Stucco

From Open Source Ecology
Jump to: navigation, search

How to Make Stucco

Instructional Video

  • Fill a 5 gallon bucket with 2 shovels of clay
  • Add water and mix evenly using a drill and mixing bit.
  • Add a large cup of portland cement and add half of a large cup of lime (calcium hydroxide).
  • Add water and mix evenly.
  • Add 3 shovels of sand
  • Add water and mix evenly until the consistency becomes a bit thicker than a milkshake.

Note: it is imperative to mix well such that the stucco is smooth without chunks. Avoid rocks when putting in the clay and sand- both chunks and rocks interfere with the stucco application process.

How to Apply Stucco

  • Staple sheets of plastic netting onto the wall. This aids the structural durability of the stucco layer.
  • Spray the wall with a light layer of water. This wets the wall surface for greater adhesion to the stucco layer.
  • Transport the stucco from the bucket to the hand tray
  • Let the long straight edge of the hand tray touch the wall both in preparation for the stucco application and to catch stucco that falls during application.
  • Use a straight-edge trowel to send the stucco from the hand tray to the wall right above the tray. Apply in long, even strokes to produce a thin layer of stucco. Thin layers are less prone to cracking because thicker layers experience faster drying on the outside exposed surface than the inside insulated surface; because stucco contracts when dried, the outside separates and forms cracks while the inside remains relatively unchanged in volume. Thinner layers experience more even drying hence do not crack as often or as seriously.

Notes: It is critical to cover the entire wall and its junctions, especially at the base where the blocks meet the concrete (because the base junction is under the most load). Multiple thin layers of stucco may be necessary depending on the severity and frequency of cracks that form during the drying process.