Questions/Experiences about flat steel stringer staircase

Hello everyone,

for the house we are building in September, we have fallen in love with a flat steel stringer staircase (1 flight, straight, 16 steps made of solid oak, glued parquet). I already have several offers here, ranging between 5000 and 8000 EUR.

One of them is from a metalworker we know from the region.

The offers differ mainly in the exact execution (roughly they are all the same), as well as in the thickness of the steel stringer. The cheapest offer has a 10mm thick stringer. The most expensive one too. The mid-priced one, from our acquaintance, uses 12mm.

His argument: 10mm would swing, you couldn’t really walk on it safely, it would somehow wobble. He generally doesn’t install anything under 12mm and is not really negotiable about that.

The cheapest offer (the company makes a good impression and was also recommended to us) uses 10mm as mentioned. I asked now how it would look with 12mm in terms of price.

The sales guy then called me earlier and asked why I wanted 12mm. I tried to explain it to him. He said, okay, he can offer it. But that would be money down the drain. He had already designed a flat steel stringer staircase with massive granite steps (instead of 4cm wooden steps) and had calculated with 20mm thick stringers due to the weight. His structural engineer then corrected it back to 10mm. That would be enough. And in the end, they made it with 10mm and nothing swung or wobbled there.

Now my question to the group:

[*]How does it look with your (straight) flat steel stringer staircase?
[*]10mm or 12mm thick stringer?
[*]Besides the anchoring at the bottom on the floor or at the landing: Is yours also anchored to the wall?
[*]Experiences?

Regards
Alex

Hello Alex,

what exactly am I supposed to understand by a "Flachstahlwangentreppe"?

Rhenish greetings

I thought the term was known in the construction industry?! Well, then Google it...

Hello Alex,

I thought the term was known in the construction industry?!

Yes, it is. I just wanted to make sure we mean the same type of staircase.

For our house being built in September, we have fallen in love with a flat steel stringer staircase (1 floor, straight, 16 steps made of solid oak, glued parquet). I already have several offers here, ranging between 5000 and 8000 EUR.

Now my question to the group:

[*] 10mm or 12mm thick stringer?

I would forward this question to the structural engineer; only he alone can specify the exact required stringer thickness based on his calculations. The stringers usually run along the sides of the steps.

Rhenish regards

Hello construction expert,

thank you for the feedback.

We are buying the house from A and the staircase from B1, B2, or B3. "My structural engineer" is the one from A. He doesn’t know the staircase, so he can’t say anything about it. I have to rely on what B1, B2, and B3 say.

B1 sells the staircase with a 10mm thick stringer
B2 sells the staircase with a 12mm thick stringer
B3 sells the staircase with a 10mm thick stringer

All staircases are the same length, have the same number of steps (made from the same material and same thickness), and almost the same railing.

B2 believes that 10mm absolutely won’t work: it swings, it feels "weird" to walk on, blah blah. He insists on his 12mm.
B1 and B3 argue for the 10mm because their structural engineers say 10mm is sufficient. Everything is stable and does not swing.

Since I do not assume that straight flat steel stringer staircases across one floor differ that much, I wanted to ask you (who might already have such a staircase) how it is for you:

* How is it with your (straight) flat steel stringer staircase?
* 10mm or 12mm thick stringer?
* Besides the anchoring at the bottom on the floor or at the top on the landing: is it also anchored to the wall?
* Experiences?

Best regards
Alex