to Prevent Water From Getting Behind the Exterior Cladding.
- Flashing is necessary in areas where roofs and overhangs meet the walls to prevent water from getting behind the exterior cladding.
Flashing should be installed in various crucial areas of masonry construction such as foundations, bond beams, openings, shelf angles, and copings. These strategic placements help prevent moisture buildup and damage. Moreover, incorporating weep holes and vents aids in minimizing moisture content within masonry walls. By carefully selecting appropriate flashing materials, paying attention to detail, and executing proper installation techniques, optimal performance and longevity can be achieved.
What Is One Place Where Flashing Should Be Installed in Masonry Construction?
One place where flashing should be installed in masonry construction is at the foundation. This is crucial because it helps prevent water from seeping into the building through the gaps between the foundation and the masonry walls. By installing flashing at the foundation, it creates a barrier that directs water away from the building and protects the structure from potential water damage.
Another important area where flashing should be installed is at bond beams. Bond beams are horizontal elements within the masonry walls that help distribute load and reinforce the structure. Flashing installed at bond beams prevents water from entering through the gaps and joints in the walls, thus protecting the integrity of the structure and ensuring it’s longevity.
Above and below openings, such as windows and doors, is another critical area where flashing should be installed. Without proper flashing, water can easily penetrate through these openings and cause damage to the interior of the building.
Shelf angles, which are horizontal angles that support masonry veneer above openings, also require flashing installation. Flashes at shelf angles are essential for preventing water penetration and ensuring that the masonry veneer remains securely in place. Without flashing, water can seep into the gaps between the veneer and the shelf angle, leading to potential structural issues.
Flashing Installation at Roof-to-Wall Connections: Flashing Should Be Installed at the Junction Between the Roof and the Masonry Walls to Prevent Water Infiltration and Protect Against Potential Damage Caused by Leaks. This Is Especially Important in Areas With Heavy Rainfall or Snowfall.
When installing a roof that meets a masonry wall, it’s crucial to use flashing to create a barrier and prevent water from seeping in. By placing this protective layer at the roof-to-wall connection, you can ensure that no leaks occur and minimize potential damage. This becomes even more necessary in regions with high precipitation, such as heavy rain or snowfall.
Source: FLASHING STRATEGIES FOR CONCRETE MASONRY WALLS
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Flashing is a crucial component in construction that helps ensure water-tightness and prevent water damage. There are various types of flashing used in different areas of a building. For instance, wall flashing is commonly employed around windows to avoid water seepage, while sill flashing is hidden beneath windows or door thresholds to safeguard against water penetration. Additionally, channel flashing, designed as a U-shaped channel, is utilized to address the junction between a tile roof’s edge and a wall. These examples showcase the diverse applications of flashing in construction.
What Are Examples of Flashing in Construction?
Drip flashing: Installed at the lower edge of a roof slope, it directs water away from the buildings exterior walls. This prevents water from seeping into the structure and causing damage. It helps to protect the walls from water-related issues such as leaks, mold, and rot.
Valley flashing: Found in the valleys where two roof slopes intersect, valley flashing ensures that water flows smoothly off the roof. It’s commonly made of metal or other durable materials. Valley flashing plays a crucial role in preventing water accumulation, which could lead to leaks and structural damage. By directing water away from these vulnerable areas, it helps to maintain the integrity of the roof.
Step flashing: Utilized in roofing systems that have sidewalls or chimneys, step flashing prevents water from entering the junctions between the roof and these vertical surfaces. It consists of a series of small L-shaped metal pieces that are layered with the shingles. Step flashing provides a watertight seal and helps to channel water down and away from potential leak points.
Cap flashing: Positioned on top of parapet walls or along the edges of flat roofs, cap flashing serves as a protective barrier against water intrusion. It covers the vulnerable junctions between the roof and the vertical surfaces, ensuring that water doesn’t seep into the building. Cap flashing is typically made of metal, such as aluminum or copper, for it’s durability and resistance to water damage.
Counterflashing: Installed to protect the top edge of vertical surfaces, counterflashing is used in conjunction with base flashing. It’s typically made of metal, such as lead or copper, and is placed over the base flashing to provide an additional layer of protection. Counterflashing helps to prevent water from infiltrating the vulnerable joints and seams of the base flashing, ensuring the integrity of the construction.
Mortar, commonly applied on flashings to level the bottom course, doesn’t adhere strongly to plastic or metal flashings despite their bonding with the shelf angle.
Does Mortar Stick to Flashing?
When discussing the interaction between mortar and flashing, it’s important to consider the specific materials involved. In most cases, mortar is used to level the lowest course of flashings on foundations. However, it’s worth noting that mortar doesn’t typically bond well to plastic or metal flashing. This poses a challenge when trying to ensure a secure and durable connection between these materials.
Consequently, the mortar may not adhere properly, compromising the overall effectiveness of the flashing system.
To overcome this challenge, alternative techniques can be employed. One common approach is to mechanically fasten the flashings to the shelf angle, ensuring a secure connection without relying solely on mortar bonding. This method provides a more reliable and long-lasting solution for flashings on foundations.
This lack of bonding can compromise the effectiveness and durability of the flashing system. As a result, alternative techniques, such as mechanical fastening, should be considered to ensure a secure and reliable connection between flashings and the supporting structure.
Different Types of Flashings and Their Compatibility With Mortar
- Bonded Flashed with Mortar
- Chase Flashed with Mortar
- Stepped Flashed with Mortar
- Raglet Flashed with Mortar
- Saddle Flashed with Mortar
- Counter-Flashing
- Apron Flashed with Mortar
- Cap Flashed with Mortar
- Counterstep Flashed with Mortar
Conclusion
Striving for excellence in these aspects will enhance the overall quality and functionality of the masonry walls while providing satisfactory performance for years to come.