Connections & installation
How to Match a Drill Point to Steel Thickness
Learn how steel thickness, layered assemblies, and product drilling ranges affect screw-point selection before you order fasteners for a project.
Begin with the steel being drilled
Point selection begins with a material description. Identify the steel layers the screw will penetrate and distinguish those layers from insulation, spaces, or other materials in the assembly. Do not replace a documented thickness with an approximate trade gauge when the actual product specification is available.
A small connection sketch is often more useful than a long email. Label the attached material, supporting member, each steel thickness, and any gap. Add the drawing detail number and proposed screw designation. This gives the manufacturer or reviewer a shared picture of the condition instead of requiring them to reconstruct it from a shopping description.
Understand the drill point's limited job
The cutting point must make the hole before the threaded portion engages as intended. Simpson Strong-Tie's explanation also identifies chip clearance and point geometry as important to drilling performance. This is why the visible point length cannot be treated as extra usable thread engagement.
Keep this drilling question separate from screw length and connection capacity. A fastener can satisfy one check and fail another. A comparison worksheet should therefore have separate boxes for drilling suitability, attachment thickness, connection approval, and environmental compatibility, with a reference beside each completed box.
References: How self-drilling screws work
Read the product row, including its limits
Manufacturers offer multiple point configurations within screw families. Compare the complete row for the proposed size and point rather than transferring a range from another screw that shares the same general label.
| Record | Where to get it | Question to resolve |
|---|---|---|
| Actual steel thicknesses | Member specification and connection detail | Which layers are penetrated? |
| Exact screw and point | Product designation | Does this specific combination cover the condition? |
| Published drilling range | Current manufacturer table | Are both lower and upper limits satisfied? |
| Unusual material or gap | Project detail and field observation | Does the documentation address this arrangement? |
References: Self-drilling screw product families
Why a larger point is not a general improvement
Treat a proposed point change as a product change. The purchasing goal is not to find the most aggressive-looking tip; it is to match a documented product to the intended work. If a different point is suggested because the specified item is unavailable, record the complete alternative and ask for a comparison before ordering it.
Also separate an installation problem from a selection problem. A screw that struggles to start may have a damaged point, unsuitable tooling, or a mismatch with the material. Simply escalating the point designation conceals which condition changed. Record the observed symptom and the product involved before deciding what the next controlled check should be.
Example: a support changes after the quote
Suppose an estimate was prepared for attachment to one light-gauge support, but an approved revision introduces a thicker connection plate. The original fastener quantity may still be correct while its suitability needs another review. Update the assembly sketch, mark the changed steel layer, and resend that specific item for confirmation.
The useful output is a revised product record linked to the new detail, not a verbal instruction to use a stronger screw. Preserve the old entry as superseded so that purchasing and installation teams can identify why the replacement was selected. Check that any already-delivered boxes are segregated by their approved uses.
- Record both the original and revised detail references.
- Review drilling range and attachment length independently.
- Confirm the accepted product before releasing the revised line.
- Communicate the change to receiving and installation teams.
Common questions
Are point numbers interchangeable between manufacturers?
Do not use the number alone to establish equivalence. Compare the exact screw size, point, listed application, and drilling range in each manufacturer's documentation.
Can I add all assembly layers to find drilling thickness?
Describe every layer, then apply the manufacturer's definition for that product. Steel drilling thickness and total attachment thickness are separate checks, particularly where gaps or insulation occur.
Sources & further reading
Use the current documentation for the exact product and project. Source links do not imply a partnership or endorsement.
- How self-drilling screws work Simpson Strong-Tie
- Self-drilling screw product families ITW Buildex
Prepared with AI assistance. Linked references require current project-specific review. How these guides are prepared.
Products related to this guide
Explore the catalog references and compare the published options with your project documents. Products sharing a guide are not necessarily interchangeable.
- 12-24 x 11/4" with #5 Drill Point
- #14 or 1/4" Fastener Drill Bit
- 12-14 x 1" Stainless with #3 Drill Point
- 12-14 x 1 1/2" Stainless with #3 Drill Point
- 12 x 3 /4" Driller with #3 Drill Point
- 1 /4"-14 x 1 1 /2" with #3 Drill Point
- 12-14 x 2" with #2 Drill Point
- 12-24 x 1 1/4" with #5 Drill Point
- 12-14 x 1 1/2" Driller with Large Washer
- 12-14 x 1" Long Life with #3 Drill Point
- 12-14 x 2" Long Life with #3 Drill Point
- 1/4"-14 x 1 1/4" Driller
- 1/4"-14 x 1 1/4" Long Life Driller
- 1/4"-14 x 1 1/4" Long Life Driller with Large Washer
- 12-14 x 1 1/4" Driller
- 12-14 x 3/4" Driller
- 1/4"-14 x 1" Driller
- 1/4"-14 x 1 1/2" Driller
- 1/4"-14 x 1 1/4" with #3 Drill Point
- 1/4"-14 x 3/4" Driller
- 12-14 x 1 1/2" Long Life Driller
- 12-14 x 1 1/4" Long Life Driller
- 12-14 x 1" Driller
- 12-14 x 1" Driller
- 12-24 x 1 1/4" TEK 4.5
- 12-24 x 1 1/4" TEK 4.5
Prepare a supply inquiry
- Record the project drawing or detail and the specified product, profile, or system.
- List the complete configuration, physical units, quantities, and cuts per piece.
- Request current manufacturer documents; confirm compatibility, price, and availability before ordering.
- Obtain the responsible professional's review for loads, code requirements, or installation.