Steel Beam question

[f114306]

Hello everyone, not strictly a workshop build but a build nonetheless.

In my Structural Engineers builders details that specify a steel beam over a bifold door opening, it shows a ‘split block course to suit’ on top of the steel beam and a 100 x 50 C16 wall plate on top of that.

I’m curious about the ‘split block course to suit’ and why I might need it if indeed I need it at all. I’m not a builder by any stretch but I’m learning all the time, so any insight appreciated.

CG

 

[SLM]

In my experience, structural engineers can be massively over cautious; as another engineer, with no skin in the game, and they’ll tell you a lighter solution will work.

However, the reason for this is likely professional liability!

So, I can’t answer your question, but would advise caution and to be absolutely certain of any deviation from the engineer’s spec; if you experience problems in the future, it is down to the engineer, if you have followed their spec.

 

[Jacob]

Hello everyone, not strictly a workshop build but a build nonetheless.

In my Structural Engineers builders details that specify a steel beam over a bifold door opening, it shows a ‘split block course to suit’ on top of the steel beam and a 100 x 50 C16 wall plate on top of that.

I’m curious about the ‘split block course to suit’ and why I might need it if indeed I need it at all. I’m not a builder by any stretch but I’m learning all the time, so any insight appreciated.

CG

Just googled ‘split block course' and apparently it's cosmetic - having the appearance of split blocks but actually a cast beam, or covering a steel beam. News to me!
In other words you don't need it if you don't want it
It accounts for those wide openings in some modern stone faced buildings with very little obviously spanning the gap structurally.
OTOH I'm not an engineer so could be quite wrong.

 

[Sideways]

"to suit" sounds like a get out of jail free comment. It's unspecified by the engineer and left to your discretion so it can't be structurally important.

 

[SLM]

Is it specified on the upper flange, or as infill, sitting on the lower flange, in front of the web?

 

[Adam W.]

Just regard it as a type of boxing in and sleep easy.

Make sure you isolate the steel from the mortar, as it will eventually bleed through otherwise.

 

[Phil Pascoe]

In my experience, structural engineers can be massively over cautious; as another engineer, with no skin in the game, and they’ll tell you a lighter solution will work.

Did you mean "ask" another... ?

 

[SLM]

Did you mean "ask" another... ?

Deed I dad, Phil

 

[peterw3035]

I think the split course he is referring to is simply to raise the wall above the steel so that the wall plate lines through. It doesn't need to be blockwork you could simply pack under the 100x50 plate with timber 100mm wide by the required thickness so that the top lines through.

 

[ChaiLatte]

I’m curious about the ‘split block course to suit’

An alternative name might be 'cut block' or 'slip block'.

For some reason, cuts are generally vertical and splits are generally horizontal.

It is a block that is smaller in height than a full one, used to make up the difference between the steel beam and the adjacent full height block courses. The 'to suit' is because its dimension will depend on the exact height of the steel beam and where the beam's underside ends up in relation to a block course joint.

In the end, you need a wall that is the same level all the way along it, so the underside of the timber wall plate can sit on it.

It is possible to buy them ready made.

https://www.thomasarmstrongconcreteblocks.co.uk/slip-blocks.html

 

[SLM]

An alternative name might be 'cut block' or 'slip block'.

For some reason, cuts are generally vertical and splits are generally horizontal.

It is a block that is smaller in height than a full one, used to make up the difference between the steel beam and the adjacent full height block courses. The 'to suit' is because its dimension will depend on the exact height of the steel beam and where the beam's underside ends up in relation to a block course joint.

In the end, you need a wall that is the same level all the way along it, so the underside of the timber wall plate can sit on it.

It is possible to buy them ready made.

https://www.thomasarmstrongconcreteblocks.co.uk/slip-blocks.html

An authoritative answer!

 

[f114306]

An authoritative answer indeed.

Thanks to everyone who responded I’m now clear on the meaning and purpose.

However, @Adam W. mentioned isolating the steel from the mortar. Clips that I’ve watched online, dangerous I know, just show mortar being slapped straight on top of steel. What do you use to do the isolation?

CG

 

[MikeJhn]

FWIW I am a Retired Structural Engineer, post 10 is correct as you say, the steel beam should be red oxide painted to prevent bleed through, if bought from a reputable steel fabricator this would be done as a matter of course.

 

[SLM]

Exactly as Mike says. When I’ve bought steel in the past, there’s always been the option of having it painted, or doing so yourself.

 

[Adam W.]

Use anything which keeps it from contacting mortar and plaster. DPM, visqueen, duct tape, etc, or you can paint it if you want, but don't forget paint scratches off and may not be the best option.

 

[pauljhaigh58]

Hi the split course is the one where it’ says blockwork internal leaf .the block is just cut to size by the bricklayer hope thi helps
Paul

 

[MikeJhn]

DPM, Visqueen or duct tape will hold moisture (condensation) against the steel and eventually cause rusting and failure, do not use any kind of loose wrap.

 

[Dave Moore]

Hello everyone, not strictly a workshop build but a build nonetheless.

In my Structural Engineers builders details that specify a steel beam over a bifold door opening, it shows a ‘split block course to suit’ on top of the steel beam and a 100 x 50 C16 wall plate on top of that.

I’m curious about the ‘split block course to suit’ and why I might need it if indeed I need it at all. I’m not a builder by any stretch but I’m learning all the time, so any insight appreciated.

CG

You should get calculations for the beam design supplied as it comes under CE regulations and you should also get all certs for the steel plus a CE certificate from the fabricator. This is law.
Regards,
Dave

 

[Adam W.]

DPM, Visqueen or duct tape will hold moisture (condensation) against the steel and eventually cause rusting and failure, do not use any kind of loose wrap.

On the interior wall/leaf of a centrally heated building, sure thing.

 

[MikeJhn]

Cooking and even breathing create moisture.