Hello everyone!
Where can one find a structural engineer who can calculate the load-bearing capacity for my extension that I will build myself? Or should I just consult a carpenter? I will make the trusses myself and need calculations for a load-bearing beam under the floor of the upper floor.
Where can one find a structural engineer who can calculate the load-bearing capacity for my extension that I will build myself? Or should I just consult a carpenter? I will make the trusses myself and need calculations for a load-bearing beam under the floor of the upper floor.
Best answer
Call a company that provides such services?
Some major ones are Tyréns, Wsp, and Sweco. It shouldn't take many hours of work to calculate a few roof trusses. How advanced is the extension?
There are many skilled people here on the forum who can also help calculate some simple roof trusses/beams....
Some major ones are Tyréns, Wsp, and Sweco. It shouldn't take many hours of work to calculate a few roof trusses. How advanced is the extension?
There are many skilled people here on the forum who can also help calculate some simple roof trusses/beams....
The beam should be an IPE or HEA otherwise it was a good link. It would have required an LT 140x270 if it were to hold. And it would have resulted in a ceiling height of 183 cm under it, so it's a bit low. The span of the beam is 3.5 meters and the distributed load should be 200kg/sqm in residential buildings I have read, and that would be about 4 tons.
You can find tips about roof trusses on the wood guide if it's a common model.
Regarding the beam, it is fairly easy to calculate this; you don't need to be a doctor in strength of materials. Normally, you design against deflection. 200kr/m2 is a common rule of thumb, then you can add a bit for the self-weight in the joist floor. Upload a drawing or dimensioned image of the construction, and I can calculate it.
Regarding the beam, it is fairly easy to calculate this; you don't need to be a doctor in strength of materials. Normally, you design against deflection. 200kr/m2 is a common rule of thumb, then you can add a bit for the self-weight in the joist floor. Upload a drawing or dimensioned image of the construction, and I can calculate it.
Buy the roof trusses and get the calculations included, that's my advice.
The reason I think you should buy the trusses is mainly because you might not even make them cheaper yourself. And then, if you still buy, the truss manufacturer will simply calculate for you. 
We assume the load is 4 tons, evenly distributed, span 3.5m and a simply supported beam. Acceptable deflection is 8.7mm (3500/400). With an HEA160, you get a deflection of 6.2mm. With an IPE180, you get a deflection of 7.9mm. However, I suspect that you have made a mistake with the load, as only half the floor load affects the beam (if it is in the middle), the other half affects the outer walls.
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