Urgent advice needed: Structural welds on residential steelwork

[spirals413]

The reason for them according to the SE:

 

[tom 748]

plain and simple,go with the plans,do it right

 

[gaz1]

hey spirals seen as your here

im not being noisey here but do you think you have anything to add to the forum now ?

willing to try your hand at mig and arc welding

youve seen our honest comments as much as theres a good bunch of people on here

theres many on here not welding related and we all add our own jobs to the forums as well though its not all welding related

your more than welcome to join in with us all on here

and you might have something to add as well

 

[jimbo84]

Worrying how much "structural" welding like this goes unnoticed and then covered up

It'd be interesting to know how many structures are being held up by nothing more than a bit of tacking between the beams.

 

[Feet 'n Inches]

Worrying how much "structural" welding like this goes unnoticed and then covered up

It'd be interesting to know how many structures are being held up by nothing more than a bit of tacking between the beams.

I was forced to intervene while watching a so-called welder our builder had brought in during the knock-through of the next door bungalow we bought. One beam had to be welded at 90 degrees to the other to support the roof. Even when working on the floor welding angle cleats to the beam, the 'welder' was making a mess - I wasn't about to let him do any positional welding.

 

[colnerov]

Hi, I have to say that I find it odd that the beam is between the columns rather than on top. Why has the architect and structural engineer not decided that it could be easier or safer when they could be dealing with an unknown quantity (the builder) to finish their vision or calculations. After all it doesn't save any space constraints it also removes reliance on the fixing of the two together. I realise that it could be seen as pandering to the lowest common denominator but you have to work with what you've got. Or is there another building type principle at play here?

Colin

 

[roblane65]

I'm glad you seem to have it all in hand now spirals , hope the rest of the build is all plain sailing

 

[tom2207]

Hi, I have to say that I find it odd that the beam is between the columns rather than on top. Why has the architect and structural engineer not decided that it could be easier or safer when they could be dealing with an unknown quantity (the builder) to finish their vision or calculations. After all it doesn't save any space constraints it also removes reliance on the fixing of the two together. I realise that it could be seen as pandering to the lowest common denominator but you have to work with what you've got. Or is there another building type principle at play here?

Colin

joiner . Its put together like its made from wood.

 

[Pete.]

Worrying how much "structural" welding like this goes unnoticed and then covered up

It'd be interesting to know how many structures are being held up by nothing more than a bit of tacking between the beams.

I see *LOADS* of that in demolition. In fact just this morning I was knocking off some 'fully welded' steel support blocks with a hammer. Someone has modified some risers by 'welding' a steel block inside a bottom flange of a RSJ then 'welding' an RSJ on top of the block' to bring it up to floor level. None of it was secure and there were loads done.

 

[mike os]

one other thing.. which may well upset the builder, get the SE and building control to sign off on it before work proceeds, if BC is not happy they can and will make you rectify it before issuing their completion certificate... not having it may make your house more difficult to sell and may invalidate insurance if there are any future issues

 

[Brad93]

I was at the steel works the other week and some of the welding was atrocious, other stuff was world class.

unfortunately a lot of it comes down to cost and time. And when you have a contractor sub out the welding, often they’re gonna want to spend as little as possible.

We were asked to repair the welding on three beams which were for all intents and purposes, tacked in with pigeon poo.

However we had about 18 Hours to do it in poor light, on a dodgy scaffold, in a furnace being sprayed with refractory at the same time. It was probably 4 days work.

We done what we could but needless to say it didn’t get finished

 

[spirals413]

Update: Found a good local mobile welder with 40 years experience who is confident he can fix it. He said it was no problem, he showed me his certifications, pictures of previous jobs, he told me how he would do it and he even showed me what he would use as well as all his other kit in the van (he had absolutely everything). He said he will use 7018. He even asked me to email him the weld spec once I get it. It was obvious he takes a lot of pride in his work, filled me with confidence. Proof is in the pudding but I think it will be fine now thankfully.

The SE will be coming round for a site visit sometime this week too as there are a few other changes to be made at the same time not related to this.

plain and simple,go with the plans,do it right

There's always time to do it right the second time around...(!)

hey spirals seen as your here

im not being noisey here but do you think you have anything to add to the forum now ?

willing to try your hand at mig and arc welding

youve seen our honest comments as much as theres a good bunch of people on here

theres many on here not welding related and we all add our own jobs to the forums as well though its not all welding related

your more than welcome to join in with us all on here

and you might have something to add as well

Thanks Gaz, you guys are great. I'd be happy to contribute to the forum and give back where I can. This isn't my my trade (neither is building work) so I can't promise anything, but I've always been interested in welding. As a hobbyist I've got all the top class cheapo gear ...arc welder and gasless mig . Much prefer arc welding on the odd occassion I do need to weld something. Would love to TIG weld.

Hi, I have to say that I find it odd that the beam is between the columns rather than on top. Why has the architect and structural engineer not decided that it could be easier or safer when they could be dealing with an unknown quantity (the builder) to finish their vision or calculations. After all it doesn't save any space constraints it also removes reliance on the fixing of the two together. I realise that it could be seen as pandering to the lowest common denominator but you have to work with what you've got. Or is there another building type principle at play here?

Colin

Hi Colin, I'm constrained by the overall height of the extension which will be just over 3.2m. Wanted a higher ceiling and no beams showing so the bottom of B11 will be ceiling height and sit on top of C1. The room will be a cinema room and so need somewhere to affix the rear speakers and blackout blinds; can't screw it into the bifolds obviously, so the bifolds are not the full height of the room and there is a bit of wall above them. Also the roof joists will overhang by a metre past B6 with cantilevered joists (not shown on the drawing) which is why B6 is lower and fixed to the side of C1. Also the top and bottom flange needs to be restrained to prevent torsion of the beam which affixing to the side does.

Hope that make sense, it's a bit confusing and not the normal run of the mill job. I guess you could call it a semi self build as there was no architect, I designed it, drew it myself and got it through planning and building control, with a lot of back and forth with the SE to figure out the best way to do things. If the builder just followed the drawings and thought about it before bull dozing ahead then it would have been ok. There is an order to the way things come together.

one other thing.. which may well upset the builder, get the SE and building control to sign off on it before work proceeds, if BC is not happy they can and will make you rectify it before issuing their completion certificate... not having it may make your house more difficult to sell and may invalidate insurance if there are any future issues

Thanks Mike. Well aware of this and will get BC and the SE to sign off on it. They are due a visit soon anyway. I'm still in a position to change things if need be.

I'm glad you seem to have it all in hand now spirals , hope the rest of the build is all plain sailing

Thank you!

 

[mike os]

Glad you are making progress and still, have a positive outlook

 

[KaneH]

One piece of advice with your bi-folds. Make sure the supplier measures the opening after the roof coverings and any finishes have been applied. Also that they leave sufficient room for imposed load deflection on the steelwork when fitting. Not uncommon for suppliers to quote 0 permitted deflection which although is physically impossible give them a supposed get out if things start going wrong. Not sure it would hold up in court if challenged however.

 

[spirals413]

Great piece of advice! Yes, the bi-folds will be the last thing to go in once all the dead loads have been applied. I think I quoted the wrong value in one of my previous posts; the SE calculated deflection is 16.9mm for the ~6m length (L/360).
I've already set the opening height to be ~20mm over the required door height to account for this deflection. In this case imposed/live loads will be insignificant/fairly small since there will be no regular traffic on the roof (it would apply if there was a balcony or if I was building on top of it). Occassional heavy snow loading is the only significant variable live load (worst case: 0.55kN/m2 in my area).

If the supplier measured it wrong and the doors jammed due to not accounting for deflection, then they would no longer be "fit for purpose". I don't think their 0 permitted deflection would hold up in court in this case.

 

[Ton-up]

I thought you'd be lucky to only have 2mm deflection over 6m as you put before!!!

 

[angellonewolf]

would an i beam not been better and give less drop ?

 

[KaneH]

The RHS will have been specified for torsion. I presume there’s are blockwork/brickwork outer leaf going up on the outside of the steel which an I-Section wouldn’t be suitable for unless massively oversized.

 

[spirals413]

I thought you'd be lucky to only have 2mm deflection over 6m as you put before!!!

Yeah, I was reading the deflection limit of the plate welded underneath it, oops

would an i beam not been better and give less drop ?

No. Kane is absolutely correct. The RHS is specified for resistance to torsional effects which is important in this case. There will be brickwork on the outer leaf supported by a welded steel plate causing eccentric loading. An equivalent I beam would have to have a taller web to reduce deflection. A taller web would be more susceptible to torsion, and in turn a larger/wider top and bottom flange would be needed to stabilise the web. By the time you get to an acceptable level of deflection and resistance to torsion, the I beam section would be pretty large and heavy for the span!

 

[spirals413]

Hi guys, been a bit busy with the project, I've been a lot more involved in it than I thought I would be, but I just wanted to stop by and say thanks for everyones help. I'd like to especially acknowledge @Brad93 who messaged me to help out. I would have had no doubt he would have come through and saved the day if I wasn't able to find a welder. Definitely a credit to the forum.
I did find a good local welder however, and he did an excellent job.

Had the SE and BCO come and inspect everything after the corrections were made and it was all passed off thankfully.

As for the builder, unfortunately for him I've been breathing down his neck, and spotted mistake after mistake, until I told him to basically do it properly or get on his bike. After that I think he got the message and got in line and has been taking his time now and doing it properly albeit by consulting me on nearly everything!

I think the most dangerous builders are the ones that think they know everything and reply with "I've been doing it for 20/30 years,so I know what I'm doing". To which I would say, it doesn't mean you've been doing it right for all that time, just that your work has gone unchecked!