How do you calculate how much weight a balcony can bear?

[Rolle85]

I simply wonder if one can say what a balcony can support in weight? The builders put up a balcony frame for me. Here is the situation:

- It is anchored in the ground with concrete foundations at the front. At the back, it is anchored via a support beam into the house's horizontal studs behind the outer panel (220x45).
- Support beam in 220x45.
- 50cc between studs (170x45).
- The front support beam is notched into the posts so that it rests inside them.
- The posts are 125x125 impregnated.

Can one give a rough estimate? Is it possible to calculate?
View attachment 522806

 

[larsbj]

Of course, that can be done.
Normally, one doesn't think like that, instead, one sizes according to a prescribed load that is standard and builds accordingly.
One could probably say that your balcony is on the lower side in terms of dimensions, which doesn't mean it will collapse, but it might flex a little if there are a lot of people, and possibly bend over time.
It should have been double 45x220 in the front beam and 45x220 c30 in the floor structure.
I don't remember exactly what the design load is for a balcony, but I think it's somewhere around 1.5kN/m2, so about 150kg per square meter, so there is a decent margin, which can accommodate many people on yours.

 

[Rolle85]

okay, can I install double studs here and there to help? For example, there are three studs in the middle?

I was looking at someone else's drawing and I found its dimensions on posts/planks quite diminutive compared to mine?

 

[fgo]

The design loads for the balcony are:
3.5 kN/m² and a point load of 2.0 kN.

When I calculated balconies during my studies, I remember that the dimensions of the timber became quite large to handle the loads.

 

[Rolle85]

Okay, should I add double studs?

 

[larsbj]

Dimensional loads for balcony are:
3.5 kN/m² and point load of 2.0 kN.

When I calculated balconies during my study time, I remember the dimensions of the timber became quite large to handle the loads.

I believe the higher figure only applies to a balcony that is of the cantilever type, but I'm not sure.
I'm on vacation so I have no books
TS's balcony is more of a patio and should be dimensioned accordingly.

 

[larsbj]

Ok should I add double studs?

Preferably supplement with 45x220, the best way to eliminate the risk of sagging.

 

[fgo]

I think the higher figure only applies to balconies of the cantilever type, but I'm unsure.
I'm on vacation so I don't have any books
TS's balcony is more like a patio and should be dimensioned accordingly.

These are Swedish wood recommendations for dimensions of the patio deck at cc600

 

[Rolle85]

Okay then I have a problem. I have to start using double 170x45mm since my free spans are 3.29m.

 

[fgo]

Unfortunately, you are having some problems.
It is the height of the joists that affects the most.

Here you have for cc300 note that it is C24

 

[Rolle85]

So how can I retrofit now? Double studs or place a stud under the current one or similar?

 

[witten]

I think it's more of a small terrace than a balcony. Regardless of the terminology, it is dimensioned as a floor slab with two supports, balconies are usually fixed only to the building.

 

[Rolle85]

Now I am worried. How can I retrofit? Double studs?

 

[Rolle85]

I see now that my free lengths are 3.28 and not 3.5m

 

[fgo]

Download the app "lathunden" from any app store so you can experiment.