saveasteading Posted February 28 Share Posted February 28 2 minutes ago, Thorfun said: anyone have a calculation as to the pull out resistance As I've said several times, as have others, the pullout isn't a problem but the rotation and aluminium hardness might be. I'm not saying it again and will drop out of the conversation. 3 Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 19 minutes ago, saveasteading said: As I've said several times, as have others, the pullout isn't a problem but the rotation and aluminium hardness might be. I'm not saying it again and will drop out of the conversation. oh. sorry for my misunderstanding of the issue here and it's a shame you won't contribute further. i'm now interested in how the threaded bar would differ in rotation and aluminium hardness compared to the coach screws? Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 In the past I have actually screwed threaded rod into wood effectively but feel proper designed long screws have been designed for that specifically. 1 Link to comment Share on other sites More sharing options...
Russell griffiths Posted February 28 Share Posted February 28 1 Link to comment Share on other sites More sharing options...
Russell griffiths Posted February 28 Share Posted February 28 Look that up, Link to comment Share on other sites More sharing options...
Alan Ambrose Posted February 28 Share Posted February 28 Are you sure your BC won't require SE calcs anyway? BTW this is the thread and post I was thinking about, you'll see Gus has highlighted the zone that will likely fail first - (different style of fixing, but similar problem): Also a few posts down, Gus says "These types of barriers / stairs are designed to resist the prescribed loads in BS 6399 part one and BS 6180 for example". So, there's your loading requirement. 1 Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 I picked up on Gus,s point re fixing to timber. “so you need more timber say which shortens the effective distance between the bolt and counteracting force at the edge of the track” this will be the hardwood flooring which extends either side of the ally track and much harder (less crushing) that the glulam (softwood). Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 31 minutes ago, joe90 said: I picked up on Gus,s point re fixing to timber. “so you need more timber say which shortens the effective distance between the bolt and counteracting force at the edge of the track” this will be the hardwood flooring which extends either side of the ally track and much harder (less crushing) that the glulam (softwood). but the finished flooring is like a 3mm layer of hardwood. the rest is softwood ply. i wonder if i could, as was previously suggested, change the underlay under the channel to 5mm ply. Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 45 minutes ago, Alan Ambrose said: Are you sure your BC won't require SE calcs anyway? not sure. i will cross that bridge if/when i get to it. one thing on my side is that one of the sections is an L-shape so will have the other 'leg' to assist in resistance. Link to comment Share on other sites More sharing options...
markc Posted February 28 Share Posted February 28 @Thorfun what is the length of run? Turning a corner makes life much easier. With balustrades it’s not just the ultimate strength but also the deflection under load (flex when it’s rocked back and forth) the fixings may well be massively over the top to resist load but floor flex or compression can give unacceptable deflection at the top. This is why you often see vertical glass strips either in front or behind to act as buttresses to reduce movement. Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 10 minutes ago, markc said: @Thorfun what is the length of run? Turning a corner makes life much easier. With balustrades it’s not just the ultimate strength but also the deflection under load (flex when it’s rocked back and forth) the fixings may well be massively over the top to resist load but floor flex or compression can give unacceptable deflection at the top. This is why you often see vertical glass strips either in front or behind to act as buttresses to reduce movement. measurements added Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 39 minutes ago, Thorfun said: wonder if i could, as was previously suggested, change the underlay under the channel to 5mm ply. Or belt and braces 5mm steel or ally 41 minutes ago, Thorfun said: but the finished flooring is like a 3mm layer of hardwood. the rest is softwood ply. But the crushing effect is on the hardwood layer spread over a greater area by the ply underneath. 2 Link to comment Share on other sites More sharing options...
markc Posted February 28 Share Posted February 28 The L shape is pretty much self supporting (if you join at the corner. And the nearest run, I’m guessing is between walls? So a support/restraint near the top at both ends removes the cantilever load from the bottom. 2 Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 36 minutes ago, markc said: The L shape is pretty much self supporting (if you join at the corner. And the nearest run, I’m guessing is between walls? So a support/restraint near the top at both ends removes the cantilever load from the bottom. so, there's no timber up the wall on the nearest run to attach anything to. i could use some heavy duty plasterboard fixings to assist with a glass bracket holding the glass but that would only really help with wobble i guess. i'm aware i can cut out the plasterboard and put timbers but would rather not go through that disruption to the decoration if at all possible. the balustrade is designed to not have the side support afaik. Link to comment Share on other sites More sharing options...
Alan Ambrose Posted February 28 Share Posted February 28 Well if you can somehow subtly determine beforehand, and he/she says yes, then you'll end up paying for the SE anyway. It does all sound a bit formal... https://www.cross-safety.org/sites/default/files/2019-12/structural-safety-glass-balustrades.pdf BTW here are the loads from BS 6399 - they don't seem too onerous, there's some additional detail on fixing etc in :6180 ... 1 Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 If I may, to put this thread in context the balustrade is supplied “fit for purpose” and so must have been tested to be able to sell it on the market. I agree with additional washers under bolts/screws (because I am OCD) The only issue is fixing it to timber and mitigating any “rocking”. I believe the consensus here is long (150mm +) screws will suffice the pull out requirement. The decision to be made by @Thorfun is how to stop possible rocking on the 5mm underlay which could be by replacing the foam around fixings with 5mm solid material. (I would go 100mm wide) I am still of the opinion that the 14mm hardwood topped flooring will spread the rotational force by much more than the width of the ally profile making it stable. As we have read many times BCO,s are not consistent ( luckily mine was very pragmatic) and if after fitting/sign off they insist on calcs/testing then do it retrospectively otherwise it will never get fitted 🤷♂️ 2 Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 (edited) 28 minutes ago, joe90 said: If I may, to put this thread in context the balustrade is supplied “fit for purpose” and so must have been tested to be able to sell it on the market. I agree with additional washers under bolts/screws (because I am OCD) The only issue is fixing it to timber and mitigating any “rocking”. I believe the consensus here is long (150mm +) screws will suffice the pull out requirement. The decision to be made by @Thorfun is how to stop possible rocking on the 5mm underlay which could be by replacing the foam around fixings with 5mm solid material. (I would go 100mm wide) I am still of the opinion that the 14mm hardwood topped flooring will spread the rotational force by much more than the width of the ally profile making it stable. As we have read many times BCO,s are not consistent ( luckily mine was very pragmatic) and if after fitting/sign off they insist on calcs/testing then do it retrospectively otherwise it will never get fitted 🤷♂️ wonderful summary and spot on, thank you. M12 x 160mm coach screws is set in stone (or timber i guess would be more accurate! 🤣) the decision about whether to cut out the finished floor, use some form of steel pipe spacer, or replace the underlay with a solid material is still in discussion with SWMBO. i'm leaning towards cutting the finished floor out and fixing directly to the 22m chipboard flooring and then simply caulking any gap between the channel and the floor but i'm still mulling it over. i will also consider a couple of brackets at the top of the straight run for a little additional support against wobbling. thank you so much to everyone's thoughts and assistance so far. it is, as always, invaluable and i may not always use the suggestions but i do appreciate the differing opinions and solutions to a problem. Edited February 28 by Thorfun 2 Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 10 minutes ago, Thorfun said: the decision about whether to cut out the finished floor, I suppose the issue may be how you finish the bit of floor on the outside of the ally and vertical surface of the glulam? I think caulking the flooring to the ally will look messy and cleaner leaving it where it is. Go overboard and get 100mm x100mm 5 mm steel plates cut and inserted under the fixings after cutting out the foam underlay 🤷♂️it’s all peace of mind with what you decide 😎 1 Link to comment Share on other sites More sharing options...
Thorfun Posted February 28 Author Share Posted February 28 1 minute ago, joe90 said: I think caulking the flooring to the ally will look messy and cleaner leaving it where it is. this is also what the wife is thinking. Link to comment Share on other sites More sharing options...
joe90 Posted February 28 Share Posted February 28 4 minutes ago, Thorfun said: this is also what the wife is thinking. Great minds think alike 🤣 1 Link to comment Share on other sites More sharing options...
Gus Potter Posted March 8 Share Posted March 8 On 27/02/2024 at 18:14, Thorfun said: Not seen @Gus Potteron here for a while. Would be great to get his input. Don’t suppose you have a link to that previous thread do you? Bit of an IT disaster at this end as I keep loosing what I have written and folk I have quoted. @Thorfun thank you for the kind words. On 27/02/2024 at 18:43, saveasteading said: @Gus Potter sometimes looks at my input so I'll @ him too, but he is probably busy doing paid work. Yes busy with the day job here, also my Mum is 92 and has just bought a house close to me so trying to get that in order.. Have to say though BH is great, love learning from others and seeing new folk coming on board with new ideas.. younger folk willing to learn, older / experienced folk passing on knowledge and adapting what they do know to the lastest ideas from new members etc, also older folk revisiting what we thought was ok in the past but maybe less so today as materials, fixings and analysies techniques evolve etc. There are good few professionals on BH that do this sort of thing as a day job like myself... Contractors, Designers and folk that have other technical background.. I appreciate their knowledge and will be the first to say.. thank you all.. as I have learnt a lot from you all. @Thorfun Have had a look back but can't find it just at the moment. I've tried to google it but that post is not coming up. From memory it was basically showing how the forces in ballustrade fixings can be pretty high! I've had a quick look through the thread. Lots of good technical comment from you all which I appreciate, it makes me think also! Earlier today I turned down a job for designing and doing the steel detailing for some extra stairs and landings for the Glasgow Hydro Arena (~15k seat capacity) as I don't have time to do it. The main thing that stopped me from doing it was the time you need to spend coordinating all the fixings and checking that everyone else involved in the process knows what they are doing, they often do within their field.. but have no clue about how the design works holistically and if it can be built safely and in a cost effective way.. Here it gets dangerous in terms of safety, that also means you in a domestic setting. It is also a big business risk for me as there is mention of collateral warranties. This means I can do say 10k of design work and steel detailing but expose my insurer / myself to a disproportionate claim.. excuse the spelling. It's not that I'm being difficult.. I'm just doing what I was trained to do..initially as a Civil Engineer.. which means I have a social responsibility to society. I mention this above as in the thread folk seem to think you can swap one fixing for another or change the principle of the design even if they are of the same diameter and length the ductility of the fixing may be different and thus could behave in a diferent way. I think there was a suggestion of fixing through the flooring.. but the flooring needs to be able to move about a bit.. so you no longer comply with the flooring manufacture's spec..let it move about.. no point in complaining later that gaps have appeared in your expensive flooring if you have clamped it at one end so you can get your ballustrade fixings to work. I think there was mention of fixing into the tops of posi joists etc. But if you are introducing significant forces (particularly bending forces) into these then you void the posi joist warranty as I'll guarentee you'll compromise the web etc connections..not least in terms of your nail / bottom track fixings but also nail their plate teeth connection and edge and end spacing. If you don't believe me phone up the manufacturer! Now I may seem like I'm ranting a bit but just say a BC officer asks the same question? For me.. I can see that lots of folk are face with the reality of the self built / renovation market. Fundamentally there is a lack of designers that are avialable to guide say folk on BH. At my end I win work by saying to Clients.. yes I may be on the face of it be a bit more expensive.. but I bring a lot more to the table.. One thing I do do is to sit down with my Clients and find out what they know.. I'm often surprised just how much they do know but just need someone to put a bit of structure to it all and give them a bit of a confidence boost! In terms of the OP. Go back to basics and try and simplify the problem. Fix the primary structure to primary structure and make sure the primary structure won't twist. If it does you'll end up with a bendy handrail etc. @Thorfun I've not look that closely at your detail as had a horrible day trying to sort out a parapet detail.. will try a bit later to see if I have any suggestions that you can chew over. Link to comment Share on other sites More sharing options...
Gus Potter Posted March 8 Share Posted March 8 On 26/02/2024 at 17:40, Thorfun said: Additional information: Give me a call on the phone or PM me. You find my phone number on the internet, text me first so I know it's you as I'm a bit deaf as in deaf as a post. Happy to spend 10 min having a chat. Any spammers.. every day is a school day.. Link to comment Share on other sites More sharing options...
Thorfun Posted March 9 Author Share Posted March 9 18 hours ago, Gus Potter said: Give me a call on the phone or PM me. You find my phone number on the internet, text me first so I know it's you as I'm a bit deaf as in deaf as a post. Happy to spend 10 min having a chat. Any spammers.. every day is a school day.. 18 hours ago, Gus Potter said: Bit of an IT disaster at this end as I keep loosing what I have written and folk I have quoted. @Thorfun thank you for the kind words. Yes busy with the day job here, also my Mum is 92 and has just bought a house close to me so trying to get that in order.. Have to say though BH is great, love learning from others and seeing new folk coming on board with new ideas.. younger folk willing to learn, older / experienced folk passing on knowledge and adapting what they do know to the lastest ideas from new members etc, also older folk revisiting what we thought was ok in the past but maybe less so today as materials, fixings and analysies techniques evolve etc. There are good few professionals on BH that do this sort of thing as a day job like myself... Contractors, Designers and folk that have other technical background.. I appreciate their knowledge and will be the first to say.. thank you all.. as I have learnt a lot from you all. @Thorfun Have had a look back but can't find it just at the moment. I've tried to google it but that post is not coming up. From memory it was basically showing how the forces in ballustrade fixings can be pretty high! I've had a quick look through the thread. Lots of good technical comment from you all which I appreciate, it makes me think also! Earlier today I turned down a job for designing and doing the steel detailing for some extra stairs and landings for the Glasgow Hydro Arena (~15k seat capacity) as I don't have time to do it. The main thing that stopped me from doing it was the time you need to spend coordinating all the fixings and checking that everyone else involved in the process knows what they are doing, they often do within their field.. but have no clue about how the design works holistically and if it can be built safely and in a cost effective way.. Here it gets dangerous in terms of safety, that also means you in a domestic setting. It is also a big business risk for me as there is mention of collateral warranties. This means I can do say 10k of design work and steel detailing but expose my insurer / myself to a disproportionate claim.. excuse the spelling. It's not that I'm being difficult.. I'm just doing what I was trained to do..initially as a Civil Engineer.. which means I have a social responsibility to society. I mention this above as in the thread folk seem to think you can swap one fixing for another or change the principle of the design even if they are of the same diameter and length the ductility of the fixing may be different and thus could behave in a diferent way. I think there was a suggestion of fixing through the flooring.. but the flooring needs to be able to move about a bit.. so you no longer comply with the flooring manufacture's spec..let it move about.. no point in complaining later that gaps have appeared in your expensive flooring if you have clamped it at one end so you can get your ballustrade fixings to work. I think there was mention of fixing into the tops of posi joists etc. But if you are introducing significant forces (particularly bending forces) into these then you void the posi joist warranty as I'll guarentee you'll compromise the web etc connections..not least in terms of your nail / bottom track fixings but also nail their plate teeth connection and edge and end spacing. If you don't believe me phone up the manufacturer! Now I may seem like I'm ranting a bit but just say a BC officer asks the same question? For me.. I can see that lots of folk are face with the reality of the self built / renovation market. Fundamentally there is a lack of designers that are avialable to guide say folk on BH. At my end I win work by saying to Clients.. yes I may be on the face of it be a bit more expensive.. but I bring a lot more to the table.. One thing I do do is to sit down with my Clients and find out what they know.. I'm often surprised just how much they do know but just need someone to put a bit of structure to it all and give them a bit of a confidence boost! In terms of the OP. Go back to basics and try and simplify the problem. Fix the primary structure to primary structure and make sure the primary structure won't twist. If it does you'll end up with a bendy handrail etc. @Thorfun I've not look that closely at your detail as had a horrible day trying to sort out a parapet detail.. will try a bit later to see if I have any suggestions that you can chew over. Hi Gus. thanks for the response. I completely understand about the reluctance to design a system for a stranger on the internet and am fully aware of the implications with insurance etc. not was I was asking either! I'm very happy with your response and you have basically confirmed what a couple of other professionals that I know and I have managed to persuade the wife that we need to cut out the floating floor and fix down directly to the structure. which is what we've been doing today. I'm very happy with how it's going and I'm confident that BCO will be too! thanks for the offer of the phone call but I don't think that will be necessary. thanks again for the response, have a great weekend and good luck with the paid work! 🙂 Link to comment Share on other sites More sharing options...
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