FAQ – Questions and answers about fire protection coatings

Increasing heating in case of fire leads to a reduction in the load-bearing behaviour of steel components. When the critical steel temperature is reached, there is a risk of failure, i.e. loss of load-bearing capacity occurs. Fire protection coatings extend the time until the critical temperature is reached as long as possible or as long as necessary.

The coatings foam up when exposed to heat (from approx. 200°C) and form an insulating carbon foam.

• The architectural beauty of steel structures is emphasized because the coatings are applied profile-following. This makes complex geometric shapes easier to execute.
• The layer, which is thin from 0.2 mm, is used in the static calculation due to its low weight. is not taken into account in the static calculation.
• The installation time is reduced by a workshop coating.
• Individual colouring is possible due to the top coat.
• The fire protection coating is maintenance-free.
• The intumescent is up to 10 times faster in application than fire protection panels.
• Easy to clean due to the smooth surfaces with top coat.

As mechanical damage can be largely ruled out, maintenance is not necessary as long as no water damage occurs.

We recommend first removing loose dust or other dirt by hand or mechanically, for example by blowing, vacuuming or light brushing. However, care must be taken to ensure that the coating is not damaged. Further cleaning is product-dependent and must be agreed with the respective manufacturer.

No maintenance is necessary. The top coat must be checked regularly to ensure that it is undamaged. Damage to the coating structure must be repaired professionally without delay. The manufacturer’s instructions must be observed. The owner of the object is responsible for the inspection.

• Component temperature not below + 5°C, maximum + 40°C
• Relative air humidity max. 80
• Dew point distance during processing and drying ≥ 3 K
• Protect the coating from weathering (rain) until the entire coating is finished and fully cured!
• Ensure sufficient ventilation.

The above mentioned conditions are product-dependent. The manufacturer’s instructions must be followed.

A general statement on this is not possible. The manufacturers provide information as to whether systems with or without top coat are permitted.

In order to obtain the building authority approval for exterior intumescent materials, outdoor exposure of coated steel plates is required. After 2, 5 and 10 years, aged plates are officially tested again and the approval is then extended accordingly. The system must always be provided with the top coats prescribed by the respective manufacturers.

In the case of small gaps, it can be assumed that the intumescent will bridge them by foaming in the event of fire.

The surface in the gap should be coated as deep as possible.

For larger gaps, the gap should be filled with mineral wool (melting point > 1,000 ° C). Overcoating with intumescent is recommended for optical reasons.

The profile factor is defined as the ratio of the flamed circumference to the cross-sectional area of the profile. There are tables for the commonly used standardized profiles.

Thin-walled profiles with a correspondingly large profile factor heat up more quickly and therefore require thicker layers of the intumescent with correspondingly better thermal insulation.

This required layer thickness depends on several factors. These include, among others:

• the profile factor (U/A factor),
• the type of profile (closed/open),
• the desired fire resistance duration,
• the product used (manufacturer-dependent and regulated by approval),
• the required standard (DIN, EN),
• the rated temperature (EN).

Different profile types (open or closed profiles) have different heating behaviour. Closed profiles heat up faster than open profiles with the same U/A factor. This is taken into account by the appropriate thickness of the insulation layer former.

The maximum fire resistance duration that can be achieved through the use of intumescent materials depends, among other things, on the underlying standard:

• According to DIN: F30, F60, F90
• According to DIN EN: up to R180
• International to 180 minutes.