an explanation of roofing framing for assessment

I cannot find the photos easily here to back up my work but I can show you on Drive. I am going to explain the times we have done roof framing and what we did. First of all you have to take delivery of the pre made trusses.  We have done both timber and steel trusses.  In both cases you need space to put them safely and somewhere where they will not be damaged or warped. Timber should be completly flat and wrapped after and steel as well. You then need a lift plan this should be a written and agreed about task analysis. With timber trusses it is likely you will need machinery to lift into place with residential steel trusses you could lift with manpower but a plan needs to be in place. The trusses will be marked out already usually 900 centres but we would Check the plans and specs. The best way of marking out is 922 x back and then 900 running measurements. I marked out the roof at the Warkworth primary like this over 30 metres. Once trusses are in place you will need to fix them off correctly and also temp brace them. Once trusses are in place the next step is to mark and chalkline purlins off the top off my head I think they are usually 600 centres but we would check the plan. Once purlins are all secure you can remove all temp braces and install any uplift and tie down hardware. Thought should be considered for any load bearing walls to also make sure they are braced and will not be impacted by extra weight and movement. We usually use blue screw purlin screws for timber and manafactured screws like Wurth screws for steel.