Sika Limited has recently undertaken a review of its guidance concerning mechanically fixed and adhered upstands, i.e. the vertical elements of the roof. This review has resulted in a series of important updates to the standard guidance, which all roofing professionals should be fully aware of, and which we will be adhering to, here at Enviroply Roofing.
Why is the guidance for upstands being updated?
In recent years, the roofing industry has undergone several notable changes. In response, Sika now has an ideal opportunity to refine its approach to single-ply membrane upstands and to establish clear, consistent guidance on this topic. The updated policies and guidance are intended to promote a uniform and robust methodology, ultimately supporting optimal performance throughout the entire design life.
Some of the changes that have fuelled this update include:
- The current range of single-ply membranes (now streamlined to include only Sikaplan® PVC and Sarnafil® AT) has been significantly simplified, rendering many of the older installation methods largely obsolete.
- An increased use of non-combustible cement-particle type boards in parapet/upstand construction.
- Technical guidance from trade bodies recommends that the maximum height of an upstand should ideally not exceed 1100mm; however, it is acknowledged that certain design scenarios may necessitate exceeding this limit.
What are the key aspects of the updated guidance?
Sika have issued new advice for adhered upstands, self adhesive upstands, and mechanically fixed upstands.
Adhered upstands – Sikaplan® SG
When an upstand detail exceeds 500mm in height, the membrane must be supported with additional intermediate mechanical restraint, such as S-Bar/Peelstop or washers. Further restraint should be introduced at every subsequent 500mm increment.
Sika Sarnafil® AT P FSA (self-adhesive detail membrane)
All upstands, regardless of height, must be primed with Sika Primer 600 or 610. For upstand details exceeding 800mm in height, additional intermediate mechanical restraint (such as S-Bar, Peelstop, or washers) is required. Further restraint should be applied at every additional 800mm increment.
Mechanically fixed upstands – Sikaplan® G or Sarnafil® AT
Upstands measuring less than 800mm in height may continue to follow current mechanical fixation guidance: secured at the top with a weld or restraint, and at the base using an S-Bar welded to the field sheet with a cover strap.
For upstands exceeding 800mm but remaining below 2 metres, additional in-seam fixation is required.
Where upstands exceed 2 metres in height, intermediate mechanical restraint (such as S-Bar or washers) must also be incorporated.
Implementation of new guidance
All specifications are now issued in accordance with the updated upstand guidance outlined above. To ensure compliance with guarantee requirements, all on-site installations must reflect these revised instructions as specified.
If you have any questions about these updates, Sika asks that you contact your local Site Support Engineer for any additional clarity and practical guidance.