Fosroc Lokfix E55
Styrene-free vinylester resin cartridge system for medium-to-heavy-duty anchoring of rebar, threaded rod and fixings into cracked and un-cracked concrete and masonry.
What is it?
A two-component, styrene-free vinylester-resin chemical anchoring grout supplied in 300 ml coaxial cartridges with a static mixer nozzle. It cures rapidly to bond threaded rod, rebar and fixings into drilled holes in concrete and masonry.
Where is it used?
Post-installed reinforcement starter bars, structural steel base plates, facade and cladding brackets, balustrades, machine bases, MEP supports and connections to existing RCC in repair, retrofit and new-build projects.
Why use it?
Delivers high bond strength with ETA and C1 seismic accreditation, works in dry, damp and water-flooded holes, applies no expansive force (allowing close edge distances), and returns to service fast.
How is it applied?
Drill, then clean the hole by blow-brush-blow, inject resin from the base of the hole to three-quarters full, and insert the fixing with a twisting motion within the gel time. Do not load until full cure.
About Fosroc Lokfix E55
Fosroc Lokfix E55 is a chemical anchoring and bonding system built around a styrene-free vinylester resin, supplied as a coaxial 300 ml cartridge that dispenses both components through a static mixer nozzle using an ordinary skeleton gun. The moment the two parts pass through the mixer they react, set and cure to lock threaded rod, anchor bolts, reinforcement bars and a wide range of steel fixings into holes drilled in concrete, stone and masonry. It belongs to Fosroc’s Lokfix family of injectable resin anchors and sits in the middle of the range: heavier-duty than the polyester Lokfix E35 and below the pure-epoxy Lokfix E75. The product is supplied in two installation grades. Lokfix E55S is the standard-temperature grade, optimised for substrate temperatures from -10 to +40 degrees C, and it is the variant that carries C1 seismic resistance and a fire rating of up to two hours. Lokfix E55L is the low-temperature grade for cold substrates from -20 to +15 degrees C, but it does not carry the seismic or fire approvals. For Indian projects, where seismic design is mandatory across most of the country, E55S is the workhorse specification. The system is accredited under European Technical Assessments (ETA-18/0585, ETA-18/0586 and ETA-18/0587) and the corresponding EAD documents for anchoring in cracked and un-cracked concrete, post-installed rebar and masonry. Because it is a bonded anchor rather than an expansion anchor, it applies no bursting force to the substrate, which lets designers place fixings closer to slab and beam edges than mechanical anchors allow, and makes it the preferred choice when drilling near edges, in thin sections or in dense reinforcement. For engineers, consultants, architects and procurement teams in India, Lokfix E55 offers a documented, code-referenceable anchoring solution backed by Fosroc’s free Lokfix design software for load calculation.
The technical insight
The defining technical choice in Lokfix E55 is the vinylester chemistry. Vinylester sits between cheaper polyester (Lokfix E35) and premium epoxy (Lokfix E75) in both performance and price. It cures faster than epoxy and tolerates damp and even water-filled holes far better than polyester, which is why E55 is accredited for dry, damp and flooded concrete. Cure is strongly temperature-dependent and the data sheet quantifies this: for E55S at +20 degrees C the gel time is about 6 minutes and dry curing is around 45 minutes, while at +5 degrees C gel extends to roughly 25 minutes and full cure to about 120 minutes, and in the +35 to +40 degrees C range gel drops to 2 minutes with cure near 20 minutes. Critically, in wet or damp conditions both gel and set times double, a factor often missed on Indian sites during monsoon. Cured mechanicals are high: 100 MPa compressive strength, 15 MPa flexural strength, a 14,000 MPa elastic modulus and Shore D hardness of 90, all tested to EN 196, with a mixed density of 1.77 kg/L. The cured resin holds a permanent service temperature range of -40 to +72 degrees C and tolerates temporary excursions to +120 degrees C. Hole preparation governs real-world capacity more than the resin itself: drill bit diameter is rod diameter +2 mm for threaded rod and +4 mm for rebar, and the hole must be cleaned with the blow-brush-blow cycle (four passes each) until dust-free, because residual dust is the single largest cause of bond failure.
Where it is used
- Post-installed reinforcement (starter bars and dowels) connecting new RCC to existing concrete in extensions and retrofits
- Anchoring structural steel base plates, holding-down bolts and column connections
- Fixing facade, cladding, curtain-wall and stone brackets to concrete and masonry backgrounds
- Securing balustrades, handrails, railings and safety barriers
- Bolting down machine bases, plant, pumps and vibrating equipment
- Anchoring MEP services, cable trays, pipe supports and electrical fixings
- Bonding into solid and hollow masonry and brick using hollow-block sleeves
- Seismic-rated (C1) fastenings where E55S is specified
- Surface crack sealing and general structural bonding applications
Key advantages
- Styrene-free, low-VOC and LEED-compliant formulation with low odour for enclosed and occupied spaces
- High bond strength with ETA accreditation for cracked and un-cracked concrete, rebar and masonry
- C1 seismic resistance and up to 2-hour fire rating (E55S grade) suited to Indian seismic design codes
- Works in dry, damp and water-flooded holes, including submerged and external conditions
- Applies no expansive force, permitting fixings closer to edges and in thin or congested sections
- Rapid return to service, with cure in roughly 20 to 45 minutes at typical Indian site temperatures
- Dispensed with a standard 300 ml skeleton gun, needing no special mixing or pumping equipment
- Re-usable cartridge by simply replacing the static mixer nozzle, reducing waste
- Free Lokfix design software for compliant anchor and rebar load calculation
- Waterproof cured resin that protects the embedded steel from corrosion
Limitations & considerations
- Load and anchor design must be carried out by a qualified engineer using the Lokfix software or ETA documents, not by site rule-of-thumb
- Gel and cure times roughly double in wet or damp holes, slowing installation during monsoon
- Bond capacity is highly sensitive to hole cleaning; inadequate blow-brush-blow cleaning is the main cause of under-performance
- Standard E55S is rated only down to -10 degrees C substrate temperature; below this the low-temperature E55L grade is required
- E55L does not carry C1 seismic or fire approval, so it cannot be used where those are specified
- Cartridges should be conditioned to +15 to +30 degrees C for use and have only a 12-month shelf life
- May stain natural or decorative stone, so trial suitability before use on exposed finishes
- Hollow masonry requires hollow-block sleeves and a separate method statement
- Extension nozzles are needed beyond 190 mm embedment and piston plugs beyond 240 mm depth or holes over 20 mm diameter
Selection & best practice
Always design the anchor with the Fosroc Lokfix software or the relevant ETA, then size the drill bit at rod diameter +2 mm (threaded rod) or +4 mm (rebar). Drill with a percussive drill, then clean rigorously: blow out four times, wire-brush four times, blow out four more times, repeating until no dust remains, and remove any standing water. Condition cartridges to +15 to +30 degrees C, then extrude two or three full squeezes until the resin runs a consistent grey before use. Inject from the back of the hole, pulling back to fill three-quarters with no voids; use an extension nozzle beyond 190 mm depth and a piston plug for overhead or deep holes. Insert the fixing with a gentle twisting motion within the gel time, hold it straight and on depth until set, and do not load or torque it until the full cure time for the substrate temperature has elapsed, doubling that time in damp conditions.
Specifications
| Product type | Two-component styrene-free vinylester resin chemical anchor (cartridge) |
| Grades | E55S (standard, -10 to +40°C); E55L (low temp, -20 to +15°C) |
| Compressive strength (EN 196) | 100 MPa |
| Flexural strength (EN 196) | 15 MPa |
| Elastic (E) modulus (EN 196) | 14,000 MPa |
| Shore D hardness | 90 |
| Mixed density | 1.77 kg/L |
| Gel time at +20°C (E55S, dry) | approx. 6 minutes |
| Dry cure time at +20°C (E55S) | approx. 45 minutes |
| Gel time at +5°C (E55S, dry) | approx. 25 minutes |
| Permanent service temperature | -40 to +72°C |
| Temporary service temperature | -40 to +120°C |
| Threaded rod range | M8 to M30 |
| Rebar / anchor diameter range | Ø8 to Ø32 mm |
| Drill diameter | Rod dia +2 mm (rod); rod dia +4 mm (rebar) |
| Accreditation | ETA-18/0585, ETA-18/0586, ETA-18/0587; C1 seismic, 2-hr fire (E55S) |
| Substrate conditions | Dry, damp and flooded concrete; cracked & un-cracked; masonry |
| Pack size | 300 ml cartridge, boxes of 12, with static mixer nozzle |
| Shelf life / storage | 12 months at +5 to +25°C in a dry warehouse |
| VOC | Low VOC, LEED-compliant, styrene-free |
Industry use cases
Infrastructure & Bridges
Post-installed dowels and starter bars tying new deck slabs, parapets and crash barriers into existing RCC piers and abutments, with seismic-rated E55S for highway and metro structures.
Commercial & High-Rise
Anchoring curtain-wall, ACP cladding and stone-facade brackets to slab edges and shear walls where no-expansion bonding allows close edge distances in thin perimeter sections.
Industrial & Plant
Holding-down bolts and base-plate fixings for machinery, pumps and compressors, where vinylester chemical resistance and vibration tolerance outperform expansion anchors.
Repair & Retrofit
Connecting new columns, jackets and shear walls to existing concrete during strengthening and seismic-retrofit works, using E55’s flooded-hole capability on damp old concrete.
MEP & Building Services
Fixing cable trays, pipe supports, HVAC plant and fire-rated services, drawing on the up-to-2-hour fire rating of the E55S grade in plant rooms and service shafts.
Frequently asked questions
Is Fosroc Lokfix E55 an epoxy or a vinylester anchor?
What is the difference between Lokfix E55S and E55L?
Can Lokfix E55 be used in wet or water-filled holes?
What sizes of rebar and threaded rod can it anchor?
How long before the anchor can be loaded?
Is Lokfix E55 suitable for seismic design in India?
How we position Fosroc Lokfix E55
Within Space Arc’s Fosroc range, Lokfix E55 is the mid-tier chemical anchor: it sits above the styrene-free polyester Lokfix E35 (for lighter fixings) and below the pure-epoxy Lokfix E75 (for the heaviest-duty anchoring and maximum chemical resistance). Choose E55 when you need ETA-accredited, seismic-rated bonding in damp or flooded concrete without paying the epoxy premium. It pairs naturally with Fosroc repair systems such as the Renderoc mortar range and Nitobond bonding agents on retrofit jobs, and with Conbextra cementitious grouts where large base-plate voids must be filled rather than anchored. Against the wider market, the closest competitor products an Indian specifier will weigh up are Sika AnchorFix and Sika injection anchors, Hilti’s HIT-RE and HIT-HY resin systems, and Bostik/Bond It vinylester cartridges; in the Indian repair and waterproofing space, brands like Dr. Fixit (Pidilite), STP and MBS are better known for membranes and admixtures than for ETA-accredited structural anchors, so they are rarely a direct substitute for a seismic-rated bonded anchor. As an authorised Fosroc distributor and applicator across Delhi NCR and Pan-India, Space Arc supplies genuine Lokfix E55 cartridges with batch traceability and can provide method statements and Lokfix design-software support to ensure the specified anchor performs as the ETA intends.
Related Grouts & Anchors products
Source Fosroc Lokfix E55 for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.