Unite sheet-to-sheet overlap screws
Sheet-to-Sheet Overlap Screws for Roofing and Cladding
What our sheet-to-sheet overlap screws are designed to do
Our sheet-to-sheet overlap screws are designed for joining thinner roofing and cladding sheets where the overlap itself needs to be pulled together cleanly and securely. This product family covers the core overlap range for standard sheet joints, plus fixed-flange versions for specific roof build-ups.
The key selection points are sheet thickness build-up, head style, corrosion requirement, drill capacity and clamp length. This range is also built around overlap-screw geometry with reduced drill point, low thread pitch and free space between thread and head, so the sheets can be clamped together correctly during installation.
Choose the right sheet-to-sheet overlap screw
Hexagon-head overlap screws
Choose our hexagon-head overlap screws when you need a direct solution for overlapping thinner roofing and cladding sheets. This is the core overlap range, with multiple dimensions and both standard and stainless variants to help match the joint build-up and project environment.
See details, sizes and tables for our hexagon-head overlap screws on page 26 in the catalogue
Pan head overlap screws
Choose our pan head overlap screws when the overlap detail calls for a pan head instead of a hexagon head. They stay within the same sheet-to-sheet overlap family while giving you a different head format for the joint detail and installation method.
See technical details for our pan head overlap screws on page 26 in the catalogue
Flange-head overlap screws
Choose our flange-head overlap screws when you are overlapping insulated, load-bearing roofing sheet and the joint calls for a fixed 14 mm flange. This subgroup is the right fit when the roof build-up differs from the thinner-sheet overlaps covered in the standard stitching range.
See details and tables for our flange-head overlap screws on page 27 in the catalogue
Detailed sheet-to-sheet overlap screw data in our catalogue
The catalogue below is where you can compare the exact designations in our sheet-to-sheet overlap screw range. It helps you review head style, drill capacity, clamp length and the available standard or stainless options before you choose a screw for the actual overlap detail.
Use these pages to separate the standard overlap range from the fixed-flange overlap screws used for insulated, load-bearing roofing sheet, and to check that the screw geometry matches the sheet build-up you are working with.
Get help choosing the right overlap screw
We help contractors, roofing and cladding teams, and technical buyers choose the right overlap screw before installation issues show up on site. If you need help matching sheet build-up, head style, corrosion requirement or clamp length, we can point you to the right option quickly.
How do I choose between standard overlap screws and flange-head overlap screws?
Choose the standard overlap screws when you are joining thinner roofing and cladding sheets. Choose the flange-head versions when the overlap belongs to insulated, load-bearing roofing sheet and the detail calls for the fixed 14 mm flange shown in that subgroup. The joint build-up, not just the screw diameter, is what decides which part of the range you should work from.
When is a stainless overlap screw the better choice?
Stainless overlap screws are the better choice when the project environment or specification calls for a more corrosion-resistant fastening than the standard carbon steel options. That matters most on exposed roofing and cladding where the screw choice needs to match the expected environment over time, not just the immediate installation detail.
Why does the free space between thread and head matter on an overlap screw?
It matters because the overlap screw is designed to pull the sheets together in that free space during installation. If that geometry is wrong for the build-up, the lower sheet can loosen or the sheets may fail to clamp together properly, which can leave the joint misaligned and reduce performance with respect to hole edge failure.
What should I check before choosing drill capacity and clamp length?
Start with the real sheet build-up in the overlap and the substrate thickness the point must drill through. Drill capacity must suit the material thickness, and clamp length must suit the joint so the sheets can be drawn together correctly. That is why the catalogue tables should be matched to the actual detail, not just the nominal screw size.
Do sheet-to-sheet overlap screws need to be tightened to spin?
Yes. Our catalogue states that overlap screws should always be tightened to spin. That installation method is part of how the sheets are brought together correctly, so treating them like a general sheet-fastening screw can leave the overlap short of full clamping.
Can Unite help us choose the right overlap screw for our roof or cladding detail?
Yes. We help teams compare the joint build-up, corrosion demand, head style and drilling requirement before the order is placed. That is often the fastest way to avoid site delays, rework or a screw that fits on paper but not in the real overlap detail.