Hi guys, I'm putting a solid lean to roof on my conservatory with , 120mm by 47mm joists over a span of 3m from bolted on wall beam , covered in OSB board then synthetic roof shingles (keep weight down). Just wondering how far apart joists should be. Is it 600 centres like floor and roof or can I go wider , I'm planning on putting noggins in and then plasterboarding internal. Regards in advance
that's a very skinny timber - I'd not go any lower than 145 - even 195 - and put a rubber roof on it and don't be tempted to fill between the joists with insulation - and don't forget the VCL and and ......
Sorry Mark8828..Ignore my comment re- the TRADA Span tables, I'll leave it to the self proclaimed expert on here, to advise you.
This is a local council to me guide. http://www.broxbourne.gov.uk/environment_and_planning/building_control/timber_span_guide.aspx
lol thats true, its the stud wall that I do 450's at so I can use full boards, I miss-read the thread your right with 400 for the ceiling