DIN 436 Square Washers for Timber Bolts
DIN 436 square washers, M10 to M52 — the wide square plate washer used under hex bolts in timber and general construction — with the full collected 15-size table: bore, width across flats, thickness limits and the source's reference mass per 1000 units.
Last updated: 2026-11
Specifications
DIN 436 is the square washer that goes under a hex bolt head or nut when the bearing surface is soft or oversized: timber frames, sandwich panels, masonry plates and general construction steelwork. The square form covers far more area than a round washer of the same stock, spreading the clamp load so the bolt does not pull into the wood or crush the substrate, and the flat square edges bridge oversized holes. The collected table runs M10 to M52 in the large end of the series — bore d (min = nominal size / max), width across flats s (max = nominal size / min), the h thickness triple (Nominal Size / max / min), and the source's reference mass per 1000 units, the figure bulk timber-hardware purchasers price the line from. For the chamfered bore variant used with washer-faced bolts see DIN 436's sibling specifications; for the taper-washer counterpart that seats on channel and I-section flanges, see DIN 434 on this site. Materials and finishes are not printed by the collected specification and stay per RFQ.
| Standard | DIN 436 — square washers (product grade C), for hex head bolts and nuts |
|---|---|
| Series | M10 – M52 (15 sizes tabulated) |
| Tabulated geometry | Per size: bore d (min=nominal size / max), width across flats s (max=nominal size / min), thickness h (Nominal Size / max / min), reference mass per 1000 units ≈ kg |
| Function | Wide square bearing plate — spreads clamp load on timber and soft substrates, bridges oversized holes |
| Family note | Taper-washer counterpart for U-sections DIN 434; for I-sections DIN 435 |
| Materials / strength | Not tabulated by the collected specification — per RFQ (material and finish per drawing callout) |
| For Nominal Thread Diameter | d — min=nominal size | d — max | s — max=nominal size | s — min | h — Nominal Size | h — max | h — min | per 1000 units ≈ kg |
|---|---|---|---|---|---|---|---|---|
| M10 | 11 | 11.43 | 30 | 28.7 | 3 | 3.6 | 2.4 | 20 |
| M12 | 13.5 | 13.93 | 40 | 38.4 | 4 | 4.6 | 3.4 | 45.7 |
| M16 | 17.5 | 18.2 | 50 | 48.4 | 5 | 6 | 4 | 88.7 |
| M20 | 22 | 22.84 | 60 | 58.1 | 5 | 6 | 4 | 126 |
| M22 | 24 | 24.84 | 70 | 68.1 | 6 | 7 | 5 | 209 |
| M24 | 26 | 26.84 | 80 | 78.1 | 6 | 7 | 5 | 275 |
| M27 | 30 | 30.84 | 90 | 87.8 | 6 | 7 | 5 | 348 |
| M30 | 33 | 34 | 95 | 92.8 | 6 | 7 | 5 | 385 |
| M33 | 36 | 37 | 100 | 97.8 | 6 | 7 | 5 | 423 |
| M36 | 39 | 40 | 110 | 107.8 | 8 | 9.2 | 6.8 | 685 |
| M39 | 42 | 43 | 125 | 122.5 | 8 | 9.2 | 6.8 | 895 |
| M42 | 45 | 46 | 135 | 132.5 | 8 | 9.2 | 6.8 | 1050 |
| M45 | 48 | 49 | 140 | 137.5 | 8 | 9.2 | 6.8 | 1120 |
| M48 | 52 | 53.2 | 150 | 147.5 | 10 | 11.2 | 8.8 | 1600 |
| M52 | 56 | 57.2 | 160 | 157.5 | 10 | 11.2 | 8.8 | 1820 |
Materials
- Material and finish specified per RFQ — the collected specification table covers geometry and reference mass only
Ordering & documentation
Documents
Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.
Quotation
- The fastener family (DIN 436 Square Washers for Timber Bolts) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
- Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
- Quantity per size and your target delivery date.
- Destination country, and any required documents (for example a mill test certificate) so the quote includes them.
Sample & supply
Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.
Storage & shipping
Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.
Frequently asked questions
When does a timber bolt need a square washer instead of a round one?
When the contact face cannot take a point load. Round washers dig into soft timber or thin plate as the joint is tightened; the square washer's larger footprint spreads the same clamp load over more surface, which is why it is the standard companion to coach bolts and hex timber bolts in frame construction. It also covers slotted or oversized holes that a round washer would pull through. Match the washer to the bolt size — the tabulated width across flats grows with the series — and check the substrate: on steel flanges that are sloped, a taper washer is the right part instead.
What is the MOQ and lead time for this washer type?
The minimum order quantity is 10,000 pieces. Stock items ship in 3–7 days; non-stock items are confirmed at quotation. Common sizes are widely stocked; confirm the exact schedule against quantity and size mix at quotation.
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support