We have a new download available on our Formwork Downloads page  – Doka form-ties for special requirements.

This User Information booklet (Method Statement) is aimed at everyone who will be working with the Doka form-ties for special requirements. It contains information on how to set up this system, and on correct, compliant utilisation thereof.

Preliminary remarks

To pour walls, it is necessary to have wall-ties with sufficient load-bearing capacity. In general, a distinction is made between:
● wall-ties where no special requirements are made – these only need sustain the pressure of the fresh concrete – and
● wall-ties for special requirements that are fulfilled by additional measures aimed at making the tie-points e.g.:
– water-impermeable
– fire-resistant
– sound-insulating
– gas-impermeable
– radiation-proof

This manual offers ideas and suggested solutions for form-tie points that need to meet one or more of the requirements stated above.

● Choosing a suitable formwork system with a widely spaced form-tie pattern is one way of reducing the number of expensive wall-ties that are needed. This will, of course, depend upon the circumstances and requirements applying on each site.
● If the main sealing function is intended to be in the middle of the wall (in the same way as with joint-sealing tape), this has the advantage that the form-tie point is watertight from the moment the formwork is stripped.
● Sealing measures that are carried out on the outside only, e.g. by bonding, call for extremely skilled, painstaking work.
● Tie-holes with small conical openings are more pleasing to the eye (fair-faced concrete) and easier to close off.
● In order to ensure that the wall-tie fulfils the requirements made of it, the points below must be followed, regardless of which design variant is selected: – the wall-tie must be precisely defined in the tendering documents – the relevant regulations and standards must be observed – the manufacturer’s installation instructions must be followed – the personnel involved must be sufficiently skilled.