Extended Coverage 
Protection over and above that of a standard policy or warranty and covers things that might otherwise be excluded. 

Extended Plenum Ducting 
HVAC systems use this type of ducting with a large central duct with smaller branches routed out. 

Extension 
The granting of additional time to conduct a specific act. Alternately, a part that forms a continuation or addition. 

Extension Agreement 
Written agreement between parties to extend the terms of a document. 

Extension Bit 
To lengthen the reach of a drill bit, this metal rod extension with grippers is fitted into the drill motor chuck. 

Extension Cord 
Portable electrical cord, in various lengths, that is used to access a source of electricity not readily available. 

Extension Line 
Method of locating a drawing dimension in an area different from the actual place by use of an extension line because of crowding in the drawing. 

Extension Ruler 
Ruler that folds into itself and can be extended to measure. 

Extensive Margin 
The broad use of credit to purchase a security. The current (1994) rules of the New York Stock Exchange (NYSE) state that an investor must have at least 50% of the cost of a security in cash. An investor using extensive margin would be using the maximum credit available to purchase securities increasing the risk should the market value of the purchased securities decline and trigger a broker's call for additional cash to mark the margin to the market value. 

Exterior 
Generally referring to the outside of a building. 

Exterior Ceiling Panels 
Water-resistant panels, made with a core that is wrapped with water repellent being facing paper, which are used outside where there is limited exposure to the elements. Joints are finished off with joint tape and water resistant joint compound and the panels can be used without decoration. Panels are 4 feet in width and eight or twelve feet in length with either ½" or 5/8" thickness, with the 5/8" thickness being fire-resistant rated. 

Exterior Door 
Door used in a doorway, which has exposure to the elements on the outside. 

Exterior Finish 
The external covering finish of a structure, which protects it from the elements. Exterior finish material including shingles, siding and paints are designed to resist severe weathering effects as well as providing decoration.

Exterior Wall 
Outside wall of a structure which is normally insulated to protect the interior of the structure. Exterior walls can also be load-bearing walls. 

External Combustion Engine 
Engine that obtains it power by a combustion process outside the engine. 

External Corner 
Also referred to as an outside corner, this corner protrudes into a room. 

Extreme Fiber in Bending 
Resistance of lumber to an applied load. 

Extrude 
The forming or shaping of a material by forcing it through a small opening. 

Extruded Metal 
Metal that has been forced through a die to shape it. 

Extrusion 
The process of forming or shaping a material by forcing it through a small opening. 

Eye 
Hole in the head of a tool. Loop of metal or thread. Opening which allows an object to be passed through. 

Eyebolt 
Threaded bolt with a portion bent into an eye at one end. 

Eyelet 
Reinforced hole. 

Eye Protection 
Safety glasses used to prevent foreign object from entering into an eye. 

Eye Screw 
Shank end of a wood screw bent into an eye.