Long stringers for outdoor stairs on a slope

[Krombacher]

Hello!

I was planning to build an outdoor staircase on this slope (see image). The plan was to use pressure-treated joists 45x220 as stringers. The problem is that they need to be over 6 meters, but the longest I can find is 5.4 meters of this type in the hardware store.

Any ideas?

 

[Petteri Koste]

Splice as in the thread A patio deck project at the summer cottage
https://www.byggahus.se/forum/threads/ett-traedaecksprojekt-vid-sommarstugan.260414/
Saw out triangles and screw and glue onto the stringer. One tread + 2 risers (Heights) should have a total of 63 cm. Then it will be comfortable to walk on.

 

[hackatall]

Lightning joint maybe? Works best on logs but I have successfully used the technique when I want "long" planks. Pre-drill and screw in long spax that hold the joint together.

 

[Willewonka]

You can't place a plint in the middle? So you take 2 pieces of 3.6m and splice over a plint?

 

[Autodidak1]

Hello!

I was planning to build an outdoor staircase on this slope (see picture). The plan was to use pressure-treated beams 45x220 as stringers. The problem is they need to be over 6 meters, but the longest I can find at the hardware store is 5.4 meters.

Any ideas?

Contact any larger hardware store and order 6-meter finger-jointed beams. I've personally ordered 10 of these from Beijer.

I noticed you need over 6 meters, I'm not sure how long they can be obtained.

 

[Willewonka]

Contact any (larger) hardware store and order 6-meter, finger-jointed. I have personally ordered 10 of these from Beijer.

I saw that you need just over 6 meters, I'm not sure how long they can be obtained.

Treated?

 

[Autodidak1]

Printed?

Yep

 

[Krombacher]

Thanks everyone for the input!

What do you think about screwing together two 45x220 so that the vangstyckena together become 90x220. This would mean requiring 4 "pieces" per vangstycke, two long and two shorter ones that you overlap, so there is a joint at the top of one "half" and a joint "down" in the other half.

 

[Krombacher]

Splice as in the thread A deck project at the summer cabin
[link]
Saw out triangles and screw and glue onto the carriage piece. One tread + 2 risers (Heights) should have a sum of 63 cm. Then it will be comfortable to walk on.

Thank you Petteri for your response!
I was thinking of having the treads inside the carriage pieces, then I think it would be a bit strange with such a splice. But what do you think about my suggestion with double 45x220 that I have written below (or if it ends up above...)?

 

[Autodidak1]

Thanks everyone for the input!

What do you think about screwing together two 45x220 so that the stringers together become 90x220. This would require 4 "pieces" per stringer, two long and two shorter that you would lay overlapping so that there's a joint at the top in one "half" and a joint "down" in the other half.

That works great, but check if it wouldn't be cheaper and easier with a pressure-treated glulam beam.

 

[Krombacher]

It works perfectly, but check if it might be cheaper and easier with a pressure-treated glulam beam.

Hmm, I'm googling around a bit and not finding a huge range of pressure-treated glulam. Do you mean it would have to be custom-ordered?

 

[Autodidak1]

Hmm, googling around a bit and not finding a huge selection of pressure-treated glulam. Do you mean it needs to be custom ordered?

Once again, just talk to the building supply store, most of it is available

 

[Petteri Koste]

How many plinths were you considering in total? I think the staircase might wobble a bit if you don't have support at 3 points. More material consumption with that setup inside but maybe nicer?

 

[Krombacher]

How many posts were you planning on, in total? I believe the staircase might wobble if you don't have support on 3 points. More material usage with the internal setup, but maybe it looks better?

I was thinking of 3 posts (per stringer, so a total of 6 support points). I've probably decided now to use double 45x220 so it becomes 90x220. The question is just what screws are suitable to join two 45x220 together?

 

[Willewonka]

I had planned for 3 foundations (per girder, so a total of 6 support points). I have probably decided now to go with double 45x220, so it becomes 90x220. The question is just the suitable screw to join two 45x220?

Wood glue for outdoor use and type 6x80 wood screws? Alternatively through-bolt with washer and nut/French screw, but feels like overkill.