AY Honors/Masonry/Answer Key
Masonry
1. Name at least six materials commonly used by masons in the erection of walls or buildings.
Primary materials include:
- Brick
- Concrete Block (also known as cinder block)
- Poured Concrete
- Stone
- Glass Block
- Tile
Secondary materials include
- Mortar
- Rebar
- Grout
2. Demonstrate ability to use properly the following:
- PlumbBob.jpg
Plumb Line
- Level1.jpg
Level
- Masonhammer.jpg
Mason's hammer
Plumb line
A plumb line is a string with a plumb bob at the end of it. The plumb bob hangs straight down, so the plumb line can be used to make sure that a wall is perfectly vertical and does not lean in any direction. A perfectly vertical line is said to be plumb.
Line stretcher (chicken legs)
A line stretcher is used for guiding the mason when laying brick or other materials in a straight line. Typically, the mason will build up the corners or ends of a wall first, stretch a line between them, and lay the remaining bricks between them. The line stretcher is often set about a sixteenth of an inch away from the wall so that the bricks do not touch it (otherwise they might push the line out).
Level
A spirit level or bubble level is an instrument designed to indicate whether a surface is level or plumb. Spirit levels feature a slightly curved glass tube which is incompletely filled with a liquid, usually coloured 'spirit' (a synonym for ethanol), leaving a bubble in the tube. Ethanol is used because of its low freezing point, −114°C, which prevents it from freezing in cold weather. Most commonly spirit levels are employed to indicate how horizontal (level) or how vertical (plumb) a surface is.
Trowel
A trowel is used for applying mortar to bricks, blocks, or other material. It is also used for "throwing a mortar line" - that is, laying a line of mortar atop the surface upon which that the bricks will be laid.
S-tool
An S-Tool is more commonly known as a jointer. The purpose of the S-tool is to place the grooves in the mortar between bricks. The concave grooves seen within the mortar lines of bricks are placed there by scraping the S-tool along the mortar well before it sets.
The S-tool should be used sometime between the time that the mortar is placed, and when it begins to harden. If the S-tool is used too late, then it will result in uneven lines throughout the mortar. The mortar will not have a smooth concave surface, and will look very raggedy.
Sometimes an S-tool is not used, and the mortar is placed on in excess; the slapping of the bricks causes it to drip down over the bricks, and it has a very nice effect when the bricks are painted afterwards.
Mason's hammer
A Mason's hammer has one flat traditional face and a short or long chisel-shaped blade. It can thus be used to chip off edges or small pieces of stone without using a separate chisel. The chisel blade can also be used to rapidly cut bricks or cinder blocks.
3. Demonstrate a knowledge of building cement characteristics (know how to prevent sweating, cracking, shrinking, crumbling, and loss of strength).
- Sweating
- Cracking
- Shrinking
- Crumbling
- Loss of strength
4. Make useable mortar and state proper proportions of ingredients (lime, sand, etc.).
There are two basic types of mortar: type N and type S.
Type N mortar is used for interior work and exterior work that is above grade (that is, not buried). It is made by combining:
- Lime (one part)
- Cement (one part)
- Sand (six parts)
Type S mortar is used for below-grade applications such as retaining walls and basements. It is made by combining:
- Lime (one part)
- Cement (two parts)
- Sand (nine parts)
Water is added to either of these mixtures and worked in with a trowel or a hoe until it reaches the desired consistency. Both types can be purchased pre-mixed so the mason need only add the water. Mixing is done on a hard flat surface, often in a wheelbarrow or on a sheet of plywood, but more properly in a mortar box.
