Structural engineer type question.

[Bill Douglas]

Well, your help is much appreciated. Very much appreciated.

[look 171]

I had to google 5 meters

That steel is 100mm, so that's about 4+ inches. The span is 16'. That's a bit long but I am not an engineer. My fear is flex and sag. Only 3/16 thick or 4mm? Im not an engineer so I am waiting for the smart folks for their calc

[john70t]

I was looking at some car ports on the internet.
-One was rated at 75mph wind.

-A similar looking one from a major box store was rated at 25 mph.
(Yeah you read that correct. US Government federally-approved. 25mph.)
Your car might have mandated crumple zones and seat belts and airbags and and tire pressure monitors and computer ABS, but you will still get crushed just sitting there in the driveway.

-A good looking chinese knock-off was rated at 7mph after much digging at the specs.
The metal pieces were paper-thin upon further visual inspection.
Serious WTF territory.

[john70t]

The manufacturer should have a quick answer if that I-beam will span that distance.
And what the spacing should be.
I would email them.

[Bill Douglas]

5 meters = 5 yards and a bit haha.

Good thinking re email the manufacturer.

Or I could up size it a little from 100mm to 125mm web (height).

[look 171]

Judging from those numbers, I would up size a bit jsut to take the flex out. Glass do not like to be flexed, well, not that much. Get Low E glass.

[Bill Douglas]

Yes, this particular glass is weird stuff, it's old windows from a tower type office building in town. I accidentally broke a couple a couple of sheets and they sounded like a pistol bullet going off and broke up into dice sized pieces like car windows used to.

Either that or the neighbor was shooting at me and got the glass instead.

[look 171]

Originally Posted by Bill Douglas

Yes, this particular glass is weird stuff, it's old windows from a tower type office building in town. I accidentally broke a couple a couple of sheets and they sounded like a pistol bullet going off and broke up into dice sized pieces like car windows used to.

Either that or the neighbor was shooting at me and got the glass instead.

How did you break it? Must be tempered glass. Did you sit the edge on concrete and it shattered? Ask me how I found out.

[look 171]

I am not sure about putting that glass on top especially if its 16' or 5 meter span? That's a lot of glass if it goes. I know you already have it on hand, but I would seriously consider new pieces like a laminated glass like a windshield. I wouldn't put that in someone's house. Too much liability especially without engineering or stamping their name in blood on this one.

[Bill Douglas]

One sheet I had the glass clamps (things you pick up sheets of glass with) too close to the edge and I think it put a slight bend i the glass and created a weak point on the edge. the other one I very slightly tapped it on the edge with a hammer. LOL although it was a hammer I barely tapped it.

[Bill Douglas]

We are pretty rough here in NZ. We re use a lot of stuff to save money - and to make projects happen that would otherwise be unaffordable.

[look 171]

Originally Posted by Bill Douglas

We are pretty rough here in NZ. We re use a lot of stuff to save money - and to make projects happen that would otherwise be unaffordable.

I am in a different situation then you, Bill. I have to delivery a safe product or else I will be in some deep poo. You should see when I bought my home 20 years ago at age 29, a total fixer. I used whatever possible knowing is good enough for a few years, I did it. Do it again or right when the money comes through at a later day. Got married a few years later, then I got serious because there's someone else in the house and kids will be coming, so I tore it out and rebuild everything taking out the sharp edges. I rebuild about 90 % of my house because of "Those people"

What do you mean by pretty rough? The economy is still strong down there before covid?

[look 171]

Originally Posted by Bill Douglas

One sheet I had the glass clamps (things you pick up sheets of glass with) too close to the edge and I think it put a slight bend i the glass and created a weak point on the edge. the other one I very slightly tapped it on the edge with a hammer. LOL although it was a hammer I barely tapped it.

Sounds like tempered glass. It exploded into a thousand little pieces?

[john70t]

Early Pyrex baking dishes did that. I had that happen.

[Bill Douglas]

Originally Posted by look 171

What do you mean by pretty rough? The economy is still strong down there before covid?

Maybe I should describe us as "overly practical".

Yes, the economy is fine, were doing OK. A good standard of living around the place.

Maybe it is tempered glass. It broke like car windscreens used to break back in the 1970's. Yes a thousand little squares.

[look 171]

Originally Posted by Bill Douglas

Maybe I should describe us as "overly practical".

Yes, the economy is fine, were doing OK. A good standard of living around the place.

Maybe it is tempered glass. It broke like car windscreens used to break back in the 1970's. Yes a thousand little squares.

You must watch too much American TV. We are portrayed as living large in million dollars beach front properties. That's not true at all. Across the nation, we are a pretty practical group.

[Bill Douglas]

Haha, we grew up on American TV. Walt Disney comics...

GF watches Million Dollar listings (Altman brothers) I have real trouble explaining to her that not all of the US is like that. I've been to about 12 states, and stepped foot in Mexico and Canada, so I'm pretty realistic about what goes on in the place.

[3rd_gear_Ted]

Design factor in some cases:
I have a similar structure on my ocean front home in Baja MX.(Solarium)
Had to take into consideration the condensation that occurs on the inside surface certain times of the year (foggy/sunny days)
Installed evaporation trays on low end of properly angled panes, to low a pane install angle leads to dripping instead of laminar flow on inside glass surface. Condensate flows into trays and evaporates instead of drip marks on wood tile.

No bad days in Baja, peace, love & fish tacos

[1990C4S]

I would make the feet adjustable or shimable.

There are span and load charts online...and formulae...

[kach22i]

Originally Posted by 1990C4S

There are span and load charts online...and formulae...

Yes, find and use those like a professional would.

Notice closely the "T" brackets at the top of the columns in the original post as well. These eliminate need for diagonal bracing.

At the bottom of the column will be equal measures as well.

These not only laterally stabilize the structure they work to transfer UPLIFT loads.

The roof acts like an airplane wing, hence the reason for tie-down straps and brackets in the building code.

Oshkosh Archives - Arizona Flight Training Workgroup


Precautions taken at the Oshkosh Airventure to tie aircraft down and ballast them may serve as a reminder.

Similarly your footings should be sized not only for gravity loads but for uplift as well.

If you pay a structural engineer for a couple hours of review time it will be well worth the $120 an hour in my opinion.