from The American Heritage® Dictionary of the English Language, 4th Edition
- n. One of several horizontal timbers supporting the rafters of a roof.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A longitudinal structural member bridging two or more rafters of a roof.
from the GNU version of the Collaborative International Dictionary of English
- n. In root construction, a horizontal member supported on the principals and supporting the common rafters.
from The Century Dictionary and Cyclopedia
- n. In carpentry, a piece of timber laid horizontally upon the principal rafters of a roof to support the common rafters on which the covering is laid. Also called side timber or side waver. See cut under roof.
For the roof we will require a ridge against the wall of the dwelling house, sash-bars running at right angles to this, a "purlin," or support, midway of these, and a sill for the lower ends.
I got up, and holding tightly to the purlin — for the waves made the masts tremble with their violence — I tried to look around and below me.
One of the main disadvantage of the truss is that the strength and stability of its elements is to be designed by an engineer while the other roof structures, especially the purlin roof, can be built by carpenters and steel workshops themselves.
The purlin roof consists of both rafters and purlins.
Material input low, but requires connectors, fasteners high (requires rafters, posts, struts, purlins and battens) less material input than for purlin roof
The static system of the roof structure as a whole is then no longer a truss but can be a purlin roof (see Section 2.3), a double-hinged arch or bent.
The bay of these 7 × 15 section angelica wood joists has an inter-axis of 56.7 cm and 47 cm on either of the bracing tie-beam of the roof structure; this tiebeam forms part of the joist system and takes up the purlin brackets of the roof overhang of the gutter roofs.
Eaves purlin anchored to the ring-beams on waiting rods laid during the pouring of the ringbeam.
Around the top of the walls a reinforced concrete ring-beam in a lost formwork of earth blocks also serves to anchor the eaves purlin on which restes the lower edge of the steel roofing sheets which then extende beyond the wall.
The attachment of the lower edge of the roofing sheets is reinforced at the level of the eaves purlin, which lays on the top of the verandah posts 'at the end of the ring-beam, by 6 mm diameter rods laid during the pouring of the ring-beam concrete which are then bent round the eaves purlin.