Does anyone know a Balustrade supplier with this type of fixing?

[Mikey]

Looking to attach a glass balustrade to a timber frame for a balcony and Juliette balcony. I’m told this type of fixing (see photos attached) is what we need, but I can’t find a supplier anywhere!

[Mr Punter]

I have not seen anything as small as those.  S3i do a large range and may be able to point you in the right direction.

[JohnMo]

Made2Measure.co.uk do them

[Alan Ambrose]

Often called 'pig-nosed' bolts.

[Haylingbilly]

I got mine from bare metals - www.bearmetals.co.uk

 

[Mikey]

Thanks everyone, I will check out those suggestions.  

 

Love this forum!!!

 

[bassanclan]

F Brundle nr Ilkeston

[Conor]

Building control will most likely want to see a piece of paper showing that the ballustrade meets the loading requirements... So you might need to get the glass supplier to include these fixings as supply it as a "system" and confirm it meets the requirements.

[JohnMo]

29 minutes ago, Conor said:

Building control will most likely want to see a piece of paper showing that the ballustrade meets the loading requirements... So you might need to get the glass supplier to include these fixings as supply it as a "system" and confirm it meets the requirements.

Mine did, made2measure have them on their site for downloading. But the structural engineer stated what the wind and impact loading were. But calcs are for the whole systems they sell. I needed the purchase receipt and the supporting calcs for building control.

[Glen]

These look very similar to fixings we use at work for installing glass & perspex signs. A company called www.Ukpos.com supply them. 

[Gus Potter]

This is minefield!

 

Generally the folk that supply the glass and track test it on a rig that is very stiff. When you look at the fine print of their test data they tell you this... but they don't take any responsibility for the fixings of the glass or glass mounting track to the supporting structure.

 

Your general SE designs the principle structure but when you look at their fine print it often says "glass / track and fixings to be designed by specialists. So no one checks the actual fixing between the track and the main structure. The main reason for this is that the supporting structure can be wood/ concrete / steel etc.. everyone passes the buck... and for good reason as it takes time to do the calcs as every job is different. In Scotland everyone knows that the fixings must be checked and then you should produce a drawing which takes time too.. but in England (apart from Yorkshire folk who are in my experience very shrewed and clever) you are still often in the dark ages I have to say! It's ok I'm not a scot nat.. just yanking your chain... but if you followed the process below (and paid for that part of the design) you would not get into trouble.

 

Below is a part of one of my designs for a glass balustrade that checks a side mounted track and fixings into a structural steel assembly.

 

 

 

What I'm doing here is the bit that the general SE doesn't want to do or the glass and track supplier as both take time, effort and an understanding of the behaviour of what it is they are fixing the glass and track to.

 

The funny looking equation is just a mixed up version of O level maths (quadratic equation) that you would have been taught at 15 years old..  if maybe been born before 2000.. it's nothing geeky.

 

Most of the calculation above determines the tension and vertical load on the fixing between the track and what is supporting the glass. The tension in the bolt varies from track type to type and depending on what type of material the track bears against and what material the fixing go into. But make no mistake.. the material you are fixing into can have a dramatic impact on the bolt forces and the possibility that the whole thing comes lose.

 

The above is for a fixing into a steel backing plate (the hatch suggests concrete but it is actually steel) but if fixing to timber the red bearing area would extend upwards and the forces in the bolts would increase a lot. The main thing is that a few mm in terms of bolt postition or a change in material can have a dramatic effect.

 

That is why no one wants to step up to the plate!

 

In summary the fixings are the key bit and what they are going into. Failure to check all the different parts will lead to disappointment not least. For all on BH .. if you are doing this type of balustrade then it is essential to follow the instructions.. don't make it up as you go along!

 

@Mikey hope this helps a bit.

 

 

 

 

 

Edited November 16, 2023 by Gus Potter

[trialuser]

A question for anyone but hopefully @Gus Potter will chip in as I'm in Scotland.

Does all this malarkey also apply to non glass balustrades and fabricated steel stairs.

I'm building a large extension in Dumfries and Galloway and was going to self fabricate a heavy box section steel stairs with wooden treads. or if I had any doubts about my welding I would get a local steel fabricator to build them. I wasnt going to get to involved with structural calcs, just over engineer.

Something along these lines (pic pinched from internet)

Thanks

[markc]

If you are wanting or needing someone to sign off on something then calcs are needed (or proof load tests). Likewise if you are pushing the boundaries of material compressive and tensile strengths then calcs are a must. Overengineering a small simple structure like a stair is much easier and straightforward, if it looks and feels right then it usually is. 

[Dan F]

@Mikey Our builders used https://www.originarchitectural.co.uk/.  They supply also sorts of fittings and also did the calc for him I think..

[Alan Ambrose]

>>> Below is a part of one of my designs for a glass balustrade

 

Hi Gus, just to understand - are you saying 'the profile manufacturer has done the calcs on the profile, we just need to ensure the bolts don't fail before the profile does'?

 

Presumably there are there some standard stair loadings that you are using e.g. the 0.57 shear load?

 

Is there some rule of thumb on what is required to be SE calculated and what isn't? ... In principle you could calc the loading for every fastening used in a build, but I guess we don't have the time and energy for that?

[Gus Potter]

On 02/12/2023 at 09:41, trialuser said:

A question for anyone but hopefully @Gus Potter will chip in as I'm in Scotland.

Does all this malarkey also apply to non glass balustrades and fabricated steel stairs.

Yes it can at times, explanation follows. No point in having a fabricated stair if the connections are not considered.

On 02/12/2023 at 14:43, Alan Ambrose said:

Hi Gus, just to understand - are you saying 'the profile manufacturer has done the calcs on the profile, we just need to ensure the bolts don't fail before the profile does'?

 

Presumably there are there some standard stair loadings that you are using e.g. the 0.57 shear load?

 

Is there some rule of thumb on what is required to be SE calculated and what isn't? ... In principle you could calc the loading for every fastening used in a build, but I guess we don't have the time and energy for that?

Hello all.

 

A quick bit about glass ballustrades, off the shelf steel ones and stair cases.

 

These types of barriers / stairs are designed to resist the prescribed loads in BS 6399 part one and BS 6180 for example. These codes allow for a horizontal load to the top of the hand rail and the infill bit below, could be glass or spindals. There is also a limit on the amount the handrail at the top can deflect horizontally.. serviceability.. so it doesn't "feel insecure".

 

Now in particular the glass balustrade manufacture's need to be competetive so they test (and make public their results) their product on a very stiff and strong test rig that doesn't bend much (twist) at all. This way they get the best performance out of their product, fair enough to them, it's a commercial world. When they use a stiff test rig the distance between the bolt centre and the centre of the effective bearing ( the bit at the track edge) is at it's maximum thus the bolt tension is at it's minimum.

 

If you're fixing your balustrade track to say a well prepared thick concrete slab then this could come close to the stiffness of the test rig. But if fixing to something else, say timber or there is roofing membrane between the track and underlying material then this changes (increases) the forces in the bolt and at the track edge, quite a lot at times as it shortens the effective distance between the bearing surface at the edge of the track and the bolt.

 

What the calculations I posted do is to basically take the horizontal loadings on the balustrade and multiply them by the height at which they act. This gives the bending moment, a rotational force in this case, just like a wheel nut spanner. This rotational force is then worked back the other way to give the tensile force in the bolt. But the tensile force will be different, and the difference can be quite a lot, depending on what you are fixing to. The tensile force in the bolt has to be counteracted by the edge forces on the track. Because the distance between the edge of the track and bolt is small the horizontal forces on the balustrade fixings are very much amplified.

 

If you are fixing into timber or something that is softer than the test bed the timber / something can easily crush near the edge of the track, so you need more timber say which shortens the effective distance between the bolt and counteracting force at the edge of the track. The forces in the bolt are now much more so you need to check the bolt and what you are fixing into to avoid crushing of what you are fixing to at the edge of the track. The calculations are repeated (iterative)  until you find the balancing point where the tension force in the bolt is equal to the material pushing back the other way at the track edge.

 

@Alan Ambrose Good spot the shear loading. As this is a side fixed track the vertical shear load comes from the self weight of the balustrade thus I check the bolt for combined tension and shear. This is particularly important if using resin anchors.

 

Now the above may sound like a maths excercise but actually it can avoid disappointment.

 

One example. You fix a typical slender aluminium balustrade track to the timber edge beam of say a stair or balcony. You have a party and a few folk lean against it. In the morning you go out to clean up and find the balustrade feels a bit loose. All it takes is for the timber to crush a little at the very edge of the track and now it feels slack. If you can't access the bolts to give them a tighten up then you often just have to live with it. Best to design it right in the first place.

 

In fairness to the manufacture's they don't know what you are fixing to, the designer of the main structure often does not know what kind of track / balustrade you'll go for at the end of the day so there is this design gap, no man's land where one key part is often not explicitly checked and often overlooked. In Scotland we insist that all parts are checked to ensure everything is safe and serviceable, hence the calculations posted. This also includes fabricate strairs to ensure the loads on the stair are transferred safely to the main structure.

 

 

 

 

 

 

Edited December 4, 2023 by Gus Potter

[trialuser]

Thanks

[Alan Ambrose]

>> so you need more timber say which shortens the effective distance between the bolt and counteracting force at the edge of the track

 

Ooh, very subtle.

 

>>> may sound like a maths exercise but actually it can avoid disappointment

 

Sounds like a great SE tag line

 

Any SE-101 books you can recommend?