Baluster: One of a series of vertical supports used between posts of a
railing. Also called a spindle.
Building Codes: Regulations detailing accepted materials and methods of
building, such as the size of the deck, setback distances, railing and stair
construction, footing depths, fastening methods, lumber types for certain deck
components and fence or screen height around the deck. Usually adopted by city,
county, or state building departments; most counties have local building codes.
Cantilever: A construction method that involves extending the joists
beyond the support beam or the support beam beyond the posts.
Cap Rail: The top horizontal piece of a railing, usually placed to
give it a finished appearance.
Composite Decking: Deck boards manufactured from wood fiber and
plastic to form a profile which requires less maintenance and generally
has a longer lifespan than natural wood.
Concentrated Load: The application of a relatively large force
on a relatively small area.
Dead Load: The weight of the structure itself, which includes the
plank system, support structure and any railings, built-in benches and
other permanent features.
Expansion and Contraction: Boards expand when they heat up and
contract when they cool down. Must be accounted for when spacing deck boards.
Fascia: The boards used to cover rim joists and end joists. Also
Fasteners: Generic term for nails, bolts, screws and other connecting
Footing: The below-ground support of a deck's post, usually made from
Grade: A designation given to lumber indicating the amount of flaws and
knots typically found in the wood. Example: construction common (aka con-common)
is a grade of redwood containing sapwood; construction-heart (con-heart) contains
virtually no knots or blemishes. Inset: An area of a deck that has been cut
out to accommodate decorative and landscape elements such as trees and
Joist Hanger: A pre-manufactured metal piece typically attached to a
ledger or beam to support a joist. Joist hangers should be galvanized.
Joists: Horizontal framing members that support decking; a system of
sub-deck structural elements located directly beneath the deck boards,
commonly using 2 x 6 or 2 x 8 lumber.
Ledger: A length of board, that is horizontally attached to the side of a
house and holds up one edge of a deck.
Linear Feet: The total length of required lumber. For example,
three 8-foot-long 2x4s and four 6-foot-long 2x4s both would be described
as 24 linear feet of 2x4s.
Live Load: The amount of weight a deck is designed to support.
Most deck designs call for a live load of 60 pounds per square foot.
Low-Voltage Lighting: Commercially available lighting systems
that use a transformer to reduce the needed electrical current.
Nominal Dimensions: The label given to a standard piece of
lumber. For example, 2x4 is the name for a rough- cut piece of about
2x4 inches. It is then finished by planing and sometimes sanding it
down to its actual dimensions (1 7/16" x 3 1/2").
On Center: A method of measuring distance between two structural
members, such as joists, where you measure from the center of one member
to the center of the other. The distance between the center of each
joist, commonly 16" or 24". Joists spaced 16" on center are actually 14-1/2" apart.
Pier Block: A masonry post. Piers often serve as above-grade
footings for posts and often are made of pre-cast concrete.
Post: The vertical structural element that rests on the footing
and supports the beam.
Post Anchor: A metal piece attached to or imbedded in the footing
that attaches the post to the footing and keeps the post from being
exposed to moisture in the ground.
Post Cap: A small piece of material (often wood) attached to the
top of the post to cover the post's wood grain and protect the post
from the weather. Can be made of many materials including metal,
Injection-molded plastics, even decorative glass tops for round and square posts.
Pressure Treated Wood: Wood subjected to a high pressure
treatment of chemicals as a preservative.
Rise: The vertical distance from one stair tread to another.
Riser: The vertical piece between two stair steps.
Shade Structure: A structure built above decks, usually of posts
and lattice, to provide a shaded area on the deck.
Span: The distance between supports.
Structural Integrity: A structure's uncompromised ability to safely
resist the required loads.
Sub-Structure: The deck construction that is located below, and
supports the deck boards and railing system. Components include joists
and hangers, ledgers, rim joists, beams, posts, anchors and footers.
Wind Load: The lateral pressure on a structure in pounds per
square foot, due to wind blowing in any direction.