Chapter 6: Measuring Masonry Work

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Chapter 6
Measuring Masonry Work
Objectives
• Upon completion of this chapter, you
will be able to:
– Explain how masonry work and associated
items are measured in a takeoff
– Explain how masonry items are classified
in the takeoff process
– Measure masonry items from drawings and
specifications
Objectives (cont’d.)
– Use conversion factors to calculate
quantities of bricks, blocks, and masonry
mortar
– Complete a manual takeoff of masonry
work and associated items
– Complete a computer takeoff of masonry
work using Excel spreadsheets
Masonry Work Generally
• Includes construction with:
– Clay bricks
– Concrete bricks and blocks
– Clay tiles
– Natural and artificial stone
• Typically performed by subcontractors
Measuring Masonry Work
• Measure “net in place”
• Calculating masonry units:
– Two-stage process
• Area of masonry is measured
• Standard factor is applied to determine number
of masonry units
– A number of other units are measured
• Detailed in drawings or described in
specifications
Brick Masonry
• Bricks:
– Made of different materials
– Manufactured by different methods
– Used in many ways
• Influential factors:
– Price of masonry
– Measurement: sizes and pattern
Concrete Blocks
• Variables to
consider:
– Sizes
– Thickness of joints
• Bond beams
– Measured as “extra
over” blockwork
Figure 6.1
Typical Concrete Block Sizes
(Delmar/Cengage Learning)
Figure 6.2 Nominal and Actual Block Thicknesses
(Delmar/Cengage Learning)
Conversion Factors
• The Building Estimator’s Reference
Book
– States number of “standard bricks” per
square foot of wall for different:
• Wall thicknesses
• Joint thicknesses
• Various bonds
Measuring Notes—Masonry
• Generally:
– Measure quantities “net in place”
– Separately measure circular masonry work
– Include scaffolding and hoisting
– Measure separately by category
– Measure and enumerate several additional
items (listed on page 144)
Measuring Notes—Masonry
(cont’d.)
• Some additional considerations:
– Brick masonry
• Measure in units of bricks
• Separately measure facing bricks
– Concrete block masonry
• Enumerate units stating type and size of blocks
• Separately enumerate special units
• Measure in cubic yards or cubic meters
Examples
• Masonry work—house (brick facings
alternative)
– Takeoff shown as Figure 6.3a
• Masonry work—office/warehouse
building
– Takeoff shown as Figure 6.4
Figure 6.3a
House Example—
Masonry Work
(Delmar/Cengage Learning)
Figure 6.3b
Brick Facings
Alternative—Details
(Delmar/Cengage Learning)
Figure 6.3c Brick Facing—Detail at Foot of Facings (Delmar/Cengage Learning)
Figure 6.4
Office/Warehouse
Example—Masonry
Work (Delmar/Cengage
Learning)
Figure 6.4
(Continued)
Summary
• Masonry work
– Includes construction with clay bricks and
tiles, concrete bricks and blocks, etc.
– Typically performed by subcontractors
– Several items are measured during takeoff
– Quantities of masonry units are measured
net in place
– Classified by types of units and use
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