The fixing guide from TOX
In this comprehensive guide, you will find practical information and valuable tips on our innovative fixing solutions. In the following, we explain the basic principles of fixings and what you need to consider for successful and secure installations.
Whether you’re a DIY enthusiast or a professional tradesperson, this guide will help you learn more about our various types of fixing solutions, their functions and applications, as well as the building materials they are designed for. Our guide assists you in finding the right anchor for your fixing project within our extensive range, identifying the substrate if unknown, and creating optimal drill holes. Additionally, we provide tips and tricks for common applications.
With the TOX Fixing Guide, you will gain a fundamental understanding of fixing technology.
Also useful: our fixing clips also explain clearly and comprehensibly how a plug is used in practice.
You can find all videos on our YouTube channel at www.youtube.com/toxgermany.
The right choice of fixing depends on the specific building material and the load to be mounted.
The following points should be considered:
- Which building material was used?
- How to drill correctly?
- Where does the correct installation take place?
- How does a plug work?
The following chapters will help you answer these questions.
The basics of fixing
A plug is a component used in fastening technology for materials where a screw cannot be directly inserted. In a screw anchor, the connection is made using a screw, whereas a wooden dowel, similar to a nail, forms the connection itself.
Before the use of the first screw anchors, holes were either left during wall construction or later chiseled out. A wooden piece was then embedded in these holes using plaster or mortar, allowing a screw to be inserted afterward.An alternative method involved hammering a split wooden piece into a drilled hole. When a screw was inserted, the wood expanded and was additionally compressed, securing the fixing.
The first industrially manufactured expansion plug was produced in England in 1910. This plug consisted of a hemp cord and a type of adhesive made from animal blood.
In Germany, the first industrially manufactured expansion plug with pressed hemp cord was delivered in 1926.
Today’s wall plugs are made of plastic or metal or both. They are available in many different designs for a wide variety of walls, ceilings and floors.
Building materials
The type and condition of the substrate are decisive factors for the correct choice of fixing system.
The most commonly used building materials are:
Concrete: An artificial stone made from cement, aggregate (gravel, sand), and mixing water.
Solid brick (with a dense structure) / masonry brick / clinker: A composite material made of bricks and mortar. The bricks used typically have no cavities and feature high compressive strength. Their perforation ratio is less than 15%.
Solid sand-lime brick: An artificially manufactured brick made from a lime-sand-water mixture. Solid sand-lime bricks have high compressive strength and are suitable for both interior and exterior walls.
Aerated concrete (solid brick with a porous structure): Aerated concrete (solid brick with a porous structure): Have a low compressive strength and numerous pores. For optimal fixing, it is best to use special plugs such as the Ytox aerated concrete plug or the Apollo and Tetrafix XL frame plugs.
Perforated brick with a dense structure: Made from the same high-compressive-strength material as solid bricks with a dense structure but contain cavities.
Perforated brick with a porous structure (Poroton): Due to their cavities and pores, these bricks have low compressive strength, requiring careful anchor selection. Suitable options include plugs like Fassad and Bizeps or fixings such as the Liquix injection system.
Wall panels, gypsum plasterboard, gypsum fibreboards: Thin-walled boards with low strength. Cavity fixings are used here, which form a positive connection behind the board. For light fixings and a maximum board thickness of 12.5 mm, the Spiral plasterboard plug can be used. For higher loads and a panel thickness of up to 30 mm, the Acrobat should be used.
Insulation boards (polystyrene boards, rigid polyurethane foam boards, etc.): Feature low compressive strength and numerous pores. Insulation plugs like Thermo and Thermo Plus, with their large external thread, are ideal for light fixings in these materials.
Unknown building material: If your building material is not one of those listed, e.g. clay, please contact our technical hotline.
Note:
Non-load-bearing layers such as plaster or wall cladding must not be used as an anchoring base and should be considered when selecting the anchor (e.g., anchor length).
Determining the substrate
In a shell construction, the building materials are still easy to recognise. However, as soon as the wall is plastered, it is almost impossible to recognise the building material with the naked eye. In this case, a test drilling at the edge with a small drill diameter helps to recognise what is hidden beneath the surface.
Concrete: Produces a very fine, white to gray drill dust.
Solid brick (masonry brickwork): Produces the unmistakable red drill dust.
Aerated concrete: Produces light grey, coarse-grained drill dust.
Perforated brick: Noticeable cavities while drilling; dust is light red/orange.
Gypsum plasterboard: Cavity behind the panels; dust is white and fine.
Sand-lime brick: Dust is white and fine-grained, almost sandy.
If a test drilling is not desired or possible, an all-purpose plug can be used instead. We recommend our red TRI all-purpose plug.
Positioning of drill holes
To ensure that the anchor securely holds the applied loads without breaking or cracking, it must be installed at sufficient distances from building material edges (edge distances) and at proper spacing between multiple fixings (axial distances). For steel and chemical anchors, these distances are typically specified in the respective approvals.
If the anchor does not hold, it may be due to the following reasons:
Fracture of the anchoring base
Causes: Excessive loads, low strength of the building material, incorrect anchor selection, or insufficient axial or edge distances.
Cracking of the component
Causes: Insufficient component dimensions or failure to maintain the required axial or edge distances.
Pulling out of the anchor
Causes: Failure of friction or form locking due to excessive load or incorrect installation (e.g., drill hole too large or unevenly drilled).
Steel fracture
Causes: The screw strength is insufficient for the suspended load.
Choosing the right drill bit
To achieve optimal holding values, drill bits with the certification mark of the Masonry Drill Bit Certification Board 
should be used.
Additionally, the drill hole must be thoroughly cleaned after drilling. The following drilling methods are used for various building materials:
Rotary drilling: Material is removed through rotation and a spiral cutting edge without damaging the building material. Drilling should be done with a standard drill and without impact in aerated concrete, perforated brick, and wall panels to prevent building material webs from breaking and to avoid oversized drill holes. Suitable for: Panel materials, porous building materials (e.g., aerated or pumice concrete), and perforated bricks.
Impact drilling: Material is shattered by impact and transported out of the drill hole with the helix. Drilling with an impact drill using light blows for substrates made of solid stone with a dense structure (solid brick or solid sand-lime brick) and rather soft materials. The drill is propelled forwards by many light blows from the machine.
Hammer drilling: The hammer drill works with fewer but significantly more powerful blows. The hammer mechanism does the main work. Drilling with a hammer drill with hard blows and high drilling progress, for drill holes that require high drilling quality. Suitable for solid stone substrates with a dense structure, e.g. for concrete or natural stone, etc.
Hearing protection
When working with power tools, noise levels can still be high despite the prescribed maximum noise limits. Therefore, suitable hearing protection is essential for regular use of these devices.
There are three types of workplace noise protection:
- Earplugs
- Earmuffs (headphone-like hearing protection)
- Otoplastics (custom-made hearing protection plugs made of acrylic or silicone)
Drill hole cleaning
Optimal drill hole cleaning is an important factor for fixings, as drill dust in the building material can reduce the holding values of an anchor by more than 50%.
Drilling dust acts as a slip layer for friction-based anchors, such as the Barracuda expansion plug, causing them to slip out of the hole. For bonded anchors, like Liquix injection mortar, drilling dust functions as a separating layer, preventing a strong bond between the mortar and the anchoring base. To ensure a secure fixing, especially for products with official approvals, drill hole cleaning is mandatory as specified in the respective approval.
Optimal cleaning:
The best drill hole cleaning method combines multiple blow-outs and brushing, for example, using the Taifun blow-out pump and the Brush cleaning brush.
How deep should the hole be drilled?
With a few exceptions, the drill hole depth must be greater than the anchoring depth. With plastic plugs in particular, the space is needed to accommodate the screw, which must always protrude from the tip of the plug.
Correct installation
In anchor installation, there are three different installation methods:
Pre-positioned installation: The anchor is flush with the anchoring base.
The fixture is mounted onto the anchor,
and the screw is inserted through the fixture into the anchor.
Push-through installation: The expansion part of the anchor is inserted through the fixture into the anchoring base. The anchor head rests against the fixture, and the anchor length determines the maximum fixture thickness.
Stand-off installation: This method is used to mount a component at a specific distance from the anchoring base.
For this type of installation, metal anchors with internal threads are typically used to accommodate threaded rods with a locknut.
Stand-off installation is commonly used to compensate for uneven surfaces, suspend ceilings, or bridge insulation, for example, with Thermo Proof.
General safety instructions:
- The anchoring depth of the anchor must be observed.
- Drilling method and drill hole cleaning must be adapted to the building material.
- For heavy-duty fixings: Sizing in compliance with the approvals.
- The recommended loads only apply to installation in the building material, not for installation in joints.
- Approved plugs must be used for fixings where safety is of importance.
Should I use approved anchors?
To answer this, you need to ask yourself the following questions:
- Is there a risk to life and limb if the fixing fails?
- Is a significant financial loss to be expected if the fixing fails?
- Is an approval for the anchor required in the specifications or similar documents?
If you have answered yes to one or more of the questions, fixings approved by the building authorities must be used.
General note:
Fixings must be installed and dimensioned in accordance with applicable regulations and standards. In case of doubt, please contact our Technical Hotline at +49 (0) 7576 / 9295-123 or technik@tox.de.
How a fixing works
To ensure that the different forces acting on the anchor are safely transferred to the substrate, various load-bearing mechanisms are used.
Frictional locking: Here, the expansion part of the plug is pressed against the drill hole wall in the building material.
Form locking: Here, the fixing geometry adapts to the shape of the substrate or the drill hole.
Bonding: Here, the anchor is connected to the substrate using a mortar.
Choosing the right plug and screw length
The following guidelines apply to the correct drill hole, plug and screw length:
- Drill hole depth = plug length + at least 10 mm
- Screw length = plug length + fixture thickness + 5 mm (must protrude from the plug tip)
- Drill Ø = plug Ø
Exceptions apply to the anchors Ytox, Dual Force, and Impact. Please refer to the information on the packaging.
How do I choose the right plug diameter?
For a secure fixing, not only the correct anchor length but also its size is crucial. As a general rule, the plug diameter matches the drill hole diameter, while the screw diameter is typically 2-3 mm smaller.
The optimal approach: Determine the correct screw size (diameter) based on the fixture. +2-3 mm then corresponds to the correct plug and drill hole diameter. Of course, factors such as building material, correct length, and location (indoor or outdoor) must also be considered.
Plug and fixing types
All-purpose plug:
Due to its expansion or knotting function, the all-purpose plug is suitable for almost all building materials. The plug knots behind the substrate or expands in solid materials, like an expansion plug. Anti-rotation locks prevent the plug from spinning within the material. Some of the most common all-purpose plugs include TRI, TRIKA, and Deco.
Areas of application:
Fixing of kitchen cabinets, shelves, TV sets, pictures, letterboxes, hanging baskets, curtain rails, towel rails, skirting boards, lamps, cable ducts, lightweight mirror cabinets, etc.
Heavy-duty anchors:
Heavy-duty anchors are typically steel anchors that secure themselves in the material through expansion. In addition to mechanical heavy-duty anchors, there are also bonded heavy-duty anchors, where a steel element is “glued” into the drill hole using mortar. Examples of mechanical heavy-duty anchors include the S-Fix bolt anchor, Dual Force heavy-duty anchor, and Impact drop-in anchor. The expansion of the heavy-duty anchor within the component creates a friction-based fixing.
Areas of application: Fixing of wood and steel structures, railings, ladders, cable trays, beams, awnings, canopies, security doors, substructures, etc.
Hook plugs:
Plugs with hook or eye bolt, e.g. the cavity hook plug Pirat Skippi, the all-purpose hook plugs Pirat Will & Bill or the plasterboard hook plug Pirat Leslie.
Areas of application: Fixing of wall cabinets, coat racks, shelves, lights, hammocks, clotheslines, pictures, hanging planters, etc.
Sanitary fixings:
Various fixing systems for the installation of sanitary fixtures, featuring perfectly matched components, such as the Oase washbasin fixing, Piss-Fix urinal fixing, or Toilet floor-standing WC fixing.
Areas of application:
Fixing of mirrors, glass panels, washbasins, consoles, boilers, urinals, floor-standing WCs, ceramic shelves, and sinks.
Frame plugs:
Frame plugs consist of a plastic sleeve and a matching screw. When the screw is tightened, the plastic sleeve expands and anchors itself in the drill hole. Frame plugs are installed in push-through installation. They include, for example, the Attack Metal metal stud fixing, the Apollo all-purpose frame plug or the Fassad frame plug.
Areas of application:
For anchoring window frames, door frames, kitchen cabinets, wooden substructures, coat racks, metal stud profiles, sheets, cable ducts, substructures, wooden beams, etc.
Cavity fixings:
Cavity fixings are designed for securely fixing components to thin walls with a hollow space behind them. They are ideal for installations in metal profiles, drywall panels (Rigips), or even in ceiling walls of some older buildings. Examples of cavity fixings include the Spiral plasterboard plug, Spagat spring-toggle, and Acrobat metal cavity plug.
Areas of application:
For fixing pictures, lights, electrical switches, signs, curtain rods, spice racks, hanging planters, mirrors, coat racks, etc.
Insulation plugs:
There are two different types of insulation plugs:
1. Fixings in insulation materials:
Lighter elements can be fixed directly into the insulation layer, as the conical thread of the plugs compresses the insulation, creating a strong hold. Additionally, thermal bridges are prevented. Examples of these fixing systems include Thermo and Thermo Plus.
Areas of application:
For fixing signs, lamps, etc.
2. Fixing insulation materials to exterior walls:
These fixing systems include, for example, the Husky or Keeper insulation plug.
Areas of application:
For fixing pressure-resistant, self-supporting insulation boards, soft insulation materials such as glass wool, rock wool, foils, etc.
Chemical anchors / composite mortar:
Injection mortar (= two-component adhesive) is a bonding agent composed of two components (resin and hardener). Mixing these components initiates the curing reaction. To apply, use a cartridge gun to inject the injection mortar from the cartridge into the cleaned drill hole. Then, insert a threaded rod or internal threaded sleeve. In hollow bricks, a plastic sieve sleeve prevents the mortar from spreading too much within the material, ensuring better adhesion to the brick. Once fully cured, the resin mortar becomes solid. An example of an injection mortar is Liquix Pro 1.
Areas of application:
For fixing awnings, canopies, steel structures, ladders, high racks, railings, etc.
Safe application of injection mortar: For safe and easy application of injection mortars, it is best to use the TOX Liquix Blaster cartridge gun. Its robust metal construction, non-slip grip, and high transmission ratio of 1:18 require minimal effort and ensure better dispensing of the injection mortar compared to similar products.
Tips & Tricks
How can I mount a 60” flat-screen TV (approx. 40 kg) on a drywall?
To mount heavy objects on drywall, we recommend using our Acrobat metal cavity plug. If the TV is mounted on an extendable telescopic arm, the lever effect of the swivel arm further increases the tensile force on the TV. This can pose a risk of the drywall breaking.
Here’s a useful trick:
Plasterboard panels are usually mounted on struts every 62.5 cm when building drywalls. These struts can be found by tapping the walls. The closer you mount to a strut, the better the wall will hold the weight of the TV.
The heavy flat screen can be fixed directly to a strut using our Acrobat metal cavity plug or our Spagat or Spagat Pro spring-toggle.
How do I find out the thickness of the plasterboard in my kitchen?
Simply perform a test drilling with a small drill diameter. Bend one end of a wire or alternatively a paperclip by about 4 mm and measure the remaining length from the bend. Then, insert the wire into the hole and pull it back until it meets resistance. Now, measure the length of the wire protruding from the hole. By subtracting this from the total remaining length of the wire (remaining length = length from the bend), you can determine the thickness of your wall panels.
How do I fix a wall cabinet in a drywall?
The best way to fix objects to drywall is with our cavity plug. However, an even stronger holding effect is achieved if the object, e.g. a wall cupboard, is fixed with the Acrobat metal cavity plug or our Spagat or Spagat Pro to or near wall struts, which are usually located every 62.5 cm in a drywall. These struts can be found by tapping the walls or using a locating device.
What do I need to consider if I want to install fixings outdoors?
For fixings in outdoor areas, you should make sure to use components made of stainless steel.
For heavy loads, we recommend our S-Fix Pro 1 bolt anchor and or our Liquix Pro 1 composite mortar. For lighter fixings, we recommend our TRI and TRIKA all-purpose plugs, the Barracuda and Bizeps expansion plugs and our frame and insulation plugs, depending on the masonry.
How do I drill correctly into a tile?
Simply apply masking tape to the spot where the hole will be drilled. The tape prevents the drill bit from slipping on the tile and helps protect the tile glaze from chipping. Then, carefully position the drill (using a tile or masonry drill bit) and drill the hole at low speed (without impact).
