Masonry4

Masonry4

1. Clay Brick&Arch CMU

   • veneer for exterior wall cladding
   • Architectural CMU’s and Brick high strength durable against freezing & thawing.
   • mass of masonry veneer fire resistance & soundinsulating properties

2. Cavity Wall construction

   • concrete block was substituted as the loadbearing

3. Rainwatter infiltration control

   • exterior walls Barrier and Drainage.
   • exterior cladding is the first defense against water/moisture
   • drainage wall employing the rain-screen more w. resistant
   • provision is made to drain the air space using weep holes.
   • exterior cladding, air space, flashing, water-resistant backup and weep holes filtration free

4. Anchored Masonry Cladding

   • bldgs of all heights & complexity.
   • singlewythe 90mm masonry wall connected to the backup wall with steel anchors which transfer lateral load to the backup wall
   • Backup wall load-bearing or non-load bearing, and consists of reinforced concrete,concrete masonry, wood or steel stud.

5. Conventional Connectors

   • dovetail slot anchors/ties are suitable for low rise good cwc
     • unsuitable for high-rise construction, or where structural backing is other than masonry.
   • Dovetails to tie masonry veneer to concrete backing, & over concrete beams/ columns in masonry infill panels

6. NON CONVENTIONAL

   • adjustable ties engineered to suit modern masonry construction
   • 2 or more components
   • vertical adjustment to facilitate any non-alignment of mortar beds
   • between the exterior masonry wythe and the masonry backing.
   • Anchors must have sufficient rigidity & allow little movement in the plane perpendicular to wall.
   • upward-downward, & side-to-side movement because the veneer and backup wall expands/ contracts at different rates

7. Shelf Angles

   • mid and high-rise buildings, the veneer is generally supported at every second floor using hot-dip galvanized steel shelf angles.
   • anchored (welded or bolted) to the spandrel beams.
   • top of the veneer and the bottom of the shelf angle accounts for vertical expansion & beam deflection.
   • gap treated backer rod and sealant.
   • masonry veneer may project,not exceed 1/3rd of the veneer thickness
   • not be continuous. A maximum length of 6 000 and a gap of 9mm between adjacent lengths provides for thermal movement.

8. Loose Shelf Angles

   • Hot dipped galvanized steel lintels are placed loose on the masonry veneer at openings
   • not anchored to the building’s structural frame
   • No mortar is placed between the lintel bearing & the masonry veneer
     • Lintel moves horizontally

9. Air Space

   • max. distance between the masonry veneer and the backup wall is limited by code
   • Larger gaps require engineered anchors to withstand the compressive forces imposed on them by the lateral load
   • larger (50mm) reduces bridging risk, current insulation requirements have reduced the air space to 25 mm

10. Flashing

    • At the foundation level (left); Over a shelf angle; Over a lintel angle (left); and Under a window sill.
    • Joints must be sealed
    • project beyond veneer face to ensure water will drain outside
    • terminations, flashing must be turned up to form a dam to prevent water from entering the air space

11. Weep vents

    • above the flashing
    • sized to fit into a standard open-head masonry joint , in polymer mesh or plastic.
    • spaced every 600mm.

12. Mortar-capturing Devices

    • Excessive mortar droppings in the air space bridge the space and clog
    • polymeric mesh are placed above the flashing to trap droppings and suspend them allowing water to percolate to the weep

13. Movement Joints

    • constant state of movement
    • connectors by design restrain movement
    • caused by temperature, moisture and/or elastic deformation, shrinkage and creep.
    • Restraint introduces stresses, & if the capacity of the masonry is exceeded, then cracking occurs.
    • horizontal and vertical movement
    • near corners; changes in wall height; at offsets; differential settlements are anticipated; astructural steel or other items have penetrated masonry

14. Running and stack bonds

    • bond in a rainscreen veneer is for aesthetic reasons only
    • Masonry veneer acts as cladding

15. Veneer Arches

    • nonstructural, require a curved steel lintel to handle
    • building will have a CMU backup wall as opposed to wood or steel stud to allow tie placement anywhere
    • alternative is to use a block backup wall only at the locations backing