Dado – A groove cut into a board or panel intended to receive the edge of a connecting board or panel.

Damper – A metal “door” placed within the fireplace chimney, used to control the amount of airflow through the fireplace.

Dampproofing  – The black, tar like waterproofing material applied to the exterior of a foundation wall.

Daylight – The end of a pipe (the terminal end) that is not attached to anything.

Dead bolt – An exterior security lock installed on exterior entry doors that can be activated only with a key or thumb-turn. Unlike a latch, which has a beveled tongue, dead bolts have square ends.

Dead light – The fixed, non-operable window section of a window unit.

Deck (noun)– A raised surface. The most common use of this term in residential construction describes an outdoor area for entertainment or access to a door to gain entry to a dwelling. In commercial architecture, this term is also used to describe raised plains of wood, concrete, metal glass or other like surfaces.

Deck, decked (verb)- To install the plywood or wafer board sheeting on the floor joists, rafters, or trusses.

Dedicated circuit – An electrical circuit that serves only one appliance (ie, dishwasher) or a series of electric heaters or smoke detectors.

Default – Breach of a mortgage contract (not making the required payments).

De-humidistat – A control mechanism used to operate a mechanical ventilation system based upon the relative humidity in the home.

Delamination – Separation of the plies in a panel due to failure of the adhesive.  Usually caused by excessive moisture.

Design & Load Data Abbreviations– Initials used in design tables and calculations to determine building methods and standards:

  1. General:
    1. CS, Case Studies
  1. Snow Load Criteria:
    1. Pg, Ground Snow Load.
    2. Pf, Flat-roof Snow Load.
    3. Ce, Snow Exposure Factor.
    4. Is, Snow Load Importance Factor.
    1. Ct, Thermal Factor.
    2. Pd, Drift Surcharge Load(s).
    3. w, Width of Snow Drift(s).
  1. Wind Design Criteria:
    1. Vult,  Ultimate Design Wind Speed (3-second gust).
    2. Vasd, Nominal Design Wind Speed, as determined in accordance with Section 1609.3.1.
  1. Earthquake Design Criteria:
    1. SDC, Seismic Design Criteria.
    2. 1e, Seismic Importance Factor.
    3. SS and S1, Mapped Spectral Response Acceleration Parameters.
    4. SDS and SD1, Design Spectral Response Acceleration Parameters.
    5. CS, Seismic Response Coefficient(s).
    6. R, Response Modification Coefficient(s).
  1. Construction Methods for Braced Wall Panels (List and Figure at Table R602.10.6.4):
    1. ABW, Alternate Braced Wall panels (R602.10.6.1).
    1. PFH, Portal Frame with Hold-downs (R602.10.6.2).
    2. PFG, Portal Frame at Garage door openings in Seismic Design Categories A, B and C (R602.10.6.3).
    1. CS-PF, Continuously Sheathed Portal Frame, (R602.10.6.4).
    2. BV-WSP, Wall bracing for dwellings with stone and masonry Veneer in Seismic Design Categories D0, Di and D2.  (R602.10.6.5).
    3. See

DF/L #2 – Species Douglas Fir or Larch, Grade #2.

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.

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.

Door operator– An automatic garage door opener.

Door stop– The wooden style that the door slab will rest upon when it’s in a closed position.

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 glass– Window or door in which two panes of glass are used with a sealed air space between.  Also known as Insulating Glass.

Double hung window– A window with two vertically sliding sashes, both of which can move up and down.

Down payment– The difference between the sales price and the mortgage amount. A down payment is usually paid at closing.

Downspout– A pipe, usually of metal, for carrying rainwater down from the roof’s horizontal gutters.

Drain tile– A perforated, corrugated plastic pipe laid at the bottom of the foundation wall and used to drain excess water away from the foundation. It prevents ground water from seeping through the foundation wall. Sometimes called perimeter drain.

Draw– The amount of progress billings on a contract that is currently available to a contractor under a contract with a fixed payment schedule.

Drip– (a) A member of a cornice or other horizontal exterior finish course that has a projection beyond the other parts for throwing off water.(b) A groove in the underside of a sill or drip cap to cause water to drop off on the outer edge instead of drawing back and running down the face of the building.

Drip cap– A molding or metal flashing placed on the exterior topside of a door or window frame to cause water to drip beyond the outside of the frame.

Dry in– To install the black roofing felt (tar paper) on the roof. Also used to denote the stage of construction where a structure is protected from weather.

Drywall (or Gypsum Wallboard (GWB), Sheet rock or Plasterboard)– Wall board or gypsum- A manufactured panel made out of gypsum plaster and encased in a thin cardboard. Sometimes 1/2″ thick and typically manufactured in 4′ x 8′ or 4′ x 12′ sizes. The panels are nailed or screwed onto the framing and the joints are taped and covered with a ‘joint compound’. ‘Green board’ type drywall has a greater resistance to moisture than regular (white) plasterboard and is used in bathrooms and other “wet areas”.

Ducts– The cooling and/or heating system. Usually round or rectangular metal pipes installed for distributing warm (or cold) air from the furnace to rooms in the home.  Also a tunnel made of galvanized metal or rigid fiberglass, which carries air from the heater, cooler or ventilation opening to the rooms in a building. Flexible plastic tubes are also available and mainly used in high velocity systems.

Due-on-sale– A clause in a mortgage contract requiring the borrower to pay the entire outstanding balance upon sale or transfer of the property.

Dura board, dura rock– A panel made out of concrete and fiberglass usually used as a ceramic tile backing material. Commonly used on bathtub decks. Sometimes called Wonder board.

Dwelling- Per the ICC, “Any building that contains one or two dwelling units used, intended, or designed to be built, used, rented, leased, let or hired out to be occupied, or that are occupied for living purposes.

Dwelling Unit- Per the ICC, “A single unit providing complete independent living facilities for one or more  persons, including permanent provisions for living, sleeping, eating, cooking and sanitation.

DWV (drain-waste-vent)- The section of a plumbing system that carries water and sewer gases out of a home.

Last updated May 18, 2019