How to Choose the Right Anchor: Concrete, Brick, Hollow Block & Stone
Most failed fixings on site are not bad products – they are the wrong product for the wall. This guide helps contractors, site engineers and purchase teams pick the right anchor in three questions: what is the base material, how heavy is the load, and how soon must it carry load.
Step 1: Identify the base material
| Base material | Good choices | Avoid |
|---|---|---|
| Solid concrete (slabs, columns, RCC walls) | Bolt / wedge anchors, drop-in anchors, chemical anchors | Nylon plugs for heavy loads |
| Cracked concrete (tension zones, slab soffits) | Anchors approved for cracked concrete, epoxy chemical anchors | Anchors approved only for non-cracked concrete |
| Solid brick | Chemical anchor, frame anchors, DuoPower plugs | Expansion anchors close to edges |
| Hollow block, perforated brick | Chemical anchor with mesh sleeve, DuoPower | Wedge / bolt anchors |
| Natural stone | Chemical anchor, stainless steel cladding clamps | High-expansion anchors that can crack stone |
Step 2: Match the anchor to the load
- Light loads (frames, shelves, light fittings): nylon plugs such as Fischer DuoPower or S plugs.
- Medium loads (railings, brackets, MEP supports): hybrid chemical anchors such as Fischer FIS V Plus or Hilti HIT-HY 200, or steel bolt anchors in concrete.
- Heavy and structural loads (steel structures, rebar connections): epoxy chemical anchors such as Hilti HIT-RE 500 V4 or Fischer FIS EM Plus, designed by an engineer.
- Overhead services (pipes, ducts, cable trays): drop-in anchors such as Hilti HKV or Fischer EA-N with threaded rod.
Step 3: Decide how fast it must carry load
Mechanical anchors (bolt, wedge, drop-in) can be loaded immediately. Chemical anchors need curing time, which grows in cold weather – plan the work so rods are not loaded early.
Step 4: Think about the environment
- Indoors, dry: zinc-plated steel is fine.
- Outdoors, humid or coastal: hot-dip galvanised, stainless steel or Corroshield coated fasteners.
- Seismic zones and safety-critical fixings: use anchors with seismic approval and ask for the documents.
Quick reference
| Job | Typical choice |
|---|---|
| Railing on RCC balcony | Chemical anchor or bolt anchor |
| Pipe hangers from slab | Drop-in anchor + threaded rod + clevis hanger |
| Bracket on hollow block wall | Chemical anchor with mesh sleeve |
| Door / window frame | Frame anchor (Hilti HRD) |
| New column bars into old slab | Epoxy chemical anchor – see rebar anchoring guide |
| Granite or marble facade | Stainless steel cladding clamps – see cladding clamp guide |
Frequently asked questions
Which anchor is best for hollow block walls?
A chemical anchor injected through a mesh (sieve) sleeve, or a universal plug such as Fischer DuoPower for light loads. Expansion anchors do not hold well in hollow block.
Chemical anchor or bolt anchor – which is stronger?
Both can be strong in good concrete. Chemical anchors work better near edges, in brick and block, and for rebar, while bolt anchors carry load immediately.
Can you test an anchor on site?
Yes. A pull-out test checks the installed anchor against the design load. See our pull-out test guide.
Need help choosing?
Send your drawing or a site photo and we will suggest the product and quantity. Delhi +91 90057 00569 · Guwahati +91 90906 76969 · Dubai +971 58 546 4012. Browse Hilti and Fischer anchors.