TFF Female-Head Concrete Screw
Direct-fastening concrete screw with an internally threaded (female) head – for suspension, pipework and hangers.
What is a Female-Head Concrete Screw?
The TFF is part of the TF concrete screw family – the same direct-fastening technology and the same approvals – but instead of a male head (hex, dome, countersunk) it comes with an internally threaded female head.
What that means on site: drill, drive the screw into the concrete, then thread a rod, a hook or any other element into it. The suspended element is installed after the anchor, and can be replaced without touching the anchorage itself.
Applications
Suspending pipework and ducting
A threaded rod screws straight into the head – water pipework, cable trays and HVAC ducting.
Fire-suppression systems
Sprinkler anchoring backed by the CSIC certificate.
Hollow-core slabs (Spancrete)
Direct anchoring into prestressed and hollow ceilings, backed by ETA6.
Multi-point systems
Approved for redundant non-structural systems – modular partitions and building services.
Hangers and rails
Elements that will be replaced or removed later, without touching the anchorage.
Flush in the ceiling
The anchor sits flush against the concrete face – nothing protrudes.
Technical Specification
| Characteristics | Direct-fastening concrete screw with an internally threaded (female) head |
| Material | Carbon steel, grade 8.8 |
| Coating | Zinc plated (TFF). Also available in the Atlantis coating and in SS316 stainless steel (TXF) |
| Technology | Direct fastening |
| Cracked concrete | Yes |
| Seismic loads | Yes – C1-C2 |
| Re-usable | Yes |
| Fire standard | Yes – R120 (Efectis) |
| Approvals | ETA1 for cracked and uncracked concrete · ETA6 for hollow-core · CSIC for sprinklers |
Coating Versions
Files to Download
- Concrete screw – technical data (English)
- European Technical Assessment (ETA) – cracked and uncracked concrete
- ETA 6 – prestressed / hollow-core slabs
- CSIC certificate – sprinklers
- Declaration of Performance (DoP)
- AutoCAD files
TFF vs. the HC and HE-HC Female Anchors
This is the most common question. Both give you a female thread in the ceiling – but they work in completely different ways:
| TFF – female-head concrete screw | HC / HE-HC – female anchors | |
|---|---|---|
| Principle | Threads directly into concrete, cutting a mechanical thread | A sleeve / hammer-set anchor that expands inside the hole |
| Removal and re-use | Fully removable and re-usable | The anchor body stays permanently in the base material |
| Installation | A single pass – drill, clean, drive | Needs an extra tool to expand the sleeve |
| Working at height | Less effort and fatigue on scaffolding | Higher effort when working overhead |
Frequently Asked Questions
What is the difference between the TFF and the HC and HE-HC female anchors?
The TFF is a male anchor that threads directly into the concrete, forming an internal mechanical thread, and can be fully removed and re-used. The HC and HE-HC are female sleeve / hammer-set anchors that stay permanently in the base material after installation – only the male bolt that screws into them can be removed and replaced, not the anchor body itself.
Is the TFF suitable for hollow-core (Spancrete) slabs?
Yes – backed by ETA6. The approved sizes (TFE5 and TFE6) are matched to the thin lower shell of a Spancrete slab without damaging the internal prestressing strands.
Is there a stainless steel TFF?
Yes – the SS316 stainless version is called TXF. See the TX stainless steel concrete screw page.
Can the suspended element be replaced without removing the anchor?
Yes. That is the central advantage of the female head – the element threads into the head and can be removed and replaced without touching the anchorage itself.