How to Install a Brick Windowsill

Written by charles judd
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How to Install a Brick Windowsill
A brick window sill can dramatically change the look of your home. ( Images)

Installing a brick windowsill around can be a beautiful addition to the look of your home. When installing brick windowsills, it is important to have the proper slope or drainage holes in place. This ensures that your sill does not collect any water that may cause moisture damage to the structure. With special tools and some patience, a proper brick window sill can be installed by most handymen.

Skill level:
Moderately Challenging

Things you need

  • Tape measure
  • Protractor
  • Pencil
  • Brick chisel
  • Brick hammer
  • Weep-hole wicks
  • Mortar mix
  • Water
  • Clean bucket
  • Trowel
  • Level
  • Brick jointer
  • Whisk broom
  • Stiff brush
  • Safety glasses

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  1. 1

    Measure the distance from the window to the outside of your exterior brick wall. Add at least 1 inch to this measurement. The bottom of the brick sill must extend at least 1 inch past the outer surface of the brick wall.

  2. 2

    Lay the brick onto a work surface. Ensure the holes in the brick are facing up. Position the protractor to read a 15-degree angle. Mark the angle on each side of the back of a brick with a pencil.

  3. 3

    Place the brick chisel onto the 15-degree line that you marked on the brick. Strike the opposite end of the chisel with a brick hammer until the end of the brick breaks off.

  4. 4

    Measure across the width of the window flashing. Draw a pencil mark every 16 inches for weep-hole wicks. Place the wicks on these marks horizontally. Ensure that the wicks extend slightly beyond the front of the existing window flashing.

  5. 5

    Mix together the mortar and water in a clean bucket according to the manufacturer's instructions. Use a trowel to mix thoroughly.

  6. 6

    Spread a layer of the mortar mix onto the window flashing.

  7. 7

    Install the bricks onto the wall below the window. They should slope downward away from the window at a 15-degree angle. Spread mortar between each brick to match the existing joint width of the brick exterior wall.

  8. 8

    Use the level to check your work as you go. Ensure the bricks are level and straight.

  9. 9

    Use the brick jointer to smooth the mortar between each brick, forming a rounded mortar joint. Use the whisk broom to sweep off any excess mortar from the surface.

  10. 10

    Allow the mortar to dry completely, according to the manufacturer's instructions. Use water and a stiff brush to clean the brick and mortar once it is completely dry.

Tips and warnings

  • Always wear eye protection when chiselling brick or stone.

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