| Purlin | Longitudinal roof timber supporting rafters between apex and wall plate. |
| Butt purlin | Purlins joined end to end or into the end of a bay. |
| Clasped purlin | Purlin held against the principal rafter by a collar,queen strut or raking strut. |
| Collar purlin | Plate supported on crown post and bearing the collar. |
| Staggered butt purlin | Purlin in one bay out of line with purlins in adjacent bays. |
| Dragon beam | A horizontal timber which runs diagonally into a corner angle, into which floor joists are tenoned. |
| Collar | Transverse beam connecting the mid-points of the sloping rafters of a pitched roof. |
| Crown post | Vertical timber standing on tiebeam and supporting collar purlin. |
| King post | Post standing on a tie beam or collar to support a ridge piece. |
| Queen struts | Paired struts between tie-beam and collar, not supporting a longitudinal timber. |
| Raking Queen struts | Paired struts at an angle to the tie-beam, framed into the principal rafter. |
| Rafter | Sloping parallel roof timbers supporting tiles or other cladding material. |
| Ridge piece | Longitudinal timber at apex of roof. |
| Sans-purlin | Roof with no purlins (q.v.). |
| Tie beam | Beam connecting the two slopes of a roof across at its foot, usually at wall plate level. |
| Truss | Framework across a roof at intervals carrying longitudinal timbers |
| Wall plate | A timber laid along the top of a wall to receive the ends of rafters, tie beams and ceiling joists.
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