Schmid RAPID Structural Wood Screws Guide

Schmid RAPID® structural wood screws are designed for engineered timber connections where fixing performance, installation control and reliable technical data matter. TC Fixings stocks two specialist ranges: RAPID® SuperSenkFix for structural timber and CLT, and RAPID® Top-2-Roof for fixing counter battens through on-roof insulation.

This guide explains the role of each range and the main points to check when selecting a screw. It is intended as a practical product overview; the final fixing arrangement must follow the project specification and relevant structural design.

Which Schmid RAPID screw is suitable?

Range	Typical Uses
RAPID® SuperSenkFix	Structural timber framing, CLT walls and floors, corner and wall connections, and suitable steel-to-timber connections.
RAPID® Top-2-Roof	Counter-batten fixing through rigid or compressible insulation into rafters or other supporting timber.

RAPID® SuperSenkFix for timber and CLT

RAPID® SuperSenkFix is a partial-thread structural screw. When correctly positioned, the threaded section engages fully in the receiving timber and draws the head-side component firmly against it.

The SuperSenkFix head is designed to finish cleanly and flush while providing high pull-through resistance. An under-head shoulder also helps the screw centre accurately in suitable pre-drilled steel components.

Structural timber-to-timber connections
CLT wall, floor and corner connections
Side-grain, end-grain and angled connections where covered by the design
Visible connections requiring a controlled flush finish
Suitable steel plates and formed metal components fixed to timber

View RAPID® SuperSenkFix structural screws

RAPID® Top-2-Roof for on-roof insulation

RAPID® Top-2-Roof is a long structural screw developed for on-roof insulation systems. It passes through the counter batten and insulation before anchoring into the supporting timber.

A second threaded section beneath the head holds the counter batten in position. The fixing arrangement is designed to transfer relevant shear and compression forces rather than relying on the insulation to support the batten and roof covering.

On-roof and warm-roof insulation systems
Rigid and non-pressure-resistant insulation
Counter-batten fixing into rafters
Pitched and monopitch roof construction
Specified external wall insulation applications

View RAPID® Top-2-Roof insulation screws

Installation features across the ranges

Both ranges use thread and tip geometry intended to achieve a quick bite with reduced screw-in resistance and reduced splitting. Schmid states that pre-drilling is not normally required for the published applications, subject to the product approval, timber and installation conditions.

Use the correct drive bit in good condition and keep the tool aligned with the specified screw angle. High-powered installation equipment does not replace controlled driving: avoid overdriving the head or damaging the recess.

Specification point: Structural screw selection is not based on length alone. Diameter, thread engagement, head performance, timber density, edge distances, spacing, load direction and corrosion exposure all need to be considered.

Frequently asked questions

Are RAPID® SuperSenkFix screws suitable for CLT?

Yes. Schmid identifies SuperSenkFix for CLT walls, ceilings, side faces and narrow edges, subject to the approved design and installation requirements.

Are Top-2-Roof screws only for rigid insulation?

No. Schmid publishes the range for hard and soft insulation and highlights its suitability for non-pressure-resistant insulation.

Can structural screw quantities be selected on site?

Not for a designed structural connection. Screw number, spacing, angle and embedment should be taken from the project design or checked by a suitably competent person.

Shop Schmid RAPID® structural wood screws

View the stocked range of RAPID® SuperSenkFix and RAPID® Top-2-Roof screws, or contact TC Fixings if you need help matching a specified size.

View Schmid RAPID® structural wood screws | Contact TC Fixings

RAPID® SuperSenkFix for structural timber and CLT

Choosing structural screws for CLT

RAPID® Top-2-Roof for on-roof insulation

Technical note: Always use the current manufacturer documentation, applicable ETA/DoP and project design. This article does not provide a structural fixing schedule.