Which penetrations are most common in non-residential buildings?
| Penetration | Point of attention | Common solution |
|---|---|---|
| Cable trays and cable ladders | Large bundles, and cables are often added later. | Coated mineral wool boards or fire-resistant pillows or blocks, following the prescribed build-up. |
| Plastic drain and rainwater pipes | The material softens in a fire and leaves an open hole. | Fire collar or wrap; for certain pipes a sealant substantiated for that use. |
| Metal pipes (sprinkler, heating, cooling) | Metal conducts heat to the other side; the insulation counts. | Seal with the insulation as the system prescribes, often over a certain length on both sides. |
| Mixed openings | Cables, trays and pipes together in one opening. | A combination seal, for example coated mineral wool board with collars, substantiated for the whole combination. |
| Ventilation ducts | The duct itself must not weaken the separation. | A fire damper or a fire-resistant duct; the space around it according to the damper's installation instructions. |
Read more about choosing between systems in fire collar, sealant, mortar or PU foam and about dampers in fire dampers.
Lightweight partitions and suspended ceilings
Many fire separations in offices and healthcare buildings are metal-stud walls with plasterboard. A seal in such a wall must be substantiated for that wall build-up: the thickness, the number of board layers and sometimes the wall's infill. A system tested in a concrete wall does not automatically apply in a plasterboard wall.
In addition, the separation itself must be continuous. A compartment boundary that stops at the suspended ceiling is open above it, however well the penetrations are sealed. That is why our survey also looks above the ceiling and under the raised floor. More on this in fire compartmentation in non-residential buildings.
Tenant fit-out and later changes
In an office or commercial building, handover of the shell is rarely the end. During tenant fit-out and later alterations, new cables and pipes pass through existing fire separations. Whether a cable may be added through an existing seal depends on the instructions of the system.
If you anticipate this, you choose a system that allows additions in places that change a lot, and record every seal with a number and a photo. Then for every change you can check what is there and what is allowed. That is the basis of our digital logbook.
Standards for penetrations
Penetration seals are tested to NEN-EN 1366-3 and classified to NEN-EN 13501-2; NEN-EN 15882-3 describes how extended applications are substantiated. Fire dampers have their own standards (testing to EN 1366-2, product standard EN 15650). The WBDBO between spaces follows from NEN 6068, smoke resistance from NEN 6075. Which WBDBO a separation must achieve is set out in the fire safety concept; we work from the drawings and the concept you supply.
