Recommendations for Good Brick Masonry Construction Practices
Brick masonry construction is a timeless and reliable method that requires careful attention to detail and adherence to best practices. Whether you’re a professional bricklayer or a homeowner considering a DIY project, following these recommendations will help ensure the durability, structural integrity, and aesthetic appeal of your brickwork.
From accuracy and tolerances to weatherproofing and movement accommodation, each aspect plays a crucial role in achieving a successful brick masonry construction.
1. Accuracy and Tolerances:
To lay a solid foundation for your brickwork, it is essential to establish accuracy requirements before commencing the construction. Aligning the brickwork with structural frames, designated openings, and adjacent elements is crucial. Exercise caution while installing shelf angles or other brickwork supports that are part of or attached to the structural frame. Consider laying two dry courses of brick for areas that demand high-quality work, reducing the need for excessive brick cuttings. This approach enhances the bond and facilitates the integration of proposed openings in higher sections of the wall.
2. Appearance:
The size variations in clay bricks pose a challenge to achieving perfect alignment and consistent bed joint widths. For enhanced aesthetic appeal, consider using accurately sized concrete bricks instead. Planning the positioning of perps (vertical joints) in advance can result in visually pleasing brickwork. For example, regularly plumbing every fifth perpend creates an attractive pattern that can be repeated throughout the entire height of the brickwork. Protect the brickwork from rain, frost, and adjacent activities that may impact its physical and aesthetic integrity. At the end of each day, remove boards and equipment to prevent rain splashes and consider acid cleaning if necessary, ensuring careful application and prompt rinsing with water.
3. Durability:
Select bricks based on their durability in relation to the expected degree of exposure. The mortar’s strength should align with that of the bricks to prevent cracks caused by differential movement. Properly curing the mortar and protecting it from frost action until it reaches the designated strength are essential steps. Incorporating insulating materials beneath water-tightness protection helps ensure durability and prevents damage caused by temperature fluctuations.
4. Structural Performance:
The structural performance of brick walls relies on various elements such as footings, lintels, shelf angles, wind posts, anchors or hangers, and cavity wall ties. Install these components according to the manufacturer’s recommendations and relevant code specifications. Avoid exceeding a brick-laying rate of 1.5 meters per day to maintain consistency and quality. Employ solid cross joints rather than using smaller dabs of mortar or tipping and tailing, which compromise the structural integrity. Ensure that the bearing capacity of shelf angles and similar objects is at least two-thirds of the brickwork width. Pay attention to the correct installation of cavity wall ties, as they play a vital role in connecting adjacent walls and optimizing their performance.
5. Weather-Tightness:
Maintaining weatherproofing in external cavity walls relies on the cavity acting as a barrier. Clean the cavity during brick masonry construction to prevent mortar protrusions and droppings that can compromise its effectiveness. Use either partial or fully filled cavities to achieve proper thermal insulation, but exercise caution and follow the manufacturer’s recommendations for constructing such walls. Fill all bed joints and cross joints adequately, as these joints significantly contribute to the weather-tightness of the masonry wall.
6. Thermal Performance:
To achieve optimal thermal performance, prevent any gaps in the insulating layers and ensure they remain dry before and after placement. Fully filled cavity walls are recommended when a high degree of thermal insulation is required. Follow the manufacturer’s instructions on proper installation techniques to achieve the desired thermal performance. Managing capillary water movement through joints in fully filled cavity walls presents a significant challenge that needs to be addressed with appropriate measures.
7. Movement Accommodation:
Anticipated movements, such as the expansion of clay bricks over time, should be accommodated by incorporating movement joints at appropriate intervals. Use compressible materials for these joints, and emphasize the importance of good workmanship. Discuss joint details with the mason before starting the construction to ensure proper planning and execution.
8. Holes and Chases:
Clear communication is crucial when dealing with holes and chases for services passing through brickwork. Produce detailed drawings indicating the locations of these services, enabling the brickwork subcontractor to plan and incorporate necessary variations in a timely manner.
9. Lead Flashings:
When installing lead flashings beneath the damp proof course, create a clean rebate in the brickwork or incorporate a wide bed joint with a timber lath to align with the front face of the brickwork. This preparation ensures the proper installation of lead flashings and helps maintain their effectiveness.
Brick masonry construction requires attention to detail and adherence to recommended practices across multiple aspects. From accuracy and appearance to durability, structural performance, weatherproofing, thermal performance, and movement accommodation, each recommendation contributes to a successful and long-lasting brickwork project.
By following these guidelines, you can ensure that your brick masonry construction not only stands the test of time but also showcases a visually appealing and structurally sound result.