Galvanised slab nails for securing insulation boards to timber. Available in sizes from 100mm to 200mm, conforming to Eurocode 5 service class 2 for medium duty rust protection. Sold by the kilogram or in 10kg cartons.
Size
Weight
Pack Type
Price
QTY
100 x 3.75mm
10kg
Carton
£28.65£34.38
125 x 3.75mm
10kg
Carton
£28.65£34.38
150 x 3.75mm
10kg
Carton
£28.65£34.38
180 x 4.50mm
10kg
Carton
£28.65£34.38
200 x 4.50mm
10kg
Carton
£29.85£35.82
150 x 3.75mm
1kg
TIMbag
£3.24£3.89
180 x 4.50mm
1kg
TIMbag
£3.24£3.89
200 x 4.50mm
1kg
TIMbag
£3.24£3.89
Galvanised slab nails are the standard fixing for attaching rigid insulation boards to timber framing, battens, and studwork. They have a large flat head to grip the face of the board without punching through, and a shank length that gives enough bite into the substrate behind. Available here in five sizes from 100 x 3.75mm up to 200 x 4.50mm, so you can match the nail to the insulation thickness you’re working with rather than just hammering the longest thing in the box and hoping for the best.
The galvanised coating provides medium duty rust protection, which makes these appropriate for interior and sheltered applications where the timber is not in direct ground contact or permanent wet exposure. These nails conform to Eurocode 5 and are rated for service class 2, meaning they are suited to timber in conditions where moisture content may occasionally be elevated but doesn’t stay that way. Roof spaces, wall cavities, and internal insulated frames are all typical environments.
Where Galvanised Slab Nails Are Used
The large head is the key feature here. Standard round wire nails don’t have the bearing area to hold a lightweight insulation board in place, especially during the build-up phase before outer cladding or plasterboard is fixed. Slab nails spread the load across a wider surface, stopping the head from pulling through the foam or mineral wool face. Fix them by hand with a hammer rather than a nail gun, as overdriving is easy and compresses the board unnecessarily.
Sizing for Common Insulation Thicknesses
As a general guide, the nail shank needs to penetrate the timber substrate by at least 30–40mm after passing through the insulation. For 50mm insulation onto a batten, a 100mm nail gives adequate timber engagement. Step up to 150mm or 180mm when insulation boards are thicker or where you’re pinning through a double layer. The 200 x 4.50mm option suits the heavier board-and-batten assemblies you find on timber frame builds.
Available loose by the kilogram for smaller jobs or in 10kg cartons when you’re fitting out a whole floor or wall run.
Pro Tip: When fixing into softwood studwork, tilt the nail at a slight angle rather than driving it dead straight, as this increases withdrawal resistance and helps hold the board more securely while the outer skin goes on.
Galvanised slab nails are used primarily in timber frame construction, insulated stud wall systems, and roof insulation installations where rigid or semi-rigid boards need to be temporarily or permanently fixed to a timber substrate. Joiners, insulation fixers, and self-build teams use them regularly when installing PIR, EPS, or mineral wool boards to battens and studwork. They are also common in floor insulation work where boards are fixed down before a floating deck or screed goes on top.
Best For
Fixing rigid insulation boards to timber
Timber frame wall and roof insulation
Floor insulation pinning
Interior and sheltered cavity applications
Works With
PIR insulation boards
EPS foam boards
Mineral wool slabs
Softwood battens and studwork
Timber framing
Key Specifications
Sizes: 100 x 3.75mm, 125 x 3.75mm, 150 x 3.75mm, 180 x 4.50mm, 200 x 4.50mm
Galvanised finish for medium duty rust protection
Conforms to Eurocode 5
Service class 2 rated
Available in 1kg and 10kg quantities
Sold in TIMbag or carton pack
Not suitable for: Not suitable for ground contact or permanently wet conditions where hot-dip or A4 stainless fixings would be required. Not intended for use with a nail gun as overdriving can compress insulation and reduce thermal performance.
Galvanised slab nails are driven by hand using a standard claw hammer. Mark out your fixing positions first, spacing them at roughly 300–400mm centres around the perimeter of each board and at any intermediate support points. Hold the nail upright against the board face and drive it in with firm, controlled strikes, stopping as soon as the head sits flush against the surface.
Avoid overdriving. The large flat head is there to distribute load, not to sink below the surface. If the nail head pulls through, the fixing has failed and you will need to reposition rather than try to patch around it. Check that the shank is fully engaging the timber behind, especially on thicker insulation, as a nail that barely catches the substrate will not hold reliably once the board is under any lateral load.
Select the correct nail length based on insulation thickness, ensuring at least 30mm of shank penetrates the timber substrate
Mark fixing positions on the insulation board, spacing at 300 to 400mm centres around the perimeter and at intermediate supports
Position the nail perpendicular or at a slight angle to the board face
Drive with a standard claw hammer using firm, controlled strikes
Stop driving as soon as the head sits flush with the board surface
Check the board is held firmly and that no nail heads have punched through the insulation face
What is the difference between the 3.75mm and 4.50mm shank sizes?
The 3.75mm shank is used on the smaller nail lengths from 100mm to 150mm, where the timber engagement depth is moderate. The 4.50mm shank on the 180mm and 200mm nails provides more withdrawal resistance when the nail is passing through thicker insulation before reaching the substrate, compensating for the longer unsupported length.
Can these nails be used in a nail gun?
No. Slab nails are designed for hand fixing with a hammer. A nail gun drives too fast and with too much force, and you will almost certainly overdrive the head through the insulation face rather than leaving it flush. Hand fixing gives you the control the job requires.
These galvanised slab nails are manufactured with a large flat head profile and a smooth shank, finished with a galvanised coating that provides medium duty corrosion resistance. They conform to Eurocode 5, the European standard for the structural design of timber structures, and are rated for service class 2, covering timber in conditions where moisture content may temporarily exceed 20 percent but returns to normal levels over time.
Sizes Available
100 x 3.75mm, 125 x 3.75mm, 150 x 3.75mm, 180 x 4.50mm, 200 x 4.50mm
Finish
Galvanised
Corrosion Protection
Medium duty
Standard
Eurocode 5
Service Class
2
Pack Options
1kg TIMbag, 10kg Carton
Head Type
Large flat head
Size
100 x 3.75mm, 125 x 3.75mm, 150 x 3.75mm, 180 x 4.50mm, 200 x 4.50mm
Weight
10kg, 1kg
Pack Type
Carton, TIMbag
Reviews
There are no reviews yet.
Be the first to review “Slab Nail – Galvanised”Cancel Reply
Reviews
There are no reviews yet.