Strange Purlin Support

[scruffybiker]

I noticed in a relatives loft a purlin support method I've never seen before. The property is Victorian era. The purlins sit on brick corbels each end. But instead of the usual vertical struts (as the purlin sits verticle.) supporting the purlin along its span there are 2 x 4" braces that sit directly under the purlin spanning from rafter to rafter like Colar ties but support the purlin along its span. There are only one of these braces every quarter length along purlin. anyone else seen a method like this? seems to be doing its job as the purlin is only 5x3" and spans 5m.

 

[scruffybiker]

like this but the purlins in question are in one piece & sit verticle . The purlins also have a 2x4" attatched with a birdsmouth cut on the top side of purlin.

//www.diynot.com/diy/threads/more-loft-question-s-collar-type-support.239721/