Wall Caps for Construction St. John's NL
St. John's, NL
St. John's, NL
Wall Caps for Construction
Source: MASONRY CONSTRUCTION MAGAZINE
Publication date: April 1, 2005
- What keeps wall caps from falling off the top of an exterior freestanding wall if a full flashing is used beneath the coping? Copings are typically attached to the top of masonry walls with dowels that extend through the flashing and engage the coping stones. Oversized holes are placed in the bottom of the coping stones to line up with these dowels. Mortar is then installed to fill the space between the holes and the dowel to prevent the stone from moving.
To prevent water penetration, the flashing must be sealed watertight around the dowels. In copper, stainless steel, and galvanized flashing, a cap is sometimes provided at the dowels, which is soldered to the sheet metal. Other times, the flashing and dowels are protected with a sealant. The sealant must be carefully installed and the surface must be properly primed.
The dowels used to attach the coping sometimes consist of eye bolts placed in the joints between coping stones. In this method of attachment, rods extend through the eye bolt into holes in the side of the coping stones. The flashing penetration must be sealed watertight.
For rowlock brick copings, corrugated galvanized steel anchors extend through the flashing. These anchors are built into the head joints of the rowlock brick course at regular intervals. As with the dowels, these anchors must be thoroughly sealed where they penetrate the flashing.