Grout for reinforced masonry walls is usually specified to meet the requirements of ASTM C 476. Only fine aggregate (sand) is allowed in fine grout, while coarse grout can contain up to 35% coarse aggregate. The aggregate used in masonry grout is specified according to ASTM C 404, and all coarse aggregate for masonry grout must be able to pass through a screen with 1⁄ 2- inch-square openings, making it equivalent to a 3 ⁄ 8-inch aggregate.
Corrugated wall ties are only allowed, by code, to be used in veneer work on wooden studs. If brick is veneered over concrete block, or concrete backing- only wire anchors, adjustable anchors or joint reinforcement is allowed by code. That is the LAW!
When we have a brick veneer over a wood frame and the designer chooses to have a wall begin with a brick veneer at the base and then transit on to another material such as wood or vinyl siding, the uppermost course of brick should be detailed with the same consideration as a window sill.
In today’s building climate, 4-6 story multifamily and office structures are common to the suburban Chicagoland landscape. Many builders wisely choose fire-resistance rated masonry walls and concrete plank floors for these structures. When it comes to roof construction, however, concrete is often overlooked in favor of a more aesthetically pleasing pitched roof system.
To secure masonry veneer to a backup system or to connect two or more masonry wythes, wall ties—made of wire or sheet metal—are necessary. Horizontal joint reinforcement also can be used to tie wythes together. But how do you choose from the thousands of available shapes, sizes, gauges, and steel types of masonry wall ties?
Building Construction and Design – Viewpoint: Density-Related Properties Of Concrete Masonry. This Viewpoint addresses the effects that density has on the physical, aesthetic, engineering and economic characteristics of concrete masonry walls.
Many factors influence the method a contractorchooses to place grout in a reinforced masonry wall. The volume of grout involved, the number and location of door and window openings, and the type and size of masonry units all must be considered. But many contractors agree that grouting a wall a full story at a time is the most efficient method, and say they prefer it whenever conditions make it feasible. Architects and engineers recommend it as a way to eliminate cold joints in the grout that can weaken the wall.
The introduction of a Concrete Masonry banding in a clay brick veneer wall is a popular design element, as it is for using concrete masonry veneers for entire walls. Using 4”split face units, ground faced units, glazed block, half high concrete masonry units or simulated stone units made of concrete are all commonly used as a banding course or courses within a brick wall.
Getting mortar into a thin joint between already-placed units can be a difficult, messy and expensive operation. Some innovative companies, however, have developed equipment that eliminates much of the agony. This equipment comes in different levels of complexity and cost. The size and complexity of a project dictates which is most appropriate.
Commonly called “tuckpointers’ grinders,” small disc grinders are indispensable tools for repair contractors who do a lot of work repointing masonry. These electric-powered right angle grinders allow hardened mortar to be cut out quickly and efficiently.
Identify elements of a masonry wall that should be identified in a mock-up panel. Describe how mock-up panels can improve the outcome of a project. Consider criteria of ASTM C216 and their impacts on a project.
Brick with initial rate of absorption (IRA) less than 5gm/min/30 in2 can be used successfully when laid in mortar having low water retention. In this research program, brick with IRA near 1 gm/min/30 in2 and 4 gm/min/30 in2 were combined with seven different mortars.
Outdoor Stairs and brick walls: the good, the bad and the ugly.
For a cavity wall to function properly, water that collects on flashing must be able to drain through weep holes to the exterior of the building. If weep holes do not function properly, water collecting in the cavity can infiltrate to the building’s interior. For proper drainage, cavity walls must be detailed correctly and constructed to keep the cavity clear of mortar droppings and prevent weep hole blockage.
Re-anchoring brick saves money! When wall ties are missing or corroded or brick headers are broken, the exterior brick or portions of it can fall from the building
In a properly designed and constructed masonry wall, mortar joints can last 50 years or more without maintenance. Eventually, though, natural weathering by wind and rain will cause the mortar to erode. Inferior original materials or workmanship, design flaws, or traumatic damage to the building can hasten mortar deterioration.
To an architectural preservationist, the worst scenario imaginable is a masonry wall where the mortar joints surround deep impressions, pockets of eroded brick or stone. This indicates that little or no consideration was given to compatibility when the wall was repointed.
The maximum horizontal spacing between vertical control joints in concrete masonry walls is determined by: the local average annual relative humidity, whether the concrete masonry units are moisture controlled or nonmoisture controlled, as defined by ASTM C 90, the vertical spacing of bed joint reinforcement, exposure to weather.
Moisture entering buildings has the potential to cause problems for the health and well-being of the building inhabitants if the building envelope is not designed and constructed properly. Thus, the flashing of masonry for exterior openings is tremendously important to architects, engineers, and contractors.
When joints are weathered but not badly deteriorated, this technique can stop leaks more economically than repointing.
3 Points of Interest: Major changes in design using steel studs and rigid insulation, tolerance in masonry related to poured concrete foundations, good limestone cap details to be shared and learned.
Before specifying mortar for a project or using it in the field, it is important to understand why the performance of mortar is vital to the successful performance of masonry and how the ingredients in mortar affect its performance.
The purpose of this publication has the following objectives: (1) to offer support for upgrading local building codes that will increase the fire safety of LRMFD’s, (2) to examine the superior performance of masonry and concrete under standard fire test conditions versus that of other types of building construction commonly used in LRMFD’s, (3) to show that masonry and concrete LRMFD construction is not overly expensive as compared to wood frame due to the property insurance savings that are associated with masonry and concrete.
Water in masonry walls creates numerous problems: freeze/thaw fractures, cracks form, efflorescence appears, wall stains, insulation failure, material swelling, wood warp, gypsum decay, metal corrosion, paint peels, mold grows, mildew forms, and odors reek. Much thought is given to warding off wind-driven rain by using wall drainage cavities, flashing, and weep holes.
Utility Brick Bonding
This article illustrates how 1/3 bond is more economical than 1/2 bond when using utility sized brick.
Abuse Resistant Drywall ? Any School Board, which allows a construction manager to sell them on the idea of a guaranteed maximum project cost, should be required to visit previously constructed “guaranteed maximum” school projects. Then everyone could see the extent of damage and associated increases in necessary repair costs.