Learn how Barap Bolts were used to support roof structures in difficult situations.
How Barap bolts & roof support were an essential part of roof construction in the 70’s. QBIS.
What is a Barap bolt?
- A metal rod with a thread at each end.
- Fitted through one or two u shaped bracket located in the middle or a third of distance from the ends
- Attached by bolts to members of the roof structure.
- A nut attached to the threaded end of the rod was tightened up, this would place pressure at the mid point where a steel bracket was inserted to support the area required.
Purpose of a Barap Bolt also type of roof construction where they were used.
- To allow support of a roof structure where support off an internal wall was not possible.
- Often used in the construction of hand-cut roofs, where support off internal walls could not be achieved.
Barap bolts & roof support. How Barap Bolts work.
By tightening nuts attached to threads at each end of a rod. This shortens its length and places pressure that allows support, where struts are positioned.
These were a simple but effective means of roof support where conventional methods could not be achieved.
Improperly fitted Barap bolts.
Brackets that have been attached to the rafters have no support below them, this is causing the ridge-beam to bow sideways. This can also cause timber to fracture from pressure pulling downwards when the bolt is tensioned to achieve support where it is required.
How to fit a Barap Bolt correctly.
- Support must be fitted below brackets where they are bolted to any timber member.
- Supports below the brackets must be propped off an appropriate sized beam or off a wall, directly below where they are attached.
- Without proper support below the bolted bracket, fracturing of the timber often occurs when the bolt is tensioned.
Barap bolts and roof support, related roof information:
QBIS: Roof components and location
Roof Technical Information
Tafe: Building terminology
QBIS: Barap Bolt roof supports