أخبار الشركة عن Wind and Snow Load in Steel Space Frames: Why Project Location Comes First

Why Project Location Matters

Wind and snow are not fixed properties of a building — they depend on where the building stands. Two identical space frames, one in a coastal storm area and one in a dry inland region, face completely different loads and may need different member sizes and nodes. This is why the first question in any space frame load discussion is: where is the project, and what does the local standard require? Getting that right prevents the two most common errors — overbuilding for a load that will never occur, or underbuilding for one that will.

Wind Load

Wind load depends on the wind speed and exposure at the site, the height and shape of the building, and whether the location is open, suburban, or urban. On a space frame, wind acts as both pressure and suction, and uplift can be significant on large, exposed roofs. The value used in design comes from the project country's wind loading standard, not from a supplier's default.

Snow Load

Snow load depends on the ground snow level of the location and on the roof shape. Flat roofs and valleys can hold more snow; arched and domed roofs shed it differently; and drifting can concentrate snow where it would not naturally settle. The design snow load must be taken from the applicable standard for the site, including drift where the geometry calls for it.

Roof Shape

Roof shape changes how both wind and snow act. A curved space frame distributes and sheds loading very differently from a flat one, so the same span can behave quite differently under the same weather. Shape also affects where drifting and suction are strongest, so it must be considered alongside the load values, not after them.

Span

As span increases, member forces grow quickly, so wind and snow that would be modest on a short span can become governing on a long one. This is why large-span space frames are more sensitive to the accuracy of the wind and snow figures than smaller buildings, and why a rough estimate is rarely good enough.

Support Conditions

How the frame is supported — columns, walls, or free edges — affects how it resists lateral wind and how reactions reach the foundations. The support layout must be known before the load design can be completed, because it changes the load path through the whole structure.

Roofing Dead Load

The weight of the roof panel system, whether metal panels with EPS, PU, or Rockwool insulation, is a permanent load that combines with wind and snow. It must be included as dead load alongside the environmental loads, since it can shift which combination governs.

Load Combination

Real structures rarely experience one load alone. Standards define combinations — for example dead plus snow, or dead plus wind — and the design must check the governing combination rather than a single load case. Some combinations govern one member while others govern another, so the whole frame has to be verified, not just the most obvious parts.

Load Inputs at a Glance

The table below summarises where each load input comes from, so nothing is assumed:

Structural Calculation

The final step is a structural calculation that turns these inputs into member sizes, node details, and connections. Space frame design uses this calculation to confirm that every member and node can carry the combined loads safely, and to document that the frame matches the standard it was designed to.

Follow the Project Country's Standard

Above all, the final design must follow the project country's applicable structural standard. Wind and snow values, load factors, and combinations differ between standards, so a design that is correct in one country may not satisfy another. The professional approach is to state the location and the governing standard at the outset, and let the design follow that standard rather than a generic assumption — so the space frame is safe, verifiable, and accepted by the local authority without argument.