Last updated July 29, 2026
K-Value
The measurement of the ability of the glass to transmit heat through its thickness when the difference between the temperature of the air on two sides is one degree. The lower the K-Value the better the insulation.
Kerb
A pavement edge. Do not use the US spelling “Curb”.
Kerb-Ramp
A short ramp cutting through a curb or built up to it.
Kerf
A preformed groove in the edge of a ceiling infill unit.
Keystone
The wedge-shaped central piece of an arch.
Kiln
A room or oven-like piece of equipment used to remove moisture and (sometimes) natural oils in preparation for the timber to be used in furniture making or for other purposes. Wood is kiln dried to minimize movement in service and to prepare the surface for the application of various finishes.
Kiln-Dried
Wood that has been dried to resist warping, splitting and cracking.
Knee-Brace
A bracket with an open, triangular shape. Often applied to the eaves of bungalows.
Knot
In timber, the portion of a branch or limb of a tree that appears on the edge or face of the piece.