Pleated    Structures

Pull down cables

Using "push-down" valley cables can have some disadvantages under some circumstances.

An alternative pattern employs "pull-down" cables.

These are cables that pull the fabric down from below - rather than pushing it down from above.

To do that a cable sheath is required. This is stitched, glued or welded to the bottom of the fabric.

Valley cables
Pull down cables

Pros and cons

Like the related flat pattern there are some adavantages - and some disadvantages - to this pattern - when compared to the use of push-down valley cables.


  • The cables are kept on the inside - which helps avoid corrosion and thermal damage;

  • The pull-down cables are better placed to interact with internal structural elements;

  • The cables can be thermally insulated from the main membrane - helping to prevent heat damage.


  • Using pull-down cables incurrs additional construction costs, due to the cable sleeves;

  • Assembly is also more complex - due to the need to pass the cables through the sleeves.

In many respects the key feature of the idea is that it makes it easier for large anticlastic surfaces to be pleated.

Anticlastic surfaces are important because they are light - and can be constructed with tensile-only elements.

However, in pleated structures making anticlastic surfaces requires that the membrane be pulled down from below - and unless 'pull down' cables are used, that is difficult to do without damaging or penetrating the fabric.


It's not always easy to tell from photographs whether structures are using pull-down cables - however these structures certainly look as though they are:

Myao Li Arena
Myao Li Arena

Talisman centre
Talisman centre

Both these structures feature large anticlastic surfaces.

It appears that pull-down cables have been used in these structures because of the way they facilitate those cables interacting with transverse interior cables.

Pull up cables

If you can replace ordinary valley cables with pull down cables, it makes sense for you to also be able to replace ridge cables with pull-up cables.

Although the elements in question appear to be compression members, pleats in a membrane being pulled upwards appears to be going on here:

Ichinoseki industrial centre
Ichinoseki industrial centre

Tim Tyler | Contact |