Fixing sprinkler pipes: which clamps and anchors does NEN-EN 12845 require?

7 min read

When a sprinkler installation is handed over, the clamps and hangers are often the first thing checked. Yet there is little Dutch guidance that translates the requirements of the standard into concrete products. Below you read what NEN-EN 12845 asks of pipe supports, which Fischer clamps and anchors fit, and where things often go wrong at inspections.

Which standard applies?

In the Netherlands, NEN-EN 12845:2015+A2:2026 is the usual standard for sprinkler installations. The standard covers design, installation and maintenance, and most certification bodies assess against it.

You also come across two other families of standards. The VdS guideline CEA 4001 comes from the insurance sector and is close to NEN-EN 12845. The FM requirements (FM Data Sheet 2-0) follow the American NFPA 13. The client and the insurer decide which standard applies.

What does NEN-EN 12845 ask of the hangers?

The standard has its own chapter on pipework and its supports. We do not give its figures here: you read them in the standard itself and in the approved design of your installation. These are the requirements you meet most often on site.

Distance between support points

For each pipe material and diameter, the standard gives a maximum distance between support points. Keep to that table, or to the distance in the approved design, and add an extra support point if in doubt.

Also look at the couplings. A grooved coupling needs a support point close by. This is often missed, because clamps are set at fixed distances without taking the couplings into account.

Not simply to profiled steel sheet

A profiled roof deck is not designed for the weight of a filled sprinkler pipe. Fix heavier pipes to the load-bearing structure, such as beams and purlins. The standard and the design decide what you may hang from the roof deck.

For lighter pipes there are hangers approved for trapezoidal sheet, such as the Fischer TZ and KDS. Check the permitted load and the approval mark for each size.

Load capacity of the hanger

A hanger must carry well over the weight of the water-filled pipe and of the hanger itself. The safety factor for this is in the standard and in the design. So use only clamps and anchors with a known permitted load. Clamps that are not approved or not calculated are a reason for rejection at inspection.

Which Fischer clamp for which situation?

The approval marks in this table come from the product data in our webshop. With beam clamps, follow the installation instructions: in VdS installations, locking plates are required from DN65.

Anchors per base material

Concrete ceiling

The pipe usually hangs from a threaded rod with an anchor in the concrete ceiling. For sprinkler work, choose an anchor that is approved for cracked concrete under its ETA:

• FAZ II Plus bolt anchor: for heavy loads in cracked and non-cracked concrete, also under seismic loading.
• FZEA II hammerset anchor: for cracked and non-cracked concrete with a shallow drilling depth, fire resistance R120.

Hollow-core slab floor

Steel structure

To steel beams you fix with a beam clamp, such as the TKL, or the TKLG for sloping beams. You then do not need an anchor. Measure the flange thickness first and choose the clamp to suit it.

Five mistakes that often stand out at inspections

1. No support point at the grooved coupling. The clamps are at fixed distances and the couplings are forgotten.
2. Heavy pipes on steel sheet. They belong on the load-bearing structure, not on the roof deck.
3. No FM approval mark in an FM system. If an FM approval exists for that component, the FM Approved component must be used.
4. The wrong anchor in a hollow-core slab floor. An expansion anchor in a hollow core does not hold.
5. No documentation. After handover, you must be able to show which materials were used. Keep ETA numbers, certificates and photos of the fixing points.

From standard to order

NEN-EN 12845 sets clear requirements: maximum distances between support points, attention to the couplings, enough load capacity and limits per base material. You read the figures in the standard and in the design. With the right Fischer clamp and an anchor with an ETA, you meet them. Not sure exactly which product you need? Describe your situation in the Product finder.

This article is general information, not design advice. The text was checked on 21 October 2026 against the sources below. The design of your installation and the certifying body decide what applies in your project.

Sources

• NEN-EN 12845:2015+A2:2026, the standard for sprinkler installations (NEN)
• FM Global Data Sheet 2-0, Installation Guidelines for Automatic Sprinklers
• fischer product page beam clamp TKL M12: approvals and permitted load per size (in German)
• fischer product page beam clamp TKLS Steel Bite (in German)
• fischer product page profile hanger TZ M8 (in German)
• fischer product page spring toggle KDS (in German)
• fischer product page hammerset anchor FZEA II (in German)
• fischer product page bolt anchor FAZ II Plus (in German)
• Product data and approvals per product: the Certification property in our webshop