REAL ESTATE DICTIONARY A I B I C I D I E I F I G I H I I I J I K I L I M I N I O I P I Q I R I S I T I U I V I W I X I Y I Z Results K Back to top key A groove in the top of a footing. keys Little fingers of plaster that squeeze through lath. When they harden, these hold the plaster in place. keystone An angular block centered over a door or window in a header or mantle. kick-out clause A clause in a sales contract that allows a seller to accept one buyer's contingent offer, then back out without penalty if a second buyer makes a better offer. kit home A structure that contains prefabricated components and is put together by a contractor. K Back to top knee wall A wall-like structure that supports roof rafters. knob-and-tube wiring An old-fashioned wiring system that has been replaced by fuses and circuit breakers.