RHEINZINK® - Double Standing Seam

Product Overview

  RHEINZINK® - Double Standing Seam
  • Fine seam lines give a slim appearance
  • Harmonises with both traditional and modern architecture
  • Feasible with conical surfaces as well as concave and convex rounded surfaces
  • Feasible at a roof pitch from as low as 3°
  • Simple, efficient installation
  • Rain proof long-seam connection
  • Use of pre-shaped courses
  • Courses can be in lengths of up to 16.0 m
RHEINZINK® - Double Standing Seam

With respect to the material zinc, the dual standing seam counts as a development of the original wooden seam / simple standing seam. Since literature of 1899,  it has been the clear preference over other systems, for rooves with a slope of under 25° (minimum slope 3° or 5%). The name "dual standing seam" is characteristic of one of the of the classic long connection types  - courses installed alongside one another, outside of the water level. At a minimum seam height of 23 mm, the dual standing seam is rain proof without any additional treatment. The 25 mm high, dual standing seam produced with with pre-shaped courses has gained international acceptance. The profile is tilted and closed manually or by machine, using shaping machines. It is even possible to produce special shapes such as convex and concave curves or conical course without difficulty. The multitude of possible detail variations in the dual standing seam offers a subtle emphasis of shape and looks equally appropriate with both traditional architecture and modern designs.

Technology

         

System Description

  • Roof cover from 3° (ca. 5%) roof slope
  • Regulation roof slope  7° to 25°

The dual standing seam can be used for roof slopes from 3°. The profile edges are manufactured using roll forms or by hand. Seams are also closed either using a seam closing machine or by hand.

Installation of pre-shaped dual standing seam courses has become internationally standard. Filigree division of roof surfaces can be  can be achieved with a seam height of approx. 25 mm and a thin seam back.
Conical areas and even concave and convex rounded surfaces can easily be covered using the dual standing seam.
             
          Course Width / Metal Thickness
  • Standard course width approx. 530 mm (band width 600 mm)
  • Possible course widths 400 mm to 700 mm
  • Metal thickness 0.7 mm / 0.8 mm
The course width of approx. 530 mm (band width 600 mm) is the international standard for dual standing seam roofs, with metal thickness of 0.7 mm.

However, building practise experience dictates, in exceptional cases, that it is necessary to reduce the course width and increase the metal thickness. This can counteract possible deflections from high winds.

Note: Small waves in the courses can occur, due to specific material tensions for thin sheets.
             
          Course Length
  • Usual course length up to 10.00 m
  • In special cases up to 16.00 m
The general standard maximum course length is 10.00 m.

In special cases, courses of up to 16.00 m long can be installed. In this case, the fixing and connection details for the course must be adapted to the increased length.

If the max. possible course length is insufficient, then individual lengths may be attached with cross-joins.

Fixing

  • Indirect via bindings in the seam area
  • Indirect via binding strips in the tilts on the course end

Fixing is basically indirect via bindings in the seam area or binding strips in the tilts on the course end (in certain cases, individual bindings here as well).

Bindings are classified as fixed bindings, sliding bindings and long-sliding bindings. The number of bindings per sq m depends on the prevailing wind strengths, the fixing media and the roof construction selected. Further, the course width and metal thickness also significantly influence the number of bindings required.

Coil width/mm
Section width/mm*
Section width/mm**
Metal thickness /mm

 500
420
430
0.7		 570
490
500
0.7		 600
520
530
0.7		 670
590
600
0.7		 700
620
630
0.7		 800
720
730
0.8
Wind loads in kN/m²            
- 0.3
- 0.6
- 0.9
- 1.2
- 1.5
- 1.8
- 2.1
- 2.4
- 2.7
- 3.0
- 3.3
- 3.6
- 3.9
- 4.2
- 4.5
- 4.8
- 5.1

4/500
4/500
4/500
4/500
6/350
7/300
8/250
8/250
10/200
11/200
11/200
13/150
13/150
15/150
15/150
17/100
17/100

 4/500
4/500
4/500
4/500
6/350
7/300
8/250
8/250
10/200
11/200
11/200
13/150
13/150
15/150
15/150
17/100
17/100		 4/500
4/500
4/500
4/500
6/350
7/300
8/250
8/250
10/200
11/200
11/200
13/150
13/150
15/150
15/150
17/100
17/100		 4/500
4/500
4/500
4/500
6/300
7/300
9/250
9/250
10/200
11/150
11/150
13/150
 4/500
4/400
4/400
4/400
6/250
7/250
9/200
9/200
10/150		 4/400
4/400
4/400
4/400
6/250
7/250
9/200

Table: minimum number of RHEINZINK® bindings (per m²)/max. distance between bindings (mm) depending on loads

Note: Measurement of the bindings and distance between the bindings is based on a mean value with course lengths of approx. 3 m.
*   approx. course width when hand finished
**  approx. course width when machine finished

          Fixed Clip Area
  • Roof surface fixed clip area is between 1.0 m and 3.0 m.
In order to prevent the sections from slipping, a fixed clip area is allocated on the roof surface, depending on roof pitch.

Depending on section length, the portion with the fixed fasteners can be between 1 and 3 m long, but not more than a quarter of the section length.

Fixing Media

  • Mainly flat headed nail or roofing felt nails

In Europe, flat headed nails and roofing felt nails have become the accepted fixing media.

Fixing RHEINZINK® roofing is primarily dependent on the type and design of the base construction. Construction requirements taking account of snow and wind loads, as well as course width and metal thickness must considered when selecting fixing media.

Fixing Medium 2 each per clip Metal thickness 0,8mm

 Dimensions (in mm) Quality typ. Use in Base construction
(Comments s.b.)
1 2 3
Flat headed nail for Compressed air nailer 3,1x25 hot zinc dipped D 508 889 1074
Roofing felt nail 2,8x25 hot zinc dipped D - 751 -
Patented roofing felt nail 2,8x25 zinc-plated A 415 - -
Chipboard screw 4,0x20 zinc-plated DK/D - - 1262
Chipboard screw 4,0x25 zinc-plated DK/D - - 982
Roofing felt nail, threaded 2,5x25 zinc-plated DK - - 1019
Countersunk wood screw 4,5x25 zinc-plated DK - - 533
Threaded nail 3,5x30 coated S 829* - 1091*
Threaded nail 2,4x30 zinc-plated F 791* 787* -
Felt nail 2,5x25 hot zinc dipped F - 503 -

-   The combination was not taken into consideration with the measurements
*   The extraction values are higher in 30 mm thick wooden sheathing, as expected
1   Ta/Fi 24 mm wooden casing, V13 glass fibre bitumen roof sheeting
2   Ta/Fi 24 mm wooden casing
3   Building veneer plywood, waterproof, glued, 19mm, structured separator

Table: medium static extraction values (in Newtons) of standard binding fixing media for RHEINZINK® seamed roofs and façades, depending on base construction

Cross-Joints

  • Roof slope gradient level ≥ 3°
  • Simple cross-seam with additional soldered-on binding strips roof slope ≥ 10°
  • Simple cross-seam, roof slope ≥ 25°

To separate over-long course lengths and for design reasons, cross-joins can be shaped. Shaping of cross-joins is dependant on the slope of the roof.

          Gradient Level
  • Implementation from a roof slope of ≥ 3°
Gradient levels can be implemented from a roof slope of ≥ 3°. They can join parallel roof slopes or roofs with differing slopes. The gradient level can be implemented either with or without back ventilation, as well as with a flattened seam or a box pleat. For a flattened seam, the height of the gradient level must be at least 60 mm. Implementation of a gradient level with a box pleat requires a height of at least 80 mm.

          Simple Cross-Seam with Soldered on additional Binding Strips
  • Implementation from a roof slope of ≥ 10°
Externally, the simple cross-seam with soldered on additional binding strips functions like a simple cross-seam, but it offers additional protection against water collection for roof slope of at least 10°.
             
          Simple cross-seam
  • Implementation from a roof slope of ≥ 25°
The simple cross-seam can be used as a cross-join for roof slopes of ≥ 25°. The bottom course is hung, by the tilt-back, in the tilt-back of the top course. Unhindered change in course length due to temperature is to be taken care of in detail.