TIMBER SCREWS AND DECK FASTENING

TIMBER,

CONCRETE,

METAL TERRACES AND FAÇADES

PARTIALLY THREADED - COUNTERSUNK HEAD

PLATE FASTENING

PARTIALLY THREADED - FLANGE HEAD

CONCRETE

TIMBER-TO-CONCRETE

CONCRETE AND MASONRY

FULLY THREADED - CYLINDRICAL HEAD

FULLY THREADED - COUNTERSUNK HEAD

METAL

TIMBER-TO-METAL

FASTENING METAL SHEET

DOUBLE THREAD

DECKS AND FACADES

HEADQUARTERS

• product development

• certification

• quality check

MANUFACTURING PLANT

INCREASINGLY FAST, SECURE, TECHNOLOGICAL CONNECTIONS

We have a new plant in Italy that enhances the development, production and distribution of screws and connectors.

We have supported timber construction for more than 30 years because we believe it is the right way to build a better future. We design in Alto Adige, we produce in Italy and around the

world, we export everywhere. Our screws are associated with a unique identification code that guarantees traceability from raw material to marketing.

Connecting worlds, materials and people is what we do best, ever since.

rothoblaas.com

The service classes are related to the thermo-hygrometric conditions of the environment in which a timber structural element is installed. They relate the temperature and humidity of the surroundings to the water content within the material.

ATMOSPHERIC CORROSIVITY CLASSES

EXPOSURE

WOOD CORROSIVITY CLASSES

Corrosion caused by wood depends on the wood species, wood treatment and moisture content. Exposure is defined by the TE category as indicated. The corrosivity of wood only affects the connector part inserted in the wooden element.

MOISTURE LEVEL

DISTANCE FROM THE SEA

Corrosion caused by the atmosphere depends on relative humidity, air pollution, chloride content and whether the connection is internal, external protected or external. Exposure is described by the CE category which is based on category C as defined in EN ISO 9223. Atmospheric corrosivity only affects the exposed part of the connector. use

POLLUTION

(i.e. not directly exposed to rain or precipitation), in uninsulated and unconditioned structures

elements directly exposed to the weather and not permanently exposed to water elements immersed in soil or water (e.g. foundation piles and marine structures) saturated

HOW MUCH DO WE KNOW ABOUT SCREWS?

Theory, practice, experimental campaigns: putting it all together on screws takes years of lectures, workshops and construction sites. We make it available to you in 70 pages that are extra catalogue. Because our experience is in your hands.

Scan the QR code to download the smartbook

COMPLETE RANGE

HEADS AND TIPS

HEAD TYPE

COUNTERSUNK WITH RIBS

HBS, HBS COIL, HBS EVO C4/C5, HBS S, VGS, VGS EVO C4/C5, VGS A4, SCI A2/A4, SBS, SPP, MBS

FLANGE

TBS , TBS MAX, TBS EVO C4/C5, TBS S, FAS A4

FLAT FLANGE

TBS FRAME

COUNTERSUNK SMOOTH

HTS, DRS, DRT, SKS EVO, SBS A2, SBN, SBN A2, SCI HCR

COUNTERSUNK 60°

SHS, SHS AISI410, HBS H

ROUND

LBS, LBS EVO, LBS H, LBS H EVO

HEXAGONAL

KOP, SKR EVO, VGS, VGS EVO, MTS A2, SAR

CONE-SHAPED

KKT A4 COLOR, KKT A4, KKT COLOR

PAN HEAD

HBS P, HBS P EVO, KKF AISI410

REINFORCED PAN HEAD

HBS PLATE, HBS PLATE EVO, HBS PLATE A4

CONVEX

EWS A2, EWS AISI410, MCS A2

CYLINDRICAL

VGZ, VGZ EVO C4/C5, VGZ H, DGZ, CTC, MBZ, SBD, KKZ A2, KKZ EVO C5, KKA AISI410, KKA COLOR

BUGLE

DWS, DWS COIL

TIP TYPE

3 THORNS

SELF-DRILLING

SHARP

SHARP SAW

HBS S, TBS S VGS

SHARP SAW NIBS (RBSN)

SHARP 2 CUT

KKT COLOR

STANDARD FOR WOOD

MBS, MBZ, KOP, MTS A2

HARD WOOD TIMBER

HBS H, VGZ H

HARD WOOD (STEEL - to - TIMBER)

LBS H, LBS H EVO

HARD WOOD (DECKING)

KKZ A2, KKZ EVO C5

SKR EVO, SKS EVO

METAL (TAPERED TIP) CONCRETE

SBD

METAL (WITH FINS)

SBS, SBS A2, SPP

METAL (WITHOUT FINS)

SBD, SBN, SBN A2, KKA AISI 410, KKA COLOR

RESEARCH & DEVELOPMENT

Extensive test campaigns carried out in Rothoblaas' own laboratories and at external institutions on softwood, hardwood and LVL have resulted in the development of a performing product in every respect.

Thanks to the 3 THORNS tip, minimum installation distances are reduced. More screws can be used in less space and larger screws in smaller elements. Costs and time for project implementation are reduced.

REDUCTION OF MINIMUM DISTANCES

Featuring raised slitting elements and an umbrella thread tip ensures a quick initial grip and easy installation, reduces torsional stress on the screw and minimises timber damage. The aesthetic finish

LEGEND standard tip standard tip (with pre-drilled hole)

3 THORNS tip self-drilling tip

To be inserted, the screw must overcome the strength force of the wood. The screwing force, measured through the insertion moment (Mins), is only minimised if the tip is performing.

Thanks to its counter-threaded slitting elements, the 3 THORNS tip facilitates insertion of the screw into the grains without damaging them.

It acts as a guide hole, allowing the reduction of edge distances and screw spacing. At the same time, it prevents wooden element's cracking and mechanisms of brittle failure of the connection.

The graph shows the development of the insertion moment for screws with different geometric characteristics of the drill bit and the same boundary conditions (screw diameter, thread length and type, timber substrate material, applied force) as a function of the penetration length (Lins).

The accumulated torsional stress on the screw with a 3 THORNS tip (C) during its insertion is significantly lower than in the case of screws with standard tips (A) and is close to the screwing with pre-drilling hole (B).

The sequence represents the test procedure for the evaluation of minimum distances for axially stressed screws according to EAD 130118-01-0603.

The test is performed by tightening the screw, unscrewing it after 24 hours and filling the hole with dye to check its diffusion inside the wooden element. The portion of wood affected by the insertion of the screw is proportional to the red area.

The 3 THORNS tip (C) exhibits similar behaviour to that of the standard screw inserted with pre-drilling hole (B), tending towards the case of the self-drilling tip screw (D).

standard tip

3 THORNS tip

standard tip (with pre-drilled hole) self-drilling tip

The picture shows the insertion of screws with different tips and shows the change in pull-through depth after 1.0 second of tightening.

COMPLETE RANGE

MATERIALS AND COATINGS

CARBON STEEL WITH COATING

C5 EVO ANTI-CORROSION COATING

Multi-layer coating capable of withstanding outdoor environments classified C5 according to ISO 9223. Salt spray exposure time (SST) according to ISO 9227 greater than 3000h (test carried out on screws previously screwed and unscrewed in Douglas fir).

C4 EVO ANTI-CORROSION COATING

Inorganic-based multilayer coating with a functional outer layer of epoxy matrix with aluminium flakes. Suitability for atmospheric corrosivity class C4 proven by RISE

ORGANIC ANTI-CORROSION COATING

Coloured organic-based coating that provides excellent resistance to atmospheric and wood corrosive agents in outdoor applications.

ELECTROLYTIC GALVANIZING

Coating consisting of a layer of electrolytic galvanizing with Cr passivation; standard for most connectors

STAINLESS STEEL

HIGH CORROSION RESISTANT - CRC V

Austenitic stainless steel. It is characterised by high molybdenum and low carbon content. It offers very high resistance to general corrosion, stress corrosion cracking, intergranular corrosion and pitting. The appropriate choice for exposed fasteners in indoor pools.

STAINLESS STEEL A4 | AISI316 - CRC III

Austenitic stainless steel. The presence of molybdenum provides high resistance to generalised and crevice corrosion.

STAINLESS STEEL - A2 | AISI304 - CRC II

Austenitic stainless steel. It is the most common of the austenitic steels. It offers an excellent level of protection against generalised corrosion.

STAINLESS STEEL - A2 | AISI305 - CRC II

Austenitic stainless steel similar to A2 | AISI304. This alloy contains slightly more carbon than A2 | AISI304, making it more workable in production.

AISI410 STAINLESS STEEL

Martensitic stainless steel, characterised by its high carbon content. Suitable for outdoor applications (SC3). This stainless steels offers the highest mechanical performance compared to the other available stainless steels.

LEGEND:

atmospheric corrosivity classes

Rothoblaas experience Rothoblaas experience wood corrosivity classes colour

Atmospheric corrosivity classes defined according to EN 14592:2022 based on EN ISO 9223 and EN 1993-1-4:2014 (for stainless steel, an equivalent atmospheric corrosivity class was determined considering only the influence of chlorides and without a cleaning maintenance). Wood corrosivity classes according to EN 14592:2022.

For further information, see SMARTBOOK TIMBER SCREWS at www.rothoblaas.com.

RESEARCH & DEVELOPMENT

EVO COATINGS

Rothoblaas research projects result in coatings that meet the most complex market requirements. Our goal is to offer stateof-the-art fastening solutions that guarantee uncompromising mechanical strength and corrosion resistance.

Atmospheric corrosivity class C4: areas with a high concentration of pollutants, salts or chlorides. For example, heavily polluted urban and industrial areas and coastal zones.

Inorganic-based multilayer coating with a functional outer layer of epoxy matrix with aluminium flakes.

1440 h

Hours of exposure in salt spray test according to EN ISO 9227:2012 in the absence of red rust.

DISTANCE FROM THE SEA

RESISTANCE TO CHLORIDE EXPOSURE(1) C4 EVO anti-corrosion coating (2) C5 EVO anti-corrosion coating (2)

Atmospheric corrosivity class C5: areas with a very high concentration of salts, chlorides or corrosive agents from production processes. For example, places by the sea or areas of high industrial pollution.

Organic-based multilayer coating with a functional layer. The top-coat has a sealing function, which delays the start of the corrosion reaction.

Hours of exposure in salt spray test according to EN ISO 9227:2012 in the absence of red rust carried out on previously screwed and unscrewed Douglas fir screws.

C4 C5

TIMBER

VGS

FULLY

VGS EVO FULLY

60° COUNTERSUNK SCREW

SMALL HEAD AND 3 THORNS TIP

The 60° head and 3 THORNS tip allow easy insertion of the screw into small thickness without creating openings in the timber.

ENLARGED IMPRESSION

Compared to common carpentry screws, it has a larger Torx cavity: TX 25 for Ø4 and 4.5, TX 30 for Ø5. It is the right screw for users requiring strength and precision.

FASTENING ON TONGUE AND GROOVE BOARDS

For fixing beads or small elements, the 3.5 mm diameter version is perfectly suited for application in joints.

Ø4 - Ø4,5 - Ø5

DIAMETER [mm]

LENGTH [mm]

SERVICE CLASS

ATMOSPHERIC CORROSIVITY

WOOD CORROSIVITY

MATERIAL

electrogalvanized carbon steel

FIELDS OF USE

• tongue-and-groove boards

• timber based panels

• fibreboard, MDF, HDF and LDF

• plated and melamine faced panels

• solid timber

• glulam (Glued Laminated Timber)

• CLT and LVL

CODES AND DIMENSIONS

( * ) 40 26 14 500 SHS3550 ( * ) 50 34 16 500

( * ) Not holding CE marking.

GEOMETRY AND MECHANICAL CHARACTERISTICS

GEOMETRY

(1) Pre-drilling valid for softwood.

(2) Pre-drilling valid for hardwood and beech LVL.

CHARACTERISTIC MECHANICAL PARAMETERS

For applications with different materials please see ETA-11/0030.

screws inserted WITHOUT pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

screws inserted WITH pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

NOTE on page 19

EFFECTIVE NUMBER FOR SHEAR LOADS

The load-bearing capacity of a connection made with several screws, all of the same type and size, may be lower than the sum of the load-bearing capacities of the individual connection system. For a row of n screws arranged parallel to the direction of the grain at a distance a1 , the characteristic effective load-bearing capacity is equal to:

Ref,V,k = RV,k nef

The n ef value is given in the table below as a function of n and a1

1( * )

( * ) For intermediate a1 values a

SHEAR TENSION

ε = screw-to-grain angle

GENERAL PRINCIPLES

• Characteristic values comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• Design values can be obtained from characteristic values as follows:

Rd = Rk kmod

γM

The coefficients γ M and kmod should be taken according to the current regulations used for the calculation.

• For the mechanical resistance values and the geometry of the screws, reference was made to ETA-11/0030.

• Sizing and verification of the timber elements and panels must be done separately.

• The screws must be positioned in accordance with the minimum distances.

• The characteristic shear resistances are calculated for screws inserted without pre-drilling hole. In the case of screws inserted with pre-drilling hole, greater resistance values can be obtained.

• Shear strengths were calculated considering the threaded part fully inserted in the second element.

• The characteristic panel-timber shear strengths are calculated considering an OSB3 or OSB4 panel, as per EN 300, or a particle board panel, as per EN 312, with thickness SPAN and density ρ k = 500 kg/m3

• The thread withdrawal characteristic strength has been evaluated considering a fixing length equal to b.

• The head pull-through characteristic strength was calculated using timber elements.

MINIMUM DISTANCES

NOTES

• The minimum distances comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• The minimum spacing for all panel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,85.

• In the case of joints with elements in Douglas fir (Pseudotsuga menziesii), the minimum spacing and distances parallel to the grain must be multiplied by a coefficient of 1.5.

NOTES

• The characteristic timber-to-timber shear strengths were evaluated considering both an ε angle of 90° (RV,90,k ) and 0° (RV,0,k ) between the grains of the second element and the connector.

• The characteristic panel-timber shear strengths were evaluated considering an angle ε of 90° between the grains of the timber element and the connector.

• The characteristic thread withdrawal resistances were evaluated considering both an ε angle of 90° (Rax,90,k ) and of 0° (Rax,0,k ) between the grains of the timber element and the connector.

• For the calculation process a timber characteristic density ρ k = 385 kg/m3 has been considered.

For different ρ k values, the strength on the table (timber-to-timber shear and tensile) can be converted by the kdens coefficient.

R’V,k = RV,k kdens,v

R’ax,k = Rax,k kdens,ax

R’head,k = Rhead,k kdens,ax

Strength values thus determined may differ, for higher safety standards, from those resulting from an exact calculation.

• The spacing a1 in the table for screws with 3 THORNS tip and d1≥5 mm inserted without pre-drilling hole in timber elements with density ρ k ≤ 420 kg/m3 and load-to-grain angle α=0° was assumed to be 10∙d based on experimental tests; alternatively, adopt 12∙d in accordance with EN 1995:2014.

SHS AISI410

60° COUNTERSUNK SCREW

SMALL HEAD AND 3 THORNS TIP

The concealed 60° head and 3 THORNS tip allow easy insertion of the screw into small thickness without creating openings in the timber.

OUTDOOR ON ACID WOOD

Martensitic stainless steel. This stainless steels offers the highest mechanical performance compared to the other available stainless steels. Suitable for outdoor applications and on acid wood, but away from corrosive agents (chlorides, sulphides, etc.).

SMALL ELEMENTS FASTENING

The smaller diameter versions are ideal for fixing beads or small elements, the 3.5 mm diameter version is perfectly suited for fastening tongue-and-groove boards.

DIAMETER [mm]

LENGTH [mm]

SERVICE CLASS

ATMOSPHERIC CORROSIVITY

WOOD CORROSIVITY

MATERIAL

OF USE

• timber based panels

• solid timber

• glulam (Glued Laminated Timber)

• CLT, LVL

•

woods and acid woods

martensitic

WINDOWS AND DOORS ON THE OUTSIDE

SHS AISI140 is the right choice for fastening small outdoor elements such as beads, façades and window/door frames.

External casing slats fixed with 6 and 8 mm diameter SHS AISI410 screws.

Fastening hardwood and acid wood in farfrom-sea environments with SHS AISI410 8 mm diameter.

GEOMETRY AND MECHANICAL CHARACTERISTICS

GEOMETRY

(1) Pre-drilling valid for softwood.

(2) Pre-drilling valid for hardwood and beech LVL.

CHARACTERISTIC MECHANICAL PARAMETERS

For applications with different materials please see ETA-11/0030.

SHS N AISI410 - black version

CODES AND DIMENSIONS APPLICATION

ρ k = 665-760 kg/m3 pH ~ 3,9

ρ k = 580-600 kg/m3 pH = 3,4-3,7

ρ k = 690-960 kg/m3 pH = 3,4-4,2

ρ k = 550-980 kg/m3 pH = 3,8-4,2

ρ k = 510-750 kg/m3 pH = 3,3-5,8

ρ k = 510-750 kg/m3 pH = 3,1-4,4

Possible installation on acid wood but away from corrosive agents (chlorides, sulphides, etc.).

ρ k = 490-630 kg/m3 pH ~ 3,9

ρ k = 500-620 kg/m3 pH ~ 3,8

Find out the pH and density of the various wood species on page 314 “aggressive” woods high acidity "standard" timbers low acidity

Specially designed to match façades made of charred wood, the black SHS N variant ensures perfect compatibility and offers an excellent aesthetic result. Thanks to its strength to corrosion, it can be used outdoors, allowing to create striking and long-lasting black façades. ( * ) Not holding CE marking.

FAÇADES IN DARK TIMBER

Douglas fir Pseudotsuga menziesii

Red oak Quercus rubra

American black cherry Prunus serotina

Maritime pine Pinus pinaster

Oak Quercus petraea

Oak or European oak Quercus robur

European chestnut Castanea sativa

Blue Douglas fir Pseudotsuga taxifolia

screws inserted WITHOUT pre-drilled hole

screws inserted WITH pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

NOTES

• The minimum distances comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• The minimum spacing for all panel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,85.

• In the case of joints with elements in Douglas fir (Pseudotsuga menziesii), the minimum spacing and distances parallel to the grain must be multiplied by a coefficient of 1.5.

geometry

SHEAR

timber-to-timber panel-to-timber

GENERAL PRINCIPLES

• Characteristic values comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• Design values can be obtained from characteristic values as follows: Rd = Rk kmod

γM

The coefficients γ M and kmod should be taken according to the current regulations used for the calculation.

• For the mechanical resistance values and the geometry of the screws, reference was made to ETA-11/0030.

• Sizing and verification of the timber elements and panels must be done separately.

• The screws must be positioned in accordance with the minimum distances.

• The characteristic shear strengths were evaluated by considering the threaded part fully inserted in the second element.

TENSION

thread withdrawal head pull-through

• The thread withdrawal characteristic strength has been evaluated considering a fixing length equal to b.

• The head pull-through characteristic strength was calculated using timber elements.

NOTES

• The characteristic shear and tensile strengths were evaluated considering both an ε angle of 90° (Rax,90,k ) between the grains of the timber element and the connector.

• For the calculation process a timber characteristic density ρ k = 385 kg/m3 has been considered. For different values of ρ k , the strength values in the table can be converted by the kdens,V coefficient (see page 19).

• For a row of n screws arranged parallel to the direction of the grain at a distance a1 , the characteristic effective shear bearing capacity Ref,V,k can be calculated by means of the effective number n ef (see page 18).

FULLY THREADED COUNTERSUNK SCREW

3 THORNS TIP

Thanks to the 3 THORNS tip, the screw can be installed without pre-drilling hole on even very thin joinery and furniture wood, such as melamine-faced panels, plated panels or MDF.

FINE THREAD

A fine thread is ideal for utmost screwing precision, even on MDF panels. The cavity for the Torx bit ensures stability and security.

LONG THREAD

The thread is 80% the length of the screw and the smooth part under head guarantees maximum coupling efficiency with fibreboard panels.

DIAMETER [mm]

LENGTH [mm]

SERVICE CLASS

ATMOSPHERIC CORROSIVITY

WOOD CORROSIVITY

MATERIAL

electrogalvanized carbon steel

FIELDS OF USE

• timber based panels

• fibreboard, MDF, HDF and LDF

• plated and melamine faced panels

• solid timber

• glulam (Glued Laminated Timber)

• CLT and LVL

( * ) 12 6

( * ) 16 10 500

20 14

HTS3516 ( * ) 16 10

HTS3520 ( * ) 20 14

GEOMETRY AND MECHANICAL CHARACTERISTICS

(1) For high density materials, pre-drilled holes are recommended based on the wood specie.

HINGES AND FURNITURE

The total thread and countersunk head geometry are ideal for fastening metal hinges when building furniture. Ideal for use with single bit (included in the package), easily exchanged in the driver bit holder. The new self-perforating tip increases the initial grip capacity of the screw.

MINIMUM DISTANCES FOR SHEAR LOADS

screws inserted WITHOUT pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

screws inserted WITH pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

MINIMUM DISTANCES

NOTES

• Minimum distances in accordance with EN 1995:2014.

• The minimum spacing for all steel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,7.

STRUCTURAL VALUES

NOTES

• The characteristic timber-to-timber shear strengths were evaluated by considering an angle ε of 90° between the grains of the second element and the connector.

• The characteristic panel-timber and steel-timber shear strengths were evaluated by considering an ε angle of 90° between the grains of the timber element and the connector.

• The shear strength characteristics on the plate are calculated considering the case of a thin plate (SPLATE = 0.5 d1 ).

• The characteristic thread withdrawal strength was evaluated by considering a 90° angle ε between the fibers of the timber element and the connector.

• The minimum spacing for all panel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,85.

• For the calculation process a timber characteristic density ρ k = 385 kg/m3 has been considered. For different values of ρ k , the strength values in the table (timber-to-timber shear, steel-to-timber shear and tensile) can be converted by means of the coefficient kdens (see page 42).

• The values in the table are independent of the load-to-grain angle.

STRUCTURAL

GENERAL PRINCIPLES

• Characteristic values according to EN 1995:2014.

• Design values can be obtained from characteristic values as follows: Rd = Rk kmod

γM The coefficients γ M and kmod should be taken according to the current regulations used for the calculation.

• Mechanical strength values and screw geometry comply with CE marking according to EN 14592.

• Sizing and verification of the timber elements, panels and metal plates must be done separately.

• The screws must be positioned in accordance with the minimum distances.

• The characteristic panel-timber shear strengths are calculated considering an OSB3 or OSB4 panel, as per EN 300, or a particle board panel, as per EN 312, with thickness SPAN

• The thread withdrawal characteristic strength has been evaluated considering a fixing length equal to b.

• The head pull-through characteristic strength was calculated using timber elements. In the case of steel-to-timber connections, generally the steel tensile strength is binding with respect to head separation or pull-through.

COUNTERSUNK SCREW

3 THORNS TIP

FAST

With the 3 THORNS tip, screw grip becomes more reliable and faster, while maintaining the usual mechanical performance. More speed, less effort.

JOINTS WITH SOUNDPROOFING PROFILES

The screw has been tested and characterised in applications with soundproofing layers (XYLOFON) interposed on the shear plane.

The impact of acoustic profiles on the mechanical performance of the HBS screw is described on page 74

NEW-GENERATION WOODS

Tested and certified for use on a wide variety of engineered timbers such as CLT, GL, LVL, OSB and Beech LVL.

Extremely versatile, the HBS screw guarantees the use of new-generation woods for the creation of increasingly innovative and sustainable structures.

DIAMETER [mm]

LENGTH [mm]

SERVICE CLASS

ATMOSPHERIC CORROSIVITY

WOOD CORROSIVITY

MATERIAL

electrogalvanized carbon steel

FIELDS OF USE

• timber based panels

• fibreboard, MDF, HDF and LDF

• plated and melamine faced panels

• solid timber

• glulam (Glued Laminated Timber)

• CLT and LVL

• high density woods

CLT, LVL AND HARDWOOD

Values also tested, certified and calculated for CLT, LVL and high density woods such as beech LVL.

Wall insulation boards fastening with THERMOWASHER and HBS 8 mm diameter.

GEOMETRY AND MECHANICAL CHARACTERISTICS

Fastening CLT walls with 6 mm diameter HBS screws.

GEOMETRY

(1) Pre-drilling valid for softwood.

(2) Pre-drilling valid for hardwood and beech LVL.

CHARACTERISTIC MECHANICAL PARAMETERS

moment

resistance parameter

For applications with different materials please see ETA-11/0030.

softwood (softwood)

3,5 TX 15

4 TX 20

4,5 TX 20

5 TX 25

6 TX 30

MINIMUM DISTANCES FOR SHEAR LOADS | TIMBER

screws inserted WITHOUT pre-drilled hole

[mm]

a4,t [mm] 5∙d 18 20 23 5∙d 25 30 40 50

a4,c [mm] 5∙d 18 20 23 5∙d 25 30 40 50 60 a4,c [mm] 5∙d 18 20 23 5∙d 25

screws inserted WITH pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

NOTE on page 42

EFFECTIVE NUMBER FOR SHEAR LOADS

= RV,k nef

The n ef value is given in the table below as a function of n and a1

( * ) For intermediate a1 values a linear interpolation is possible.

STRUCTURAL VALUES | TIMBER

ε = screw-to-grain angle

NOTES and GENERAL PRINCIPLES on page 42

and GENERAL PRINCIPLES on page 42

STRUCTURAL VALUES | CLT

MINIMUM DISTANCES FOR SHEAR AND AXIAL LOADS | CLT

inserted WITHOUT pre-drilled hole

STRUCTURAL VALUES | LVL

NOTES and GENERAL PRINCIPLES on page 42 Internationality is also measured in the

STRUCTURAL VALUES | LVL

MINIMUM DISTANCES FOR SHEAR LOADS | LVL

screws inserted WITHOUT pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

STRUCTURAL VALUES

GENERAL PRINCIPLES

• Characteristic values comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• Design values can be obtained from characteristic values as follows: Rd = Rk kmod γM

The coefficients γ M and kmod should be taken according to the current regulations used for the calculation.

• For the mechanical resistance values and the geometry of the screws, reference was made to ETA-11/0030.

• Sizing and verification of the timber elements, panels and metal plates must be done separately.

• The screws must be positioned in accordance with the minimum distances.

• Shear strengths were calculated considering the threaded part fully inserted in the second element.

• The thread withdrawal characteristic strength has been evaluated considering a fixing length equal to b.

• The characteristic strength to head pull-through, with and without a washer, was evaluated using timber or timber based elements. In the case of steel-to-timber connections, generally the steel tensile strength is binding with respect to head separation or pull-through.

• In the case of combined shear and tensile stress, the following verification must be satisfied: Fv,d

• In the case of steel-to-timber connections with a thick plate, it is necessary to assess the effects of timber deformation and install the connectors according to the assembly instructions.

• For different calculation configurations, the MyProject software is available (www.rothoblaas.com).

NOTES | CLT

• The characteristic values are according to the national specifications ÖNORM EN 1995 - Annex K.

• For the calculation process, a mass density of ρ k = 350 kg/m3 has been considered for CLT elements and a mass density of ρ k = 385 kg/m3 has been considered for timber elements.

• The characteristics shear resistance are calculated considering a minimum fixing length of 4 d1

• The characteristic shear strength is independent from the direction of the grain of the CLT panels outer layer.

• The axial thread withdrawal resistance in the narrow face is valid for minimum CLT thickness tCLT,min = 10∙d1 and minimum screw pull-through depth tpen = 10∙d1

MINIMUM DISTANCES

NOTES | TIMBER

• The minimum distances comply with the EN 1995:2014 standard in accordance with ETA-11/0030.

• The minimum spacing for all steel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,7.

• The minimum spacing for all panel-to-timber connections (a1 , a2) can be multiplied by a coefficient of 0,85.

• In the case of joints with elements in Douglas fir (Pseudotsuga menziesii), the minimum spacing and distances parallel to the grain must be multiplied by a coefficient of 1.5.

NOTES | CLT

• The minimum distances are compliant with ETA-11/0030 and are to be considered valid unless otherwise specified in the technical documents for the CLT panels.

• Minimum distances are valid for minimum CLT thickness tCLT,min =10∙d1

• The minimum distances referred to "narrow face" are valid for minimum screw pull-through depth tpen = 10∙d1

NOTES | TIMBER

• The characteristic timber-to-timber shear strengths were evaluated considering both an ε angle of 90° (RV,90,k ) and 0° (RV,0,k ) between the grains of the second element and the connector.

• The characteristic panel-timber and steel-timber shear strengths were evaluated by considering an ε angle of 90° between the grains of the timber element and the connector.

• The characteristic plate shear strengths are evaluated considering the case of thin plate (SPLATE = 0.5 d1 ) and thick plate (SPLATE = d1 ) .

• The characteristic thread withdrawal resistances were evaluated considering both an ε angle of 90° (Rax,90,k ) and of 0° (Rax,0,k ) between the grains of the timber element and the connector.

• For the calculation process a timber characteristic density ρ k = 385 kg/m3 has been considered.

For different values of ρ k , the strength values in the table (timber-to-timber shear, steel-to-timber shear and tensile) can be converted by means of the coefficient kdens

R’V,k = RV,k kdens,v

R’ax,k = Rax,k kdens,ax

R’head,k = Rhead,k kdens,ax

ρ k [kg/m3 ] 350 380 385 405 425

Strength values thus determined may differ, for higher safety standards, from those resulting from an exact calculation.

NOTES | LVL

• For the calculation process, a mass density of ρ k = 480 kg/m3 has been considered for the softwood LVL elements and a mass density of ρ k = 385 kg/m3 has been considered for timber elements.

• The characteristic shear strengths are evaluated for connectors inserted on the side face (wide face) considering, for individual timber elements, a 90° angle between the connector and the grain, a 90° angle between the connector and the side face of the LVL element and a 0° angle between the force and the grain.

• The axial thread-withdrawal resistance was calculated considering a 90° angle between the grains and the connector.

• Screws shorter than the minimum in the table are not compatible with the calculation assumptions and are therefore not reported.

NOTES | LVL

• The minimum distances are compliant with ETA-11/0030 and are to be considered valid unless otherwise specified in the technical documents for the LVL panels.

• The minimum distances are applicable when using both parallel and cross grain softwood LVL.

• The minimum distances without pre-drilling hole are valid for minimum thickness of LVL elements tmin:

t1 ≥ 8,4 d - 9

t2 ≥ 11,4 d 75

where:

- t 1 is the thickness in mm of the LVL element in a connection with 2 wooden elements. For connections with 3 or more elements, t 1 represents the thickness of the most external LVL;

- t 2 is the thickness in mm of the central element in a connection with 3 or more elements.

SCREWING USING CATCH

Place the bit inside the CATCH screwing device and fasten it to the correct depth depending on the chosen connector.

CATCH is suitable with long connectors where the insert would otherwise tend to come out of the screw head space.

PARTIALLY THREADED SCREWS vs FULLY THREADED SCREW

Compressible elements are interposed between two timber beams and a screw is screwed centrally to evaluate its effect on the connection.

APPLICATION ON HARDWOODS

Pre-drill a hole of the required diameter (d V,H) and length equal to the chosen connector size using the SNAIL tip.

RELATED PRODUCTS

The partial thread screw (e.g. HBS) allows the joint to be closed. The threaded portion, inserted all the way inside the second element, allows the first element to slide on the smooth shank.

Install the screw (e.g. HBS).

Useful in case of screwing in corners, which usually do not allow exerting a great screwing force.

The fully threaded screw (e.g. VGZ) transfers the force by exploiting its axial strength and penetrates inside the timber elements without moving.

Alternatively, specific screws for hardwood applications (e.g. HBSH) can be used, which can be inserted without the aid of pre-drill hole

HBS SOFTWOOD

COUNTERSUNK SCREW

SAW TIP

Special self-perforating tip with serrated thread (SAW tip) that cuts the timber grains, facilitating initial grip and subsequent pull-through.

LONGER THREAD

Greater thread length (60%) to ensure superb joint closure and great versatility.

SOFTWOOD

Optimised geometry for maximum performance on the most common construction timbers.

DIAMETER [mm]

LENGTH [mm]

SERVICE CLASS

ATMOSPHERIC CORROSIVITY

WOOD CORROSIVITY

MATERIAL

electrogalvanized carbon steel

FIELDS OF USE

• timber based panels

• fibreboard and MDF panels

• solid timber

• glulam (Glued Laminated Timber)

• CLT and LVL

TIMBER ROOF

The screws’ fast initial grip makes it possible to create secure structural connections in all assembly conditions.

SIP PANELS

The size range is specially designed for the application of fasteners on medium and large structural elements, such as lightweight boards and frames, up to SIP and Sandwich panels.

CODES AND DIMENSIONS

5 TX 25

6 TX 30

RELATED PRODUCTS

GEOMETRY AND MECHANICAL CHARACTERISTICS

GEOMETRY

(1) For high density materials, pre-drilled holes are recommended based on the wood specie.

CHARACTERISTIC MECHANICAL PARAMETERS

screws inserted WITHOUT pre-drilled hole

d 1 [mm] 5 6 8

a 1 [mm] 12∙d 60 72 96 a1 [mm] 5∙d 25

a 2 [mm] 5∙d 25 30 40 a 2 [mm] 5∙d 25 30

a3,t [mm] 15∙d 75 90 120

a3,c [mm] 10∙d 50 60 80 a3,c [mm] 10∙d 50 60 80

a4,t [mm] 5∙d 25 30 40 a4,t [mm] 10∙d 50 60 80

a4,c [mm] 5∙d 25 30 40 a4,c [mm] 5∙d 25 30 40

α = load-to-grain angle

d = d1 = nominal screw diameter

screws inserted WITH pre-drilled hole

α = load-to-grain angle

d = d1 = nominal screw diameter

NOTE on page 49