Loads On Roof Structures
And How To Apply Them ⚠️⚠️
Hi friends, ✌️✌️
We have already covered what loads are generally considered in the structural design of buildings.
Today, we’ll specifically look at loads on roofs and how you apply them to an inclined static system, because most of the loads are applied differently. ↘️⬇️⬆️
We’ll use a purlin roof as an example. 👇👇
#1 Snow load
The snow load is calculated according to EN 1991-1-3. The load acts vertically and is distributed horizontally.
Check it out. 👇👇
You can follow 👉👉 this guide 👈👈 to see how to calculate the snow load for pitched roofs.
#2 Wind load
The wind load is calculated according to EN 1991-1-4. We also made a guide for the wind load calculation of pitched roofs, which is more work than the snow load. 😉😉
The wind load is always applied perpendicular to the surface of the structure. Whether the direction of the wind load is towards the surface or away depends on the area of the roof, which are shown in Eurocode.
#3 Dead load
The dead load (self-weight) is often given by manufacturers or calculated by the density of the material.
The dead load acts vertically while it’s distributed along the beams/roof slope.
#4 Live load
The live load is defined in EN 1991-1-1. It depends on the category of the building and the country you design your structure in.
The live load of a roof includes maintenance work, for example.
It’s applied as the dead load.
#5 Load combinations
After you have calculated the characteristic loads in steps #1 - #4, you need to set up load combinations, which combine the different loads and add safety factors.
Check out our step-by-step guide on how to do load combinations.
Finally, when the load combinations are set up, we are ready to design the structural elements of the roof. 🔥🔥
This was it for this week.
I hope it gave a good understanding of what loads need to be considered in the design of inclined roofs.
See you next week. 😎😎
Cheers,
Laurin.