I’ve checked the current EOTA material so the SEO article can use accurate terminology and current references. In particular, EOTA’s current EAD list includes dedicated assessment documents for mechanical fasteners, bonded fasteners, concrete screws and other fixing systems. EOTA+1

ETA Approved Fixings: A Practical Guide for Installers

When installing fixings and fasteners on a construction project, getting the right product is only half the job. The fixing also needs to be installed correctly and within the conditions for which it has been assessed.

This is where European Technical Assessments (ETAs) become important.

For installers, an ETA provides valuable technical information about where a fixing can be used, the substrates it has been assessed for and the installation conditions required to achieve its stated performance.

Whether you're working with concrete anchors, concrete screws, bonded anchors or other fastening systems, understanding the information behind an ETA can help you avoid common installation errors and ensure the product is being used as specified.

What is an ETA for a fixing?

A European Technical Assessment (ETA) is a technical assessment of the performance of a construction product for defined intended uses.

For fixing products, an ETA can provide information about characteristics such as load-bearing performance, approved substrates, installation parameters, durability and other relevant properties.

EOTA maintains a database of European Assessment Documents (EADs) and ETAs. Its current EAD list includes specific assessment documents covering products such as mechanical fasteners for concrete, bonded fasteners, concrete screws and fasteners for masonry. EOTA

For installers, the important point is that an ETA relates to a specific product and defined conditions of use.

It isn't simply a statement that a particular type of anchor is suitable for every application.

Why are ETA approved fixings important for installers?

A fixing's performance can depend on much more than its diameter and length.

The substrate, embedment depth, hole diameter, installation method, edge distance and spacing can all be important.

For example, EOTA's current assessment documents include specific requirements for mechanical fasteners used in concrete. EOTA

This means that installers should not rely solely on a fixing's appearance or a general load figure.

Instead, the product should be installed according to its technical documentation and manufacturer's instructions.

What should you check before installing an ETA fixing?

Before drilling the first hole, take a few minutes to check the installation requirements.


1. Check the product

Make sure you have the correct:

  • Manufacturer

  • Product type

  • Diameter

  • Length

  • Material or finish

  • Product version

  • Batch or product identification, where required

Two anchors can look very similar but have different technical characteristics and installation requirements.

If the product specified on the drawings is unavailable, don't automatically substitute another fixing simply because it has the same diameter.

The alternative should be checked and approved through the appropriate technical process.


2. Check the substrate

The fixing must be suitable for the material into which it is being installed.

Depending on the product, the approved substrate may include specific types or classes of concrete, masonry or other construction materials.

The distinction can be important.

For example, a mechanical fastener assessed for use in concrete should not automatically be treated as suitable for brick or blockwork.

EOTA's EAD system includes separate assessment documents for different fixing applications, including mechanical fasteners in concrete and screw anchors for masonry. EOTA

Always check the actual substrate against the product documentation.


3. Check the embedment depth

Correct embedment is critical for many anchors.

The manufacturer's documentation may specify a minimum or particular effective anchorage depth.

Installing an anchor too shallow can affect its performance.

Equally, drilling deeper is not necessarily an acceptable solution. The installation must remain within the conditions specified for that product.

Before drilling, confirm the required:

  • Hole depth

  • Embedment depth

  • Fixture thickness

  • Total fixing length


4. Use the correct drill diameter

The drill diameter specified by the manufacturer should be followed.

This is particularly important for mechanical expansion anchors and screw anchors, where the relationship between the fixing and drilled hole contributes directly to installation performance.

Using an incorrect drill bit can result in an installation that does not correspond to the assessed system.


5. Check edge distances and spacing

The position of a fixing can be just as important as the fixing itself.

Minimum edge distances and spacing requirements may apply, particularly for anchors installed in concrete.

Before drilling, check the distance between:

  • The fixing and the concrete edge

  • Adjacent fixings

  • The fixing and openings

  • The fixing and other structural elements

If the specified location cannot be used, don't simply move the fixing to a more convenient position.

Obtain the necessary technical approval before changing the installation.


Hole cleaning: a small step that matters

For many fixing systems, hole cleaning is an essential part of the installation process.

This is especially important with bonded or chemical anchors, where the condition of the drilled hole can affect the interaction between the bonding material and the substrate.

The manufacturer's instructions may specify a particular sequence of drilling, brushing and blowing.

The procedure can vary between products.

So rather than assuming that all chemical anchors are installed in the same way, check the instructions for the exact product being used.


Installation torque for mechanical anchors

Where a fixing requires a specified installation torque, that value should be treated as an installation requirement — not simply a recommendation.

Under-torquing and over-torquing can both create problems.

Installers should use suitable equipment and follow the manufacturer's specified procedure.

Where project requirements call for verification or recording of torque, appropriate calibrated equipment and records should be used.


Chemical anchors: don't forget curing time

Bonded anchors have an additional consideration that mechanical fixings do not: curing time.

The required curing time can depend on factors such as:

  • Product type

  • Temperature

  • Base material

  • Installation conditions

Loading the anchor before the required curing period has elapsed can compromise the installation.

Always check the manufacturer's current installation instructions for the specific product and site temperature.


What if you hit reinforcement?

Finding reinforcement while drilling is a common challenge when installing anchors in concrete.

The solution should depend on the specific project and fixing system.

Installers should not automatically cut or damage reinforcement to continue drilling.

If the specified fixing location cannot be used, the appropriate engineer, designer or technical department should be consulted before changing the installation.


Can an ETA fixing be used anywhere in concrete?

No.

This is one of the most important points for installers to understand.

An ETA relates to a particular product, its assessed characteristics and its defined conditions of use.

For example, EOTA currently lists an EAD specifically covering mechanical fasteners for use in concrete, and individual ETAs identify the product, manufacturer, assessment basis and other technical information. EOTA+1

So seeing an ETA number on a product does not mean that the fixing is automatically suitable for every concrete application.

The installer still needs to check the technical requirements.


What does the ETA tell you on site?

Depending on the product, the ETA and associated documentation can help you establish:

  • Which substrates are permitted

  • Which fixing sizes are covered

  • Required embedment

  • Hole diameter

  • Hole depth

  • Minimum member thickness

  • Edge distances

  • Spacing

  • Installation torque

  • Installation method

  • Environmental conditions

  • Durability characteristics

  • Fire performance, where assessed

  • Seismic performance, where assessed

The exact information will vary between products.

For example, EOTA's current database contains ETAs for individual mechanical fasteners in concrete, including products assessed against EAD 330232-02-0601. EOTA+1


Don't confuse an ETA with an installation instruction

An ETA and installation instructions serve different purposes.

The ETA provides the technical basis for the assessed product and its intended use.

The manufacturer's installation instructions provide the practical information needed to install that particular product correctly.

For installers, both are important.

If the manufacturer's instructions specify a particular drill diameter, hole-cleaning method, setting procedure or torque, those requirements should be followed.


What happens if site conditions are different?

Construction sites rarely go exactly according to plan.

You may discover:

  • A different substrate from that shown on the drawings

  • Insufficient concrete thickness

  • Reinforcement in the drilling location

  • An obstruction

  • An unsuitable edge distance

  • A different temperature

  • A damaged or unsuitable fixing

  • A shortage of the specified product

The safest approach is not to improvise.

If the actual conditions fall outside the documented installation requirements, stop and seek technical clarification.

A different fixing or location may be suitable, but that needs to be established rather than assumed.


ETA fixing checklist for installers

Before installing an ETA-assessed fixing, ask:

Product

  • Is this the specified fixing?

  • Is the diameter and length correct?

  • Can the product be positively identified?

Substrate

  • Is the base material suitable?

  • Does the documentation cover this substrate?

  • Are there cracks, voids or other conditions that need consideration?

Position

  • Is the fixing in the specified location?

  • Are minimum edge distances available?

  • Is the required spacing available?

  • Is reinforcement likely to interfere?

Installation

  • Is the drill diameter correct?

  • Is the hole depth correct?

  • Has the hole been cleaned correctly?

  • Is the correct installation tool being used?

  • Is the specified torque being applied?

  • For bonded anchors, has the required curing time been observed?

Documentation

  • Do you have the current installation instructions?

  • Does the ETA cover the product and application?

  • Has any deviation from the specified installation been approved?


Why following the installation procedure matters

An ETA establishes assessed performance under defined conditions.

The installer plays an important role in ensuring those conditions are actually achieved on site.

A correctly specified fixing that is incorrectly installed cannot be expected to perform in the same way as a correctly installed system.

That is why details such as hole diameter, embedment, cleaning, torque and curing time should never be treated as minor technicalities.

Installation is part of fixing performance.


Final thoughts

ETA approved fixings can provide installers with valuable technical information, but the presence of an ETA does not remove the need to follow the manufacturer's installation instructions.

The key is to understand what has actually been assessed and make sure the installation matches those conditions.

Before drilling, check the product, substrate, position and installation requirements.

And if the conditions on site don't match the documentation, don't guess.

Stop. Check. Confirm. Then install.

For installers, that simple approach can help prevent avoidable mistakes and ensure that fixings are used as intended.