created by michael martin 13/9/04 – reviewed june 2010
TRANSCRIPT
Rafter & Creeper spacing
You can either
• Mark your creepers on pattern rafter, or
• Calculate their true length
Some people refer to this as a gambrel end Can be finished with
◦ Fibre-cement sheets, or ◦ Timber cladding, or◦ Other desired finish
Must be correctly flashed
Dutch Gable on a hipped roof
Small Spans Small roofs can be
framed on top of hip like shown (handout)
Larger spans are approached differently, which we’ll look at now (handout)
Set out and ridge length
• Size of gablet is determined by the number of rafter spacings past the centering rafters
• Set out of centering rafters remains the same as for the hipped roof
Set out & Ridge continued
Length of ridge for hip initially the same (handout), then rafter spacings added
If at one end only, add three rafter spacings
If at both ends, then add six rafter spacings
The easiest way to position the pitching plate and determine length of jack rafter, is to set it out on a pattern
Looking at a centre line plan view, of this roof, is the easiest way to determine this
Shown on the next slide
Lengths and position
Length for pattern
This example has a two rafter overhang and is also the one you will make
Set-out gathering point
• The jack rafter can be set out on the pattern, just as you do the creepers
• 1st count additional rafters (two)
• so you can step two spacings down from centre line on pattern
• Then allow for ½ thickness of rafter after that
• This point is the length of your jack rafter
• Cut this and use as a set-out for pitching plate
One rafter spacing
Two rafter spacing
½ rafter
Pitching plate continued
Use cut jack rafter to mark position for pitching plate
Pitching plate is located at this position