Iona SkyDome

Structural Designer

Eckersley O'Callaghan

Client Name

Carnival UK


The sea - UK

Martin Francis (Francis Design Limited)

Meyer Werft 

Frener & Reifer


An elliptical dome capable of withstanding extreme weather conditions. The dome was designed to be the focal point on a new ocean liner. It had to be robust enough to withstand conditions that a structure of its size and situation would face at sea. The dome was subjected to strict and uncompromising weight limits. This meant each part had to be carefully detailed and optimised.

Submitted in 2020

Judge's comment:

This glazed dome structure, and its situation are unique as no structure of its complexity has ever been built on a ship before. 

The SkyDome is an elliptical structural steel grid-shell roof made up of equilateral triangles. The shape has been optimized using gravity loading as a form-finding method for the roof geometry.

The engineers expertly negotiated and overcame a number of substantial structural challenges. These included having to withstand severe and changeable weather conditions, vibrations, environmental performance issues and regulatory hurdles. The structure was subjected to strict and uncompromising weight restrictions meaning each part had to be carefully detailed and optimised to stay within the allowable limits. 

Designing the structure involved transferring expertise from the traditional building world and re- applying it in a very different marine setting. The structure has had to prove itself capable of withstanding the extreme conditions that a project of this size and situation will have to face, yet has remained efficient, elegant and refined.


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