Timber Connection Design Guides
Practical notes on timber connection design - the principles behind the standards, the failure modes that matter, and the detailing decisions that bite you in practice.
Timber Connection Design
An EC5 overview of timber connection design - fastener categories, failure modes, geometry rules, and the principles that govern lateral and moment-resisting connections.
Bolts in Timber Connections
How bolts actually carry load in timber - the bearing mechanism, the yield moment, the washer rule, the rope effect, and the pre-tensioning myth that gets engineers in trouble.
Dowels in Timber Connections
What makes a dowel different from a bolt - the tight-fit hole, the absence of slip, the lack of rope effect, and why dowels dominate moment connections and exposed timber frames.
Bolts vs Dowels: Choosing the Fastener
Bolts and dowels look almost identical but EC5 treats them differently. A head-to-head on slip, capacity, spacing, fire, and buildability - and a simple framework for choosing between them.
The Rope Effect Explained
Eurocode 5 lets a bolt carry up to 25% more lateral load through the so-called rope effect. It is not friction, not pre-tension, and not magic - it is the bolt acting as a tie. Here is what is actually happening, and why it matters.
Moment-Resisting Timber Connections
How a bolt or dowel group carries moment in a timber connection to EC5 - the rigid-joint principle, the polar moment method, why bolt spacing (not position) drives efficiency, and a full worked eaves-connection example.
Why TRADA's connection tools disagree with EC5:2004 - a worked comparison
The TRADA v2.04 Joint Designer still matches EC5 for timber-to-timber but over-predicts steel-to-timber capacity by roughly 50% - the three ENV-to-EN 1995-1-1:2004 changes behind the gap, shown with full working for an M12 bolt.