What did you mean by " I don't see any bracing in the log direction either."? I like your idea of the 75x75 running up the length of each rafter. How much did your steel structure cost in the end? Was it from Stratco etc. The rafters are spaced at approx 1290mm, as it is an older house there is no truss work like the newer houses - just looks to be very minimal compared to them (in my own opinion). The house in question is a 1928 bungalow with double brick walls. That doest mean I would not choose steel in the end though, we have had a quote from a company here in SA that deals with Fielders and they quoted a DIY kit for $8200, it comes with most everything except concrete for the footings. Im not against steel but I prefer the look of timber, a solid bulky look. This project is more than sizing timbers. I don't see any bracing in the log direction either - you have something in mind?Īlthough this roof may hold it'self up have you also taken into account it holding it'self down - you may need additional rods into the footings at the connection to the existing roof - this is a big parachute don't forget.Ĭheck with your council that you can get away without having an engineer design and certify this - it seems big compared to most awnings in the spans you are having 10m ridge span then bearing mid-span onto a 5.5m span each end will create large loads locally and must be carried down to the footings -similarly must be anchored down so it does take off and take your house roof with it. I have just added a 7 x 7m awning to my roof and to attach it similar to yours I put 75 x 75 steel angle to the top chord of the existing trusses to allow the load on the end of the eaves. Have you considered whether the existing roof can take this sorta load at the tips of the eaves. Would it be possible to use hardwood for this design and also keep the costs similar to the price of LVL? What I wanted was a chunky look and wood gave me this (I dont mind the steel pergolas from Stratco etc) and reason I originally went with LVL was that I wanted a 'cathedral ceiling' with a clean look - no collar/rafter ties, this seemed to be the only solution in timber for the 10m span. Would I be able to do without the pryda minigrips and joist hangers if i route out a 5-10mm space for the rafters to sit in and skew nail them in only (still using strapping for the top connection), I would prefer the look of this compared to the pryda connections? I have a question regarding the 'rafter to ridge' and 'rafter to beam' connections: Using pryda joist hangers (180x40) to brace the rafters to the side beams. He was happy with the fixing methods I had planned for attaching the rafters to the ridge beam, this was using pryda minigrips on each side of every rafter, skew nailing each rafter and nailing a strap over to the opposite rafter. Use a strongarm (90x45x1800) on the opposite side of each rafter to which each metal rafter bracket was to be attached, nail metal strapping over each existing house rafter. Posts - 3 150x150x3.2m, Cypruss Pine, footings 300x700 using pryda high wind post anchors (150圆00).Īll supporting LVL beams facing the weather will be H3 treated and all LVL will be undercoated and painted.Īfter speaking to the council building engineer he made the following suggestions. Purlins - 70x35, Secured using batten screws Rafters - 22 200x36x2.7m, 9 main rafters each side spaced at 1245 centers House Side Beam - 1 240x36x10m, Continuous span attached to 8 metal rafter brackets Road Side Beam - 1 300x45x10m, Continuous span supported by 3 posts Ridge Beam - 1 525x75x10m, Single span supported by rafters and end supportsįront/Back Beams - 2 300x45x5.5m, Single span between post and house The following is the timber sizes(mm) I have selected to use: The roof will be 2/3 colourbond and 1/3 suntuff solar control. The size of my pergola is 10m x 5.5m x 3.2m, it will be attached to the existing rafters of our 1928 bungalow using steel rafter brackets. All my beam loads were calculated with the software 'designIT' from. This is because of the large structural ridge beam i wanted for my cathedral ceiling look. The timber I have selected to use is Futurebuilds HySpan LVL product. Last week I spoke to a council building engineer about my design so far and he gave me some good feedback and confirmation about fixing methods to be used for the footings, rafter brackets, rafter to ridge connections etc. I have attached a couple of images from Google SketchUp of the new pergola I have designed. I'm in the designing stages of a new pergola to replace my existing one. I live just out of Adelaide in Marleston 5033, I believe its a standard wind rated area.
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