dweeb Posted March 28, 2007 Report Share Posted March 28, 2007 Can anyone tell me the maximun span width of 5 by2 timbers.with nothing above only a flat garage roof. i am wanting to take a wall out between my garage and a passage but am not sure if the timbers are using this wall for suport. They go over the wall and into the side of my house Cheers Quote Link to comment Share on other sites More sharing options...
krazykayaker Posted March 28, 2007 Report Share Posted March 28, 2007 dont quote me on this if your garage falls down but: a good rule of thumb for measuring spanning distances of timber is : size of depth of timber x 2 + 1 = max spanning distance in feet eg. 5" timber would be 5 x 2 + 1 = 11 foot max spanning distance hope i haven't confused you!!! and hope it helps Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 28, 2007 Author Report Share Posted March 28, 2007 dont quote me on this if your garage falls down but: a good rule of thumb for measuring spanning distances of timber is : size of depth of timber x 2 + 1 = max spanning distance in feet eg. 5" timber would be 5 x 2 + 1 = 11 foot max spanning distance hope i haven't confused you!!! and hope it helps The distance i need to span is bang on 11ft. so all things being equal and all that, i will get the hammer out Thanks for your help Cheers Quote Link to comment Share on other sites More sharing options...
krazykayaker Posted March 28, 2007 Report Share Posted March 28, 2007 Blimey luks like i've helped someone on PW!!! before you knock it down can u just understand that i take no responsibility for what might happen if i'm wrong go for it it will be fine!! Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 28, 2007 Author Report Share Posted March 28, 2007 What did you say your name and address was No really, thanks for your help Quote Link to comment Share on other sites More sharing options...
krazykayaker Posted March 28, 2007 Report Share Posted March 28, 2007 Quote Link to comment Share on other sites More sharing options...
eagleye Posted March 28, 2007 Report Share Posted March 28, 2007 hi check this site out joist spacing will also affect size and or span http://www.delston.co.uk/joists eagleye Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 28, 2007 Author Report Share Posted March 28, 2007 hi check this site out joist spacing will also affect size and or span http://www.delston.co.uk/joists eagleye Will do thanks Quote Link to comment Share on other sites More sharing options...
njc110381 Posted March 29, 2007 Report Share Posted March 29, 2007 Could you not put a support timber in at 90 degrees to the joists and secure it to the wall at either end? That way, they wouldn't be spanning as far as they are now because they'd be supported in the middle Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 29, 2007 Author Report Share Posted March 29, 2007 Could you not put a support timber in at 90 degrees to the joists and secure it to the wall at either end? That way, they wouldn't be spanning as far as they are now because they'd be supported in the middle Yes i was thinking the very same. Thanks for your help spot on Quote Link to comment Share on other sites More sharing options...
MC Posted March 30, 2007 Report Share Posted March 30, 2007 dont quote me on this if your garage falls down but: a good rule of thumb for measuring spanning distances of timber is : size of depth of timber x 2 + 1 = max spanning distance in feet eg. 5" timber would be 5 x 2 + 1 = 11 foot max spanning distance hope i haven't confused you!!! and hope it helps I believe this works the other way around. You divide your span by 2 and then add 1 11foot span would be, 11 divided by 2 equals 5.5 plus 1 equals 6.5 so to span 11@ you would need 7 x 2. 5 x 2's would do but if you end up with 3 feet of snow one day don't be suprised if you garage roof ends up as your garage floor. Have you not considered pitching it? 5 x 2's would be adequate for a rafter and you gain some storage up in the roof. Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 30, 2007 Author Report Share Posted March 30, 2007 dont quote me on this if your garage falls down but: a good rule of thumb for measuring spanning distances of timber is : size of depth of timber x 2 + 1 = max spanning distance in feet eg. 5" timber would be 5 x 2 + 1 = 11 foot max spanning distance hope i haven't confused you!!! and hope it helps I believe this works the other way around. You divide your span by 2 and then add 1 11foot span would be, 11 divided by 2 equals 5.5 plus 1 equals 6.5 so to span 11@ you would need 7 x 2. 5 x 2's would do but if you end up with 3 feet of snow one day don't be suprised if you garage roof ends up as your garage floor. Have you not considered pitching it? 5 x 2's would be adequate for a rafter and you gain some storage up in the roof. i dont really want to pitch theroof as the flat foof is only around three years old and cost a Bomb to have done. I am going to go down the lines of a lintle i think to give suport where the wall once did. What about sister joists i.e bolting 5/2s along side the ones i have?? Quote Link to comment Share on other sites More sharing options...
MC Posted March 30, 2007 Report Share Posted March 30, 2007 Bolting a secondary joist is probably your best bet, that is how most loft conversions are done. Just make sure that you use dog washers between the timbers so they take the load together. Or you could put a ateel lintol where the wall is/was. Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 30, 2007 Author Report Share Posted March 30, 2007 Bolting a secondary joist is probably your best bet, that is how most loft conversions are done. Just make sure that you use dog washers between the timbers so they take the load together. Or you could put a ateel lintol where the wall is/was. Dog washers? are they like a normal washers with like teeth sticking out either side? If i was to do this do you think i will get away with not using a lintol? Cheers Quote Link to comment Share on other sites More sharing options...
MC Posted March 30, 2007 Report Share Posted March 30, 2007 Dog washers are about 50mm diameter with sharp teeth sticking out both sides, cheap as chips from Screwfix. As long as you have decent support either side then you don't need a lintol. Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 30, 2007 Author Report Share Posted March 30, 2007 Dog washers are about 50mm diameter with sharp teeth sticking out both sides, cheap as chips from Screwfix. As long as you have decent support either side then you don't need a lintol. Which brings me onto another problem After looking at both supports either side i have now discovered that the joists dont go into my house they have has a 90 degree right angle cut in the end and are siting on another lengh of timber which is fixed to the wall what do you think? cheers Quote Link to comment Share on other sites More sharing options...
MC Posted March 30, 2007 Report Share Posted March 30, 2007 I'll have to start charging for Carpentry consultation As long as the support is fixed to the wall well then it will be fine, If you want to be sure then stick a decent rawlbolt through at about 600mm centres. Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 30, 2007 Author Report Share Posted March 30, 2007 I'll have to start charging for Carpentry consultation As long as the support is fixed to the wall well then it will be fine, If you want to be sure then stick a decent rawlbolt through at about 600mm centres. ] Thanks for your help the cheque is in the post cheers Quote Link to comment Share on other sites More sharing options...
eagleye Posted March 30, 2007 Report Share Posted March 30, 2007 getting back to the other suggestions being a builder myself the best way unless you want to get a structral engineer involved is to support the joists with a steel beam where the wall is remove as it is giving a degree of support alternativly you would probably be ok doubling up every other joist and bolting it together using dog washers bolt size M12 coach bolts every metre and as for the timber supporting the joist if you think it needs more fixings try and get them under where the joist bears on the wall plate providing its in the brick not the joint M12 rawlbolts if you need any more advise just ask eagleye Quote Link to comment Share on other sites More sharing options...
dweeb Posted March 30, 2007 Author Report Share Posted March 30, 2007 getting back to the other suggestions being a builder myself the best way unless you want to get a structralengineer involved is to support the joists with a steel beam where the wall is remove as it is giving a degree of support alternativly you would probably be ok doubling up every other joist and bolting it together using dog washers bolt size M12 coach bolts every metre and as for the timber supporting the joist if you think it needs more fixings try and get them under where the joist bears on the wall plate providing its in the brick not the joint M12 rawlbolts if you need any more advise just ask eagleye Thanks for all your help. I plan to make a start sometime next week all being well. Once again thanks dweeb Quote Link to comment Share on other sites More sharing options...
ashcmt Posted April 10, 2007 Report Share Posted April 10, 2007 www.trada.co.uk industry timber regulator - they should have a schedule that will tell you all you need to know on your specific size and grade of timber. Quote Link to comment Share on other sites More sharing options...
tulkyuk Posted April 30, 2007 Report Share Posted April 30, 2007 You Have PM - free help from an Architect (Me B) ) Cheers Paul Quote Link to comment Share on other sites More sharing options...
dweeb Posted May 3, 2007 Author Report Share Posted May 3, 2007 Thanks for the offer mate but i have now put in a lintol to suport the roof. Cheers dweeb Quote Link to comment Share on other sites More sharing options...
al4x Posted May 4, 2007 Report Share Posted May 4, 2007 oooh didn't know PW had resident building experts!! I've a little (well large) issue with a bit of re-roofing we've got to do. We have a section of our house thats not remotely square and currently covered with that err slightly dodgy fibre cement stuff The base is currently about 11.5m x 6.5m and the roof has three roof trusses supporting 5 purlins then the roof is entirely covered with 3/4 inch tongued and groove boarding and then the cement sheets. All the roof timbers are 50x175 diameter. We have a roofer quite happy to re-cover by laying rafters on top of the boards and using a lightweight redland Cambrian tile on top. How do I work out whether the existing roof structure need to be beefed up. Is it best left to a structural engineer, as at the moment we have sadly employed probably the worst architect on the planet and I'd not trust any solution he came up with now. Quote Link to comment Share on other sites More sharing options...
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