What size hole do I drill for resin anchors?

The bore diameter should be 2-4mm larger than the stud diameter: M8 = 10mm, M10 = 12mm, M12 = 14mm, M16 = 18mm, M20 = 24mm, M24 = 28mm. The annular gap between stud and bore is filled with resin. Too small a hole won't allow enough resin; too large reduces bond strength and wastes resin.

How deep should I embed resin anchors?

Minimum embedment depth depends on stud size and substrate. Typical minimum depths: M8 = 80mm, M12 = 110mm, M16 = 125mm, M20 = 170mm, M24 = 210mm in solid concrete. Always follow the manufacturer's ETA (European Technical Assessment) for the specific product. In weaker substrates like brick, increase embedment by 50%.

How many fixes per resin cartridge?

A standard 380ml resin cartridge yields approximately 29 fixes for M12 (13ml per fix), 16 fixes for M16 (24ml per fix), or 7 fixes for M20 (55ml per fix). In practice, allow 10-15% waste for purging the nozzle and dead volume. The first few centimetres of each cartridge should be discarded to ensure proper mixing.

How long does resin anchor take to cure?

Cure time depends on temperature and product type. At 20°C: approximately 10-15 minutes for M8-M12, 20-30 minutes for M16-M20, 30-45 minutes for M24. At 5°C, cure times double or more. Below 0°C, most resins won't cure properly. Do not apply load until fully cured. Some products offer fast-cure versions for cold weather use.

Can I use resin anchors in hollow blocks?

Yes, but you must use a perforated sleeve (mesh anchor sleeve) inserted into the hole first. The resin fills the sleeve, which expands into the hollow cores of the block, creating a mechanical and chemical bond. Without a sleeve, the resin simply runs out through the hollow cores. Check the manufacturer's load data for hollow substrates.

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Resin Anchor Calculator — Bore, Embedment & Cartridge Count

Calculate bore diameter, embedment depth, resin cartridge quantity and cure time for chemical anchor fixings.

Stud SizeBore: 14mm, Embedment: 110mm

Number of Fixes

Substrate

Cartridge Size

380ml standard

Cartridge Price

Stud Price

How We Calculate This

This calculator determines the bore size, embedment depth, resin quantity and cure time for chemical resin anchor fixings.

Resin volume

Resin per Fix = Annular Volume = pi x ((Bore/2)² - (Stud/2)²) x Depth
Cartridges = ceil(Total Fixes / Fixes per Cartridge)

Cure time

Cure time varies with temperature. At 20°C = standard time. Below 10°C = double. Below 5°C = quadruple. Do not load before full cure.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.