Fasteners

Roof Screw Selection

CORRUGATED INTO TIMBER

50mm

65mm

CORRUGATED INTO STEEL

38mm

50mm

IBR INTO TIMBER

90mm

85mm

75mm

IBR INTO STEEL

65mm

85mm

Did you know?

The fastener length is determined by:

- Profile height of sheeting

- Compressed thickness of insulation

- Thickness of washers & seals

- Thickness of steel purlins

- Length of drill point and first 3 threads above drill point in case of steel purlins

- Minimum 35mm penetration into timber in case of timber purlins

Fastener point selection

Timber: Type 17 point

Thin gauge steel: stitching point

Thin gauge steel: zip point

Cold rolled steel: drill point (4.5mm capacity)

Hot rolled steel: drill point (12.5mm capacity)

Fastener head selection

Klip-tite, Klip-Lok, Brownbuilt, Saflok: Wafer head

Corrugated, IBR, Stitching, Laps: Hex flange head & seal

Classification & designation of corrosion resistance

Corrosion resistance class

C1 -

C2 -

C3 -

C4 -

C5 -

Atmosphere of intended use

General use in internal application.

General use in other than external applications but where significant levels of condensation occurs.

External use in mild, moderate industrial or marine environments.

Corrosivity categories C2 and C3 classified in accordance with ISO 9223.

External use in severe marine or industrial environment.

Corrosivity category C4 classified in accordance with ISO 9223.

External use in very severe marine or industrial environment.

Off shore environments.

Material Compatibility

Fastener coating must be compatible with sheeting to prevent galvanic corrosion and comply with manufacturer's warranty

Class 2 -

Electro plated

Class 3 -

Mech plated

Class 4 -

Mech plated

Class 5 -

Stainless steel

Galvanised sheeting

Galvanised, ZincAL, Chromadek & Colourplus sheeting

Aluminium & Stainless Steel sheeting

Our standard fastener range

22mm Class 3 Stitching Scew

25mm Class 3 Steel Screw

50mm Class 3 Steel Screw

65mm Class 3 Steel Screw

75mm DuoTapp Screw (for fixing into steel or timber)

65mm Class 3 Timber Screw

90mm Class 3 Timber Screw

Algoa Steel Vaal Winged Screw & BAZ washer

50mm Class 4 WINGED Steel Screw for Corrugated polycarbonate sheeting

75mm Class 4 WINGED Steel Screw for IBR polycarbonate sheeting

Ask our friendly sales consultants about our washers, colour caps, rivets, butyl stripseal, etc or get a price list here

Colour Caps

ALGOA STEEL VAAL

TEL 087 133 0722

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Fasteners

Roof Screw Selection

Did you know?

The fastener length is determined by:

- Profile height of sheeting

- Compressed thickness of insulation

- Thickness of washers & seals

- Thickness of steel purlins

- Length of drill point and first 3 threads above drill point in case of steel purlins

- Minimum 35mm penetration into timber in case of timber purlins

Fastener point selection

Timber: Type 17 point

Thin gauge steel: stitching point

Thin gauge steel: zip point

Cold rolled steel: drill point (4.5mm capacity)

Hot rolled steel: drill point (12.5mm capacity)

Fastener head selection

Klip-tite, Klip-Lok, Brownbuilt, Saflok: Wafer head

Corrugated, IBR, Stitching, Laps: Hex flange head & seal

Classification & designation of corrosion resistance

Corrosion resistance class

C1 -

​

​

​

C2 - ​

​

​

​

C3 -

​

​

​

C4 -

​

​

​

C5 -

​

​

​

Atmosphere of intended use

General use in internal application.

General use in other than external applications but where significant levels of condensation occurs.

External use in mild, moderate industrial or marine environments.

Corrosivity categories C2 and C3 classified in accordance with ISO 9223.

External use in severe marine or industrial environment.

Corrosivity category C4 classified in accordance with ISO 9223.

External use in very severe marine or industrial environment.

Off shore environments.

Material Compatibility

Fastener coating must be compatible with sheeting to prevent galvanic corrosion and comply with manufacturer's warranty

Class 2 -

Electro plated

​

Class 3 -

Mech plated

​

Class 4 -

Mech plated

​

Class 5 -

Stainless steel

​

Galvanised sheeting

Galvanised, ZincAL, Chromadek & Colourplus sheeting

Galvanised, ZincAL, Chromadek & Colourplus sheeting

Aluminium & Stainless Steel sheeting

Our standard fastener range

22mm Class 3 Stitching Scew

25mm Class 3 Steel Screw

50mm Class 3 Steel Screw

65mm Class 3 Steel Screw

​

75mm DuoTapp Screw (for fixing into steel or timber)

​

65mm Class 3 Timber Screw

C2 -