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

Materials Materials (per 100 s.f. face area
Concrete Block Brick
8 x 16 8 x 18 5 x 12 2.67 x 4 x 8
No. of Units 112.5 100 240 675
Mortar (Cu. Ft.) Face shell bedding 2.3 2.2 3.6 7.2
Mortar (Cu. Ft.) Face shell and web bedding 3.2 3.0 2.5 7.2

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

Block Productivity

Labor Hours per 100 Square Feet
Wall Thickness 6” 8”
Type of Work Mason Laborer Mason Laborer
Simple foundation 4.5 6.0 4.0 – 7.5
Foundation with several corners and openings 5.0 7.5 5.0 – 7.5
Exterior walls to 4’ high 4.0 6.0 4.0 – 6.5 4.5 6.0 5.0 – 7.5
Exterior walls 4’ – 8’ 4.0 6.5 4.5 – 7.0 4.5 6.5 6.0 – 9.0
Exterior walls above 8’ 5.0 9.0 7.0 – 10.0 5.0 7.0 7.0 – 10.0
Interior partitions 3.5 6.5 4.5 – 7.5 4.5 6.0 5.0 – 7.5

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

Labor Hours per 1,000 Standard Size or Modular Bricks
Type of Bond Mason Laborer
Common 10.0 to 15.0 11.0 to 15.5
Running 8.0 to 12.0 9.0 to 13.0
Stack 12.0 to 18.0 10.0 to 15.0
Flemish 11.0 to 16.0 12.0 to 16.0
English 11.0 to 16.0 12.0 to 16.0
    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

Accessories Unit Labor Hours
Wall Reinforcing 1,000 l.f. 1.0 to 1.5
Lintels – Precast Concrete

(up to 300 pounds)

100 l.f. 4.5 to 7.0
Coping, Sills, and Precast Concrete (up to 150 pounds) 100 l.f. 5.0 to 8.0
Wall Ties 100 Pieces 1.0 to 1.5
    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

 

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