Browse Forums General Discussion 1 Feb 20, 2007 1:58 pm We're thinking about putting a new roof on our house. The current roof is asbestos, which has been covered with metal tiles (UGLY!!!). The architect who did some preliminary plans for us tells me we need to incorporate more tie downs in order to up the wind rating (???) of the house.
Can anyone here elaborate on that point for me? Is it hard to install tiedowns without ripping walls off? Cheers for the advice! Lotte Re: New roof - Tie Downs?!!! 2Feb 20, 2007 4:47 pm Lotte, the type & extent of roof ties to an extent are dependant on the wind classification for your particular site.
In brief, this is determined from the 'Region' you are in. The 'Terrain Catagory', 'Topographic Classification' & the 'Shielding Classification. This scenario happens usually when people replace a heavy weight roof product with a lighter one such as corrugated steel which has greater uplift & requires increased tie down. It can also be required when reroofing, to bring the tie down up to current standards The worst case will be if tie downs need to go to the subfloor structure & then you may have to remove plaster. Peter Clarkson - AusDesign Australia www.ausdesign.com.au This information is intended to provide general information only. It does not purport to be a comprehensive advice. Re: New roof - Tie Downs?!!! 4Feb 22, 2007 8:37 am It's within the scope of a competent DIYer.
The tie down is to stop the roof blowing off. In a lower wind catagory in say a suburban built up area it may only mean you require hoop iron straps over the roof battens & nailed to the rafters. In a higher wind area you may need to also strap the rafters to the top plate & / or the wall studs. In a higher again you may need to also tie the top plate to the subfloor [ or slab ] - usually with a metal rod down through the wall frame. Within Aus there are 4 regions - Region A [ normal] most inland & southern areas. Region B [ intermediate ] a narrow strip inland running around the top of Aus from near Coffs Harbour to Geraldton. Region C [ tropical cyclone ] narrow coastal strip around from Broome.to Bundaberg. Region D [ severe cyclone ] around Pt. Hedland area W.A. The Brisbane area is Region B. Within the regions are the differing catagories as mentioned previously. So for example a house in a valley shielded by other homes would require less than a home half way up the hill exposed to the wind. A home in Brisbane situated the same as an identical home in Melb. would require more tie down. Peter Clarkson - AusDesign Australia www.ausdesign.com.au This information is intended to provide general information only. It does not purport to be a comprehensive advice. Thank you Pulse, I thought we did the right things; external shutters on all windows down all day, west side of the house nearly completely in the shadow of the large two… 6 25117 2 7937 This certainly doesn't look good. I would be engaging with an independent inspector to have a look at this. As for the unscheduled site visits, most builders are quite… 1 21994 |