How is the upper end of a form for a concrete wall typically attached?

In concrete formwork, the upper end of a form for a concrete wall is typically attached to the walers. Walers are horizontal members that support the vertical form panels during concrete placement. They provide the necessary stability and help distribute the pressure exerted by the wet concrete, ensuring the formwork remains secure and does not deform under load.

The use of walers is essential because they also help to maintain the alignment of the forms, ensuring that the wall is constructed to the correct dimensions and specifications. Their design allows them to resist bending and buckling, which is crucial given the substantial forces involved in pouring concrete.

While other options may refer to structural components, they do not serve the same specific function as walers in the context of formwork for concrete walls. Studs generally support wall assemblies but are not typically involved in the formwork system for pouring concrete. Nails are used as fasteners but do not provide the required support or alignment on their own. Beams are structural elements but are not the main attachment points for the upper end of concrete formwork.