Steel instead of glued laminated timber for supporting the intermediate floor

[TuXy]

VKR is often used for columns. But it works just as well to use as a beam.

I have read about this and it could indeed be interesting for that argument of not having to splice the roof trusses.

Do you have any idea about dimensions?

 

[StrukturalAB]

I have read about this and it can be interesting for the very reason of not needing to splice rafters.

Do you have information on dimensions?

Not for your project. But if you compare I (m^4), which is the moment of inertia for the steel beams you have in mind, and a VKR or KKR (pretty much the same thing), they should be the same. HEA and HEB are optimized for load in one direction, while VKR is for load in two (like columns, etc.). So there will be a bit more steel with a VKR.

 

[TuXy]

Not for your project. But if you compare l (m^4), which is the moment of inertia for the steel beams you're considering, with a VKR or KKR (basically the same), they should be equal. HEA and HEB are optimized for load in one direction, while VKR is for load in two (like columns, etc.). So there's a bit more steel with a VKR.

When I compare an HEA 180 with a VKR 180x180x8.0 it gives 25.10 vs 26.61 where Wx gives 294 vs 296.

I interpret that as an HEA 180 can be replaced by a VKR 180x180x8.0

Am I thinking correctly?

Do you have any input regarding ears on the beam? I've seen that concept before.

 

[Plupp 405730]

Why would one want to use a VKR beam instead of HEA?

 

[StrukturalAB]

Why would one want to insert a VKR beam instead of HEA?

To avoid support on the bottom flange, which makes it complicated to fit the beam.

 

[Plupp 405730]

To avoid a buildup on the underside flange, which makes it complicated to install the beam.

Aha, you want to cut a straight notch in the joists so you can install the beam, this places quite high demands on the ears that need to be well-designed.

 

[StrukturalAB]

Comparing an HEA 180 with a VKR 180x180x8.0 gives 25.10 vs 26.61 where Wx gives 294 vs 296.

I interpret that as an HEA 180 can be replaced by a VKR 180x180x8.0

Am I thinking correctly?

Do you have any input regarding ears on the beam? I've seen that concept before.

Correct thinking regarding the moment of inertia.

Ears might have been the wrong term. It should be something that looks like a joist hanger, on which the beam rests for vertical load. But the sides can be longer so you screw a bit into the beam. Compare the solution with the perforated strips.

 

[TuXy]

Right thinking about the moment of inertia.

Ears might've been the wrong term. It should be something that looks like a beam shoe, which the beam is laid on for vertical load. But the sides can be longer, so you screw a bit into the beam. Compare the solution with the strap bands.

Got it, then I understood how to compare the beam.

Exactly, ears are more like a classic beam shoe really, where you can screw on both sides of the wooden beam. Possibly also place it on the beam shoe to get stability there as well. Then you could splurge a bit by adding straps that hold the truss together, so it feels like having both braces and a belt.

Need to think a bit more about it all, if it's worth the effort in relation to the aesthetics. You quickly realize how many hours just fly by with everything that comes with it.

 

[StrukturalAB]

Got it, then I had grasped how to compare the beam.

Exactly, ears are more like a classic joist hanger really where you can screw on both sides of the wooden beam. Possibly, you might also place it on the joist hanger to get stability there as well. Then you can spruce it up a bit by adding straps that keep the truss together, so it feels like you have both suspenders and a belt.

I need to think a bit more about it all, whether it's worth the effort in relation to the aesthetics. You quickly realize how many hours just fly away with everything that comes with it.

Indeed, not done in an afternoon. Good luck!

 

[TuXy]

Yes, not done in an afternoon. Good luck!

Thank you so much for that and thank you for the help!

I'll update if I get the saw 😄