Frequently asked questions

Fiberglass rebar, or GFRP reinforcement, is composite reinforcement for concrete made of glass fiber and a polymer binder. It is produced as bars, meshes and ready-made elements. Fiberglass Estonia sells GFRP reinforcement in both retail and wholesale quantities.

Fiberglass rebar differs from steel in weight, corrosion behaviour, stiffness, thermal and electrical conductivity, and in its design properties. FGE highlights low weight, easier transport and corrosion resistance as the main advantages. Because the material properties differ, the reinforcement must be selected on the basis of structural calculations, not merely by matching bar diameters.

Where the design allows, GFRP reinforcement is used in concrete floors, yards and hardstandings, foundations, terraces and other concrete structures. For these, FGE offers bars, meshes, L-bars and stirrups. Use in a load-bearing or otherwise critical structure must be confirmed with the structural engineer in advance.

Fiberglass rebar does not rust the way steel reinforcement does, because it contains no corroding steel bar. FGE describes its GFRP products as corrosion resistant and suitable for damp or chemically more aggressive environments as well. Even so, the ambient temperature, chemicals, the concrete itself and the intended service life must be taken into account in the design.

According to FGE, GFRP reinforcement can be up to nine times lighter than steel. The lower weight makes handling easier and can reduce the need for on-site transport and lifting. The actual total weight depends on the chosen diameter, mesh size, length and quantity.

GFRP reinforcement is not an electrical conductor the way steel is. This can be useful in structures where the electrical conductivity or electromagnetic effect of metal reinforcement is undesirable. For the same reason, GFRP reinforcement cannot be used as an earthing conductor, and earthing must be solved separately according to the design.

Fiberglass rebar is not automatically suitable for every load-bearing structure. Stiffness, behaviour under temperature, anchorage, deflection and failure mode differ from steel and require calculations made specifically for GFRP. Suitability and detailing must be confirmed by a qualified structural engineer.

Ask for the product data sheet, a test or technical report, and the performance data required by the design. The FGE technical information page holds the documents for the Hard and HardPlus products, and the product pages list dimensions and packaging. ISO 10406-1 describes test methods for FRP bars, but the suitability of a specific product must be verified against its own documents and the design.

Rebar is a single bar or coil used to reinforce lines, edges and joints, while reinforcement mesh is reinforcement already tied into a grid for covering a larger area evenly. Fiberglass Estonia offers both in GFRP: bars and coils, and HardPlus mesh in rolls and sheets. Which one to use comes from the design, and often both are used on the same site.

A bar is usually chosen for linear and edge reinforcement, and a mesh for reinforcing a larger area evenly. The exact solution depends on the loads, the shape of the structure, crack control and the reinforcement layout given in the design. FGE supplies rebar in coils and in straight bars, and mesh in rolls and in sheets.

HardPlus is FGE’s GFRP reinforcement range whose bars have a quartz-sand profile that bonds with concrete. The range includes coils in various diameters and six-metre straight bars. The right diameter and packaging are chosen according to the design and the quantity needed.

HardPlus mesh is sold both in rolls and in sheets. On the FGE product page, the 3 mm and 4 mm meshes come as 57.5 m² rolls, and the thicker versions as 1.2 by 3 metre sheets. Before ordering, check the diameter, the mesh size, the sheet or roll size and the quantity required by the design.

A GFRP L-bar is used, according to the design, as a connecting or anchoring element at corners and where reinforcement runs in different directions. FGE’s standard HardPlus L-bar measures 380 by 380 millimetres and is available in several diameters. Larger diameters can be ordered as a special order when needed.

A GFRP stirrup is a pre-shaped element that holds the longitudinal bars in the position required by the design and helps form a three-dimensional reinforcement cage. FGE offers HardPlus stirrups as a concertina of ten loops, with the spacing chosen according to the design. The manufacturer names the L-block of a slab foundation as one place where they are used.

Fiberglass Estonia offers EPS products for different load levels, for insulating concrete floors and other structures. The website lists EPS 80, EPS 100 and EPS 200 in various thicknesses and board sizes as examples. The right compressive strength, thickness and installation layer must be chosen according to the structure and the thermal calculation.

An EPS L-block is an element made for forming the edge of an insulated slab foundation of a small house. The FGE L-block is a monolithic EPS 200 product in which both the vertical and the horizontal part have 95 millimetres of insulation. The right block height, edge shape and load capacity must be confirmed in the foundation design.

The diameter and mesh size of GFRP reinforcement are chosen on the basis of calculations covering loads, spans, support conditions, crack control and the service environment. The FGE tables help compare the available products and the equivalents stated by the manufacturer. The final choice must come from the structural design or be agreed with the engineer.

The cheapest solution is not decided by the price per metre or per square metre alone, but by the total cost: material, transport, lifting, cutting and installation together. According to FGE, fiberglass rebar is up to nine times lighter than steel, which often removes the cost of a heavy truck and a crane. The FGE calculator compares the quantity, weight and estimated cost of composite and steel reinforcement, so you can see the difference for your own quantity.

Steel rebar must not be replaced with a GFRP bar of the same diameter without calculations. The equivalence tables on the FGE product pages are product-specific background information, but the stiffness and other design properties of GFRP and steel differ. Any such change must be checked and documented by the structural engineer.

In a load-bearing or otherwise critical concrete structure, GFRP reinforcement must be specified in the structural design. The design has to state the material properties, diameters, spacings, lap lengths, anchorages, concrete cover and the other necessary details. For a small non-load-bearing job, ask at least the manufacturer and a qualified specialist for instructions.

A cured GFRP bar should not be bent on site, hot or cold, the way a steel bar is. For corners and cages, factory-made L-bars and stirrups specified in the design are used instead. Bending it incorrectly can damage the composite and reduce its design properties.

GFRP reinforcement is cut with a tool suited to composites and according to the manufacturer’s working instructions. The FGE installation page shows separate comparisons of cutting bars and mesh against steel reinforcement. Use eye, respiratory and skin protection when cutting, and avoid fraying or crushing the bar.

The lap length of GFRP reinforcement must come from the structural design. It is affected by the properties of the bar, its diameter, the strength of the concrete, the bond surface, the stress state and the location of the joint. The lap length normally used for steel reinforcement must not be carried over to GFRP without checking.

The thickness of the concrete cover must follow the design and the service environment of the structure. Although GFRP does not rust like steel, the cover is also affected by bond, fire resistance, construction tolerances and surface wear. Rebar chairs matching the design are used to keep the reinforcement at the right height.

GFRP reinforcement is fixed before concreting so that the bars, meshes and ready-made elements keep the position required by the design while the concrete is poured. The fixings, chairs and tying intervals are chosen according to the structure and the manufacturer’s instructions. Before pouring, the laps, cover, openings and penetrations are checked as well.

GFRP reinforcement must be transported and stored so that the bars, mesh junctions and surface profile cannot be crushed or cut. Coils are opened under control, and the products are kept clean and protected from excessive weather according to the manufacturer’s instructions. Damaged pieces are removed before installation and the package markings are checked.

The quantity is calculated from the bar lengths, mesh area, spacings, laps, L-bars, stirrups and cutting allowance given in the design. For mesh, the area to be reinforced is converted into rolls or sheets and the overlap at the joints is added. Send FGE the drawings or dimensions if you would like help checking the quantity and packaging.

The FGE calculator compares the quantity, weight and estimated cost of the selected composite and steel reinforcement. The mesh calculator also takes square metres and the possible saving on installation or transport into account. The result is an indicative comparison and does not replace structural calculations or a personal quotation.

The price of fiberglass rebar depends on the product, diameter, length, packaging, quantity and delivery. The FGE online shop shows the current prices of the products on offer, and a separate quotation can be requested for a larger or more complex order. When comparing, count transport, lifting, cutting and installation in addition to the material.

Fiberglass Estonia products can be ordered from the FGE online shop, through a price enquiry, or from the company’s resellers. The resellers page lists builders’ merchants and partners in different regions of Estonia. It is worth checking the stock and delivery time of a specific size before travelling or ordering.

Yes, Fiberglass Estonia sells GFRP reinforcement both retail and wholesale. For a larger site, add the design, products, dimensions, quantities, the delivery time you need and the delivery address to your enquiry. On that basis the company can put together a suitable packaging and logistics solution.

Include the chosen product, the type of packaging, the diameter or mesh size, the quantity in metres or square metres, and the delivery address. State the company name, the deadline you need and any special conditions of the project or the site. If the dimensions are not final yet, attach a drawing and ask us to check the selection before you order.

Rebar and reinforcement mesh can be bought from Fiberglass Estonia in the online shop, through a price enquiry, or from the resellers. The resellers page lists builders’ merchants and partners in different regions of Estonia, so the goods are available outside Tallinn as well. It is worth asking about the stock and delivery time of the exact size before travelling or ordering.

The price of reinforcement mesh depends on the diameter, mesh size, roll or sheet size and the quantity ordered. The current prices of the meshes on offer are shown in the FGE online shop, and a separate quotation can be requested for a larger quantity. When comparing, count transport and installation in addition to the material, as lightweight mesh needs no lifting equipment.

The amount per square metre comes from the design: it depends on the bar spacing, diameter, number of layers and laps. For mesh, the area to be reinforced is converted into rolls or sheets and the overlap is added; for bars, the running metres are calculated from the spacing. Use the FGE calculator or send us a drawing and we will help you check the quantity.

The delivery time depends on the product, the quantity and whether the goods are in stock or on order. Products in the online shop are usually available faster than special-order sizes, L-bars and large site quantities. If you have a fixed deadline, write or call before ordering and we will confirm the stock and delivery time right away.