What it is not good for

Where another technology is better

Long spans and heavy loads

Where a thin-walled section would need a disproportionate number of members, hot-rolled steel or another system is the logical choice. When HRS is needed alongside LGS.

Where mass is a functional requirement

For certain acoustic, radiation-shielding or vibration tasks, mass is the solution. It then has to be made up — or another structure chosen.

Heavily loaded structures in contact with the ground

Retaining walls, basements, watertight structures: these are concrete tasks.

Where the moisture load is very high

In a permanently wet, aggressive environment the cost of material choice and corrosion protection can take away the advantage.

Where the conditions are not there

Where there is no design discipline

This technology requires decisions closed in advance: everything has to be settled before manufacture. Where the client likes to change things as they go, it will be expensive. Coordination between disciplines.

Where there is no site discipline

The screw spacing, the presence of the bracing, the continuity of the vapour control layer cannot be dropped. Where these are not checked, the structure does not do what the drawings say. Common site errors.

Where there is nobody to design it

There is no catalogue: every project is a bespoke design. Without that the technology does not work.

What should not be left unsaid

Fire is a sensitive point

Not because the structure is bad, but because this part has to be taken seriously — and the route to verification does not arise by itself. Fire protection of thin-walled steel.

The thermal bridge is real

Manageable, but only with continuous external insulation. The steel thermal bridge.

Vibration has to be designed for

A light floor can vibrate unpleasantly if nobody deals with it. Floor vibration.

The point

This technology is not for everything, and it does not need to be. Where it does suit the task, there are few better solutions.