Masonry Works In Construction

Estimating in Building Construction

Masonry Includes

• Block
• Brick
• Clay tile
• Stone
• Lintels
• Reinforcing
• Weep holes
• Precast concrete
• Mortar
• Scaffolding
• Temporary enclosures

Concrete Block Patterns

Stone Pattern

Brick Pattern

Mortar Joints

Concrete Masonry

• Comprises all molded concrete units
• e.g. concrete brick, hollow and solid blocks, decorative blocks

Concrete Blocks

• Materials bid by the block
• Keep block types separate, heavyweight or lightweight
• Say 112 Units per 100 square foot of wall For nominal size 8’’ x 8’’ x 16’’ block Units per sq. ft. = 144/(8’’ x 16’’)
• = 1.125 block per sf
• Labor bid by the square foot
• Strength and absorption (ASTM)
• Corners should be taken once
• Deductions for all opening in excess of 10 sf.
• Add allowances for waste and breakage

Separate Masonry By

• Size
• Shape
• Colors
• Bond or pattern
• Shape of mortar joints
• Mortar color
• Other (e.g. fire rating)

Material Requirments

Add waste for blocks and bricks (5 to 100%)

Block Productivity

Clay Masonry

• Includes brick and tiles
• Brick is considered a solid unit if it contains cores less than 25% of the cross- sectional area of the unit.
• Facing tiles are available either glazed or unglazed
• Ceramic glazed units are available in wide variety. They are easy-to-clean

Bricks

• Brick is sold by the thousand units
• Bid by the 1,000 bricks
• Labor cost is affected by length of straight wall, windows, piers or anything else that might slow the mason’s work such as weather.

Bricks Productivity

Tiles

• Calculate area and then number of units or tiles

Stone Masonry

Used for

• • Exterior walls
  • Walkways
  • Riprap
  • Veneer for walls

Include

• • Mortar (cu. ft.)
  • Ties
  • Flashing (sq. ft.)
  • Lintels (lf.)

Estimated by the area in sq. ft. with the thickness given

Cut stones have 2 to 4 % of the total volume as mortar

• Dressing and cutting of stone require skill on the part of the mason
• Large pieces may require crane for lifting

Mortar

• Made from:
  • Portland cement
  • Mortar sand
  • Hydrated lime
• Thickness of mortar joints 3/8’’, ¼’’, ½’’
• Use two mixers when using two colors
• Labor cost is included as part of the masonry units

Accessories

• Masonry wall reinforcing comes in a wide variety of styles and wire gauges
• Control joints
  • A vertical joint from top to bottom. Reinforcing should not cross over control joint
• Wall ties
  • Connect inner and outer wythes (Fig 11.17)
• Flashing
  • Diverts moisture to the exterior. Materials include copper, aluminum, copper and polyethylene, plastic sheeting, elastomeric compound, copper and fabric (Fig. 11.18)
• Weep holes
  • Drain moisture from the wall
• Lintels
  • Horizontal member that supports masonry
• Sills
  • Members at the bottom of the windows

• Coping
  • Cover top course of wall (see Fig. 11.18)

Labor Hours for Installing Accessories

Reinforcing

• Rebar
  • Placed in masonry walls, beam block and grouted
  • Bid same as rebar in concrete
• 
• Mason’s hand tools
• Mortar boxes
• Mortar mixer
• Hoses
• Shovels
• Wheelbarrows
• Mortar tubs
• Scaffolding
• Hoisting equipment
• Forklifts
• Lift trucks
  • Temporary enclosure
  • Temporary heat
  • Common practice to heat the water to maintain temperature