Hard to tell. It looks very likely that what you see is lightweight plasterboard finishes hiding a structural steel or concrete beam. If this is the case you may struggle to get a satisfactory, sturdy fixing.
Does it sound solid when you tap it? If you are lucky the beam might be solid timber in which case it will be sturdy enough to fix to.
Fixing to the wall above the door opening visible in one of the photos may be an easier option. There is almost certainly a timber studs in that wall that a piece of sheet plywood (say 18mm thick) could be fixed to with big screw nails; your fingerboard would then be screwed onto the plywood.
Thanks. Yeah I've read up that method but as I don't own a stud finder I thought a beam might have been easier. I see now that perhaps that isn't the case!
A combined stud / pipe / cable finder can cost as little as £20. Small change if you accidentally drill or screw into a water / gas pipe or an electric cable. Unless you are absolutely sure what’s behind I wouldn’t drill / screw without checking.
Press Release Alpkit and Outside Bank Holiday Hathersage Tent Show 4-5th May
Gear News The Art of Climbing – Out Now
Podcast Mountain Air - 1. Sibusiso Vilane, First Black African on the Roof of the World
Fri Night Vid Finding Focus - Life Behind The Lens of a Climbing Photographer
This week's Friday Night Video is a portrait of a prolific climbing photographer from Wedge Climbing. Sam Pratt is well known in both the outdoor and competition scene but if you haven't heard of him, you've likely seen...