ASSY^®plus FT, countersunk head timber screw

ASSY plus FT countersunk head screws are full-thread screws that can be used universally within the new construction and renovation sector. They are ideal for reinforcement connections, lateral compression reinforcement or lateral tensile reinforcement in timber construction, carpentry, timber house and element construction.

Wood/metal connections

Wood/metal connections may be required in modern timber construction. Shear connections using ASSY plus FT mean greater forces can be tolerated. Due to a high-precision transmission of force, the countersunk head variant is particularly well-suited to this. The perfect aid for gentle transmission of forces and establishing effective static connections is the 45° angled washer in combination with ASSY plus FT countersunk head screws.

Lateral pressure intensification with truss support

With a truss support, the ASSY plus FT absorbs the compressive force to be transmitted. The head, in conjunction with the screw thread, introduces the force into the screws via an intermediate steel sheet and distributes it evenly across all full-thread screws in the entire wooden cross-section. The load-bearing capacity of the support is increased and compression of the wooden cross-section is avoided.

General lateral compression/lateral tensile reinforcement

The pressure and tensile strengths of timber across the wood grain are low. The ASSY plus FT screws allow you to increase the lateral pressure and tensile strengths of the wood, using less timber and designing more effectively.

Lateral tensile reinforcement, notches and breakthroughs

Reinforcement for preventing failure of glued trusses or other supports by exceeding the tensile strength of the wood can be carried out quickly and reliably with the ASSY plus FT. Compared with conventional reinforcements such as glued-in threaded rods or side beam reinforcements using wooden material panels, this enables visually appealing solutions and significantly reduces the required assembly time.

Lateral tensile reinforcement with ASSY plus FT when connecting main and secondary beams with moulded metal parts:

The weak point when connecting main and secondary beams with moulded metal parts is the top centre connecting row of the nails (danger of cracking). The lateral tensile reinforcement of the main beam using the ASSY plus FT in the joist hanger area can eliminate the risk of lateral failure.

Main/secondary beam connection

To date, main/secondary beam connections are made with moulded metal parts, such as joist hangers or concealed beam connectors that are time-consuming to install. The ASSY plus FT full-thread screw provides a time-saving and invisible alternative. By screwing in the ASSY plus FT at an angle of 45°, the screws absorb the lateral forces of the connection. Ideal for the application: FT-fix setting template.

False edge and lateral support beam reinforcement

It is often necessary to reinforce existing beams or rafters, especially when renovating old buildings. With the reinforcement types of false edge and lateral support beam reinforcement, the ASSY plus FT screw offers effective, cost-efficient technologies for increasing load-bearing capacity of the beams and reducing bending.

Prefabricated house construction/timber frame construction

ASSY plus FT is the optimum problem-solver in prefabricated house construction as well. Thanks to the full thread, it can absorb significantly greater tensile, pressure and shear loads. The connection is therefore not limited due to exceeding the head pull-through resistance. The drill tip ensures that the substructure does not splinter or crack during screwing in when the short edge distances are complied with, which is often the case with screws without a drill tip.

Rafter/purlin connection

Current rafter-purlin anchors require time-consuming assembly and also have a low load-bearing capacity. The ASSY plus FT is therefore an effective alternative with benefits in terms of assembly time. The existing weak point of an ASSY 3.0 countersunk head screw or an ASSY 3.0 SK, the head pull-through, can therefore be ignored with the ASSY plus FT. The result is a lasting connection even if the wooden cross-section subsequently dries out and shrinks.

Coupling purlins

In the construction of commercial and industrial buildings, the rafter-supporting purlins are generally formed as coupling purlins. The single-field beam coupling is used to create multiple field beams. The load-bearing capacity is increased and, in return, smaller material cross-sections can be used. With help, a quick and easy connection can be created. An ASSY SK screw (consolidation) and, depending on the load, ASSY plus FT screws, 6 or 8 mm in diameter, are inserted at right angles at each connection point. Pre-drilling is not necessary. The wood cross-sections can be kept small due to the short edge distances of the ASSY plus FT. Compared to a plate dowel assembly, the elaborate setting of dowels and bolts is eliminated as is the need to subsequently tighten the bolt nuts correctly. A powerful cordless drill is all that is required for installation of the screws.

Footing beams/edge beams

When designing houses with a timber frame construction, it was common up until now to produce the walls in the entire story. The ceiling beam position therefore lay on the wall frame of the lower story in each case. As a result, the air-tight level and the outer wall insulation were penetrated by the beam. Therefore, there is an increasing tendency to have the outer walls run through over the stories. Thanks to edge beam fastening with ASSY plus FT full thread screws, the fastening of the footing beams/edge beams for securing the ceiling can now be produced quickly, efficiently and easily in the form of a simple shear connection. With this design version, the screw-in template FT-fix is also suitable for adjusting the screw-in angle and the screw spacing.

Abutment renovation

There is hardly any old building with wooden beam ceilings that is completely free of damage on its load-bearing ceilings. Wood integrated in the masonry can be infected by fungus or insects. The beams may have rotted off or become heavily damaged at the point of support. Using laterally bolted reinforcing lugs, these points can be quickly and easily renovated and the load-bearing capacity of the beams is restored. This eliminates the need to completely replace the damaged beams.

Beam dowel replacement for two-cut wood/wood connections

To create a simple traditional beam dowel connection, high assembly precision is required. In practice, this often leads to implementation problems. A visually cleaner and financially attractive alternative is the creation of double shear wood/wood connections using ASSY plus FT screws. Installation differences can easily be compensated for with equivalent load-bearing capacities. Compared with the beam dowel connection, a smaller diameter is required due to the beneficial impact of the screw's hooking effect.

Wooden/concrete composite ceiling

A ceiling renovation employing a wood and concrete composite is the optimum method for increasing the load-bearing capacity where the beam spacings and support widths are particularly great, or where there are very high rated loads. 10 mm ASSY plus FT countersunk head screws with special FP connectors can be used to achieve maximum span width and efficient production in dry construction work. The FP connectors and ASSY plus FT act as shear connectors therein and absorb the shear flow between the wooden beams and the concrete slab. This eliminates the time-consuming installation of shear connectors made from expanded metal. ASSY plus FT has its own European Technical Approval (ETA13/0029) for this method.