The following notation is often used in timber frame drawings and shows how the standard mortise and tenon notations relate to their associated joinery parts. Note the black triangle which indicates the reference face and points to the reference edge.

## Distance from Reference Face/edge

### Tenon Notation

#### Distance from Reference Face

The distance of the tenon cheek from the reference edge. This measurement is also the depth of the tenon shoulder from the reference face. In the example above the distance is 2 inches. This is the same measurement from the reference edge to the side of the mortise (depicted below).

### Mortise Notation

#### Distance from Reference Face

The distance from the reference edge is where the side of the mortise layout begins and equals the mortise shoulder depth. In the example above the distance is 2 inches..

## Housing Length/Depth

### Tenon Notation

#### Housing Length

In a fully housed tenon, the full section of the tenoned member needs to be reduced to fit withing the respective housing. In the example above the housing length is 1″ long.

### Mortise Notation

#### Housing Depth

The housing depth is given as a nominal measurement. On reference faces the nominal depth equals the actual depth cut. On non-reference faces the depth cut is the difference between the Nominal timber – actual timber depth – the nominal housing Depth. Consider the example 1/2″ housings cut in a 8 x 8 timber that measures 7 7/8 (depth A) x 8 1/4 (depth B). Depth A would equal 8″ – 7 7/8″ – 1/2″ = 3/8″ housing depth. Depth B would equal 8″ – 8 1/4″ – 1/2″ = 3/4″ housing depth.