Transcript Latherfinal
Lather
Skill Trades 1201
Introduction
Lathers
Assemble
and install the framework for
gypsum materials (Drywall & Plaster) in
buildings.
Plasters
Two main types:
1. Cement based - Used mainly for outdoors.
2. Gypsum based – Indoors only.
Cement Based
Can be used indoors for areas that
Are likely to become damp and
Require a greater thickness of cover.
Gypsum Based
Used in conjunction with drywall to cover
the interior walls.
Can be powder form which must be mixed
with water, or Premixed and ready for use.
Drywall Joint Compound
Two categories:
1. Drying-type compounds
2. Setting-type compounds
Drying Type Compound
The most common compound
Pre-mixed or Powdered form
Dry via water evaporation
Allow 24 hours for drying
Drying Type Compound
Three kinds of drying type compound:
1. Topping compound:
Final thin coat,
Ease of workability
Drying Type Compound
2. Taping compound:
First coat to capture the joint tape
Second coat as filler
Drying Type Compound
3. All-purpose compound:
Any stage of drywall joint taping.
It is the most commonly used
Setting Type Compound
Dries by chemical reaction
Hardens much quicker (20 mins to 6 hrs).
Harder to sand.
Does not come premixed
Drywall
Drywall
Sheet material made of a sandwich of
gypsum and two layers of paper.
Drywall sizes
Width
4
feet
Length
8,
10 or 12 feet
Commercial builders often use sheets up to 16
feet in length.
Drywall Thickness
5/8 inch panel:
Considered
fire resistant.
Drywall Thickness
1/2 inch panel:
Most
commonly used
General purpose for walls and ceilings.
Drywall Thickness
1/4 - 3/8 inch panel
Used
sometimes to overlay existing, older
walls in order to make it smoother.
Is also used to make curved walls.
Types of Drywall
Standard drywall sheets
Have
tapered long edges and the short ends
are squared off.
One face is rough, and one face is smooth,
for painting and papering.
Types of Drywall
Moisture Resistant Board
Also
known as Greenboard.
Used in interior areas such as bathrooms and
basements where added moisture resistance is
needed.
Types of Drywall
Fire Rated
5/8
drywall.
Used between apartments.
Fasteners
Screws
Type
W bugle head screws
Has a course thread and provides excellent holding power in
wood.
Screws cont’d.
Type S bugle head screws
Has
a tip that drills its own hole in metal studs in
walls.
Fasteners
Nails
Ringed-Shank
nails
The rings provide better grip.
Provides 50 to 100 percent greater holding power than a
smooth-shank nail.
Drywall Tape
Drywall tape is used to cover or seal the joins
between drywall edges.
Drywall Tape
Types
Flexible Paper
The paper tape is applied into wet plaster.
Crease in centre so it can be folded.
Drywall Tape
Fiberglass Mesh Fabric - The mesh is
usually self adhesive.
Drywall Tools
6. Sanders: used to smooth the plaster before paint is applied.
Installing Drywall
Drywall is always fastened to the ceiling
before the walls.
Drywall is fastened to the “studs” of the
walls.
Ceiling
Walls