---
title: "Which screw should I use for sheet metal?"
description: "A self-drilling (Tek) screw with a drill point matched to the material thickness, or a self-tapping screw into a correctly sized pilot hole. The ranked options, the "
url: https://atoneplace.net/which/screw-sheet-metal/
site: "At One Place"
---

# Which screw should I use for sheet metal?

**Which screw should I use for sheet metal?: A self-drilling (Tek) screw with a drill point matched to the material thickness, or a self-tapping screw into a correctly sized pilot hole.**

A thread cut in sheet metal has very little engagement — in 1 mm steel a screw has one thread of grip — so almost all the strength comes from the sheet, not the screw. That is why thin material calls for rivets or rivnuts rather than more screws, and why over-torquing strips a self-tapper instantly and permanently. Self-drilling screws are specified by point size for a thickness range, and using one outside its range is the usual cause of a screw that spins without penetrating: the point work-hardens the sheet, and once the surface is glazed, nothing will start. Coatings matter outdoors, since a screw that breaches a galvanised sheet becomes a galvanic couple and rusts around the hole.

## The options, ranked

*Ranked best-first for the stated job. The third column is why the others exist.*

| Option | Good at | Bad at |
| --- | --- | --- |
| Self-drilling (Tek) screw | Drills, taps and fastens in one action, which is why steel framing goes up so quickly. | The drill point is sized for a thickness range; too thin and it strips, too thick and the point wears out before it penetrates. |
| Self-tapping screw into a pilot hole | Precise and reliable, and the right approach in thicker or harder material. | Needs the correct pilot size — too small strips the screw, too large strips the thread. |
| Rivet | Vibration-proof and flush, and the aviation and bodywork standard for thin sheet. | Permanent, and it needs access to both sides for some types. |
| Machine screw with a nut or rivnut | Repeatedly demountable and much stronger in thin material than any thread cut in the sheet itself. | Needs access behind, or a rivnut tool. |

## Technique that changes the outcome

1. Match the drill point size to the sheet thickness
2. Use steady pressure and low speed so the point can cut rather than skate
3. Clamp the sheets together first; a gap means the screw drills the second sheet away from the first
4. Deburr and, outdoors, seal around the head

## What goes wrong

- Over-torquing, which strips the thread in one turn
- Using a self-drilling screw outside its thickness range
- Plain steel screws in galvanised or aluminium sheet, which corrode galvanically

> Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.

## Other screw questions

| For | Use |
| --- | --- |
| Wood | A pilot hole matching the screw's core diameter in the lower piece and a clearance hole in the upper one — that is what makes a joint tight. |
| Decking | Stainless steel — 304 inland, 316 near the coast — or a screw specifically rated for modern treated timber, which eats ordinary zinc plating. |
| Masonry | A concrete screw into a precisely sized hole, or a plug and screw — and hollow block needs a different anchor entirely. |
| Plasterboard | Coarse-thread bugle-head drywall screws into timber studs, fine-thread into metal studs — and never use them for anything structural. |
| MDF | A straight-shank MDF screw with a parallel thread, always into a pilot hole — the edge splits without one. |
| Chipboard | A twin-thread chipboard screw with an unthreaded shank under the head, so it pulls the joint together instead of bursting the board. |
| Plastic | A thread-forming screw designed for plastic, or a heat-set threaded insert where the joint will be undone more than once. |
| Roofing sheets | A hex-head screw with a bonded EPDM washer, driven until the washer just spreads — no further. |
| Brass hardware | Cut the thread with a steel screw of the same size first, wax the brass one, and use a driver that fits the slot exactly. |

## Common questions

### Which screw should I use for sheet metal?

A self-drilling (Tek) screw with a drill point matched to the material thickness, or a self-tapping screw into a correctly sized pilot hole.

### What should I avoid?

Over-torquing, which strips the thread in one turn Using a self-drilling screw outside its thickness range Plain steel screws in galvanised or aluminium sheet, which corrode galvanically

## Related pages

- [Which screw and pilot hole should I use for wood?](https://atoneplace.net/which/screw-wood/)
- [Which screw should I use for decking?](https://atoneplace.net/which/screw-decking/)
- [Which screw should I use in masonry?](https://atoneplace.net/which/screw-masonry/)
- [Which screw should I use for plasterboard?](https://atoneplace.net/which/screw-plasterboard/)
- [Which screw should I use in MDF?](https://atoneplace.net/which/screw-mdf/)
- [Which screw should I use in chipboard?](https://atoneplace.net/which/screw-chipboard/)
- [Which screw should I use in plastic?](https://atoneplace.net/which/screw-plastic/)
- [Which screw should I use for roofing sheets?](https://atoneplace.net/which/screw-roofing/)
- [How do I drive brass screws without snapping them?](https://atoneplace.net/which/screw-brass-hardware/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)