Dielectric Strength
The maximum voltage a dielectric (nonconductor) can withstand without fracture.
Dimensional Lumber
Lumber from 2 inches (50.8 mm) up to, but not including, 5 inches (127 mm) thick and 2 inches (50.8 mm) or greater in width.
Disconnect
A large (generally 20 Amp) electrical ON-OFF switch.
Discount rate
A mortgage interest rate that is lower than the current rate for a certain period of time, e.g. 2.00% below variable rate for 2 years.
Direct Current (DC)
Electricity that flows in one direction.
Dioxin
According to the World Health Organization, dioxins are some of the most potent toxins known to humans, with no known safe limit for exposure and a strong propensity for bioaccumulation. In addition, dioxins are highly persistent in the environment. https://healthymaterialslab.org/tool-guides/hml-resources
Dewatering
Pumping subsurface water from an excavation to maintain dry and stable working conditions.
Diaphragm
A horizontal roof or floor structural element designed to resist lateral loads and transmit them to shear walls (vertical resisting elements).
Disclosure
The reporting by manufacturers about product ingredients, impacts, or other attributes to the public or to third parties. https://healthymaterialslab.org/tool-guides/hml-resources
Diffuser
A circular, square, or rectangular air distributing outlet, usually in the ceiling, that has members to discharge supply air in several directions, mixing the supply air with the secondary air in the room.
Double Glazing
Two parallel sheets of glass with an air space in between.
Door Buck
Structural element of a door opening. May be the same element as the frame if frame is structural, as in the case of heavy steel frames.
Double-Hung Window
Window sash that slides vertically and is offset in a double track.
Dormer
An opening in a sloping roof, the framing of which projects out to form a vertical wall suitable for windows or other openings.
Double hung window
A window with two vertically sliding sashes, both of which can move up and down.
Double glass
Window or door in which two panes of glass are used with a sealed air space between. Also known as Insulating Glass.
Doorjamb, interior
The surrounding case into which and out of which a door closes and opens. It consists of two upright pieces, called side jambs, and a horizontal head jamb. These 3 jambs have the "door stop" installed on them.
Double Tees
T-shaped precast floor and roof units that span long distances unsupported.
Door stop
- The wooden style that the door slab will rest upon when it's in a closed position.
Door operator
- An automatic garage door opener.