❄ A large ‘Scotch’ at Christmas

Pretty apt for this time of year, however I’m not talking about whisky. I’ve just finished raising this pretty neat little barn in the garden of a property which was elegantly extended in 2015!

View from garden
View from barn

The term ‘scotch’ refers to a type of housing joint that is traditionally used for rafter feet (the bottom end!). I decided to use this type of joint to support the primary rafters as the frame design is what’s known as a ‘reversed assembly’, which I will try and explain.

Typically a traditional oak frame has the tie beam sitting on top of the wall plate, secured using a simple dovetail joint, like so:

Traditional dovetail joint between wall plate and tie beam.

The following exploded view illustrates the joints used in this reversed assembly design. The primary rafter is diminished and housed into an appropriate scotch pocket. The dovetail joint is inverted, and in this case also set down to allow for a higher tie beam. A simple mortice and tenon for post and tie beam connection.

Reversed assembly, with scotched primary rafter.

The reason for this reversed assembly was to keep the primary rafters in the same alignment at the common rafters, allowing them to project past the wall plate. The design breif was to be minimilist, no curved or unnesessary timbers, maintaining simple clean lines throughout. Here it is assembled:

Awful pictures I know, it is a rainy December in muddy Suffolk! This frame is to be tiled with reclaimed plain / peg tiles, with no membrane and sweet chestnut tile batten it should look supurb. I will return to take some better pictures when complete.

Can you see the slip tenon in the ridge beam?