Masonry Magazine June 1997 Page. 24
To install glazed brick, begin by laying the field brick with the coring/cells laid vertically. This allows gravity to work for you draining the water down through the wall. The walls should be designed with a 2-inch cavity between the interior and exterior wythes. The design should include proper flashing with weep holes and vents (Ref. 4). Flashing is necessary at the base course, sills, coping, at shelf angles and below all wall openings. When installing the flashing it should be extended beyond the edge of the wall. Weep holes, open head joints or vents should be placed at the foundation support spaced at 24" on center. Above lintels and spandrel beam supports in curtain and panel walls place weep holes 32" apart. Place vents in the top of the wall and at shelf angles 36" on center. This allows for air circulation within the cavity to promote moisture evaporation. Be sure to keep the cavity clean and the weep holes/vents open and mortar-free.
For glazed brick walls that are enclosing areas where the inner wythe will be heated, a vapor barrier should be placed on the inner wythe or warm side of the cavity. Coating this inner wall with a water emulsion type of asphalt paint will reduce condensation within the cavity.
Expansion Joints, Wall Ties and Anchoring
Glazed brick made of fireclay generally undergo much less expansion that other types of masonry units. Brick do not reverse this growth. A 3/4" expansion joint should be provided for every 100' of wall (Ref 4). At corners place an expansion joint on each side of the corner from 4' to 10' back from the corner. Soft joints should be placed under coping, sills and shelf angles.
Wall ties connecting two wythes of masonry should be placed at least every 16" vertically and every 32" horizontally. Ladder type reinforcement can be used where more strength is required. Vertical reinforcement can also be accommodated in some loadbearing glazed brick in the larger nominal 6" and 8" bed depths. Flexible anchors should be used at beams and columns to allow for movement.
Aquarium of the Americas, New Orleans, Louisiana. Constructed in 1994 with 100,000+ units. Addition in 1995 of 63,000 units. This project is located along the Mississippi River where there is dirty barge traffic flowing. The architect wanted to design a building that gave a church-like quiet but also the feeling of crisp, cool, clean, flowing water. He decided on a 3M (6"x6") structural glazed facing tile unit in three custom shades of white. As you can see from the photographs two of these whites are glossy and one has a matte finish in a very impressive pattern. The units were each color coded at the plant in an effort to work with the mason contractor in keeping his productivity rate up.
Mortar
Most glazed brick jobs will use either Type N or Type S mortar, as specified. Mortar selection and preparation should be based on ASTM C-270 (Ref. 5), according to the strength requirements necessary. Glazed brick generally have a low rate of absorption and need less water when mixing the mortar giving it a stiffer consistency for ease of laying and less floating of the units in the wall. Never wet the brick. Lay the brick with full head and bed joints. Do not use any type of sealer on the mortar joints when installing exterior glazed brick. You must allow the joints to "breathe".
Cutting/Drilling
Glazed brick are usually more dense and therefore harder and more brittle than concrete block and some brick. For this reason it is best to use a continuous-feed wet-cut masonry saw. A diamond grit continuous-rim blade is suggested for the best results. Using a dry-cut saw or other abrasive blade may result in excessive chippage or damage to the material or possible personal injury.
When drilling it is best to use a low-speed water-fed drill with a diamond segmented drill bit. Always keep water on the area while drilling and never allow the drill to become overheated.
Caution should be used when handling glazed brick especially if the glazed surface has been broken resulting in a razor-sharp edge. Proper protective clothing, gloves and eyewear should be worn as directed in the material safety data sheet.
Touchup paint is normally available from the manufacturer as a service to the masons. It can be used on minor chips that do not require unit replacement. Touchup paint is applied with a cotton swab to the chipped area then wiped off. Be sure to give your