Hard Edge 
Section along the paperbound edge of gypsum drywall, which is strengthened to resist damage. 

Hard Hat 
Hard-shelled headgear with a shock-absorbent interior webbing used to cushion head blows. 

Hard Money 
1. Currency that has wide acceptance, such as the U.S. dollar. Alternately, gold or silver coins, as compared to paper currency. 
2. Actual cash exchanged in a loan. 
3. Term sometimes used to describe extremely high interest rate mortgage loans made to desperate borrowers. 

Hard Oil Finish 
High or moderately gloss interior varnish. 

Hard Water 
Hard water that contains a large amount of minerals. 

Hardboard 
Material made from wood fibers, compressed under heat and pressure to a density of 31 pounds per cubic foot, which are designed to simulate wood. 

Hardener 
Additive used in concrete or any compound to make it set up harder. 

Hardfacing or Hard Surfacing 
Wear-resistant coating of one metal applied by weld overlay to another softer base metal. Alternately it can be applied by insertion of a section of the hardfacing material into a recess in the softer metal. Hardfacing is often used with devices in a high-pressure steam system. 

Hardness 
Measure of a materials resistance to dents or scratches. 

Hardwoods 
Wood from broad leaf, deciduous trees such as oak, walnut, ash, maple or birch, which are used commonly as flooring in homes. 

Hasp 
Locking mechanism consisting of a hinged closure with a slot. A U shaped staple is passed through this slot and a lock is attached to that. 

Hatbanding 
Term which denotes wall paint where some lines appear darker than others, usually cause by use of a roller with a nap that's too thick or by excessive rolling or brushing. 

Hatch
Removable cover over an opening, that serves as an entry to a space. 

Hatchet 
1. A small ax with a short handle. 
2. Hand tool with a nail-driving surface on one end of the head and a blade on the other end. 

Haul 
1. To transport or move with force. 
2. An amount gained, earned or won at one time. 

Haul Road 
Road used for access to a work site. 

Haunch 
1. Either of the sides of an arch from the point of rising to the vertex. 
2. Thickened section of a structure. 

Hawk 
A small, square board with a handle underneath, which is used to hold mortar or plaster. 

Hazard 
Condition that affects the probability of losses or perils occurring, such as flood damage to a house. 

Hazard Insurance 
Homeowner's insurance or fire insurance, hazard insurance covers physical risks such as those from fire or wind. Usually required by lenders for the full replacement value. 

Hazardous Electrical Location Classifications 
Hazard classifications as established by the National Electrical Code: 
Class I - Areas containing flammable gases or explosive/burnable quantities of vapors. 
Class II - Areas containing combustible dust. 
Class III - Areas containing easily ignited fibers or particles. 

Hazing 
Paint defect, which makes the finish surface cloudy. 

HDO 
High-density overlay is a type of plywood, which is finished with a resin-impregnated fiber overlay, which gives it a permanent hard finish, because the overlay material is bonded to both sides of the plywood. Used often for exterior work or wherever material takes a lot of wear, such as cabinets, countertops, etc.