Title: How to Cut a Birdsmouth Joint | Fixing Rafters and Joists to Wall Plates | DIY Doctor
Headings: Birdsmouth Joint – How to Cut a Birdsmouth and how to Cut and Install Roofing Rafters and Joists
Birdsmouth Joint – How to Cut a Birdsmouth and how to Cut and Install Roofing Rafters and Joists
What is a Birdsmouth joint or Cut?
How and Where is a Birdsmouth Cut Used?
How to Cut a Birdsmouth Joint
Calculating the Pitch of a Roof and Making Ridge Cut
Calculate Rafter or Joist Length to Birdsmouth Location
Making a Birdsmouth Joint
Making the Tail Cut

Content: How to Cut a Birdsmouth Joint | Fixing Rafters and Joists to Wall Plates | DIY Doctor
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Birdsmouth Joint – How to Cut a Birdsmouth and how to Cut and Install Roofing Rafters and Joists
In this DIY guide you will learn how to install a roofing joist or rafter that includes how to work out the pitch of a roof, cut a ridge or plumb cut at the correct angle, work out the correct length of joist you need and the exact location for a birds mouth joint, how to correctly cut a birds mouth joint and finally how to cut a tail cut to finish off the end of a roofing joist. Don't want to do this job yourself? Let us help you find a tradesman local to you
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Unless you are a seasoned carpenter or a keen DIY’er, you will probably never have come across a birdsmouth joint before so will be unfamiliar with how this particular woodworking joint is used in roof construction and also in building fences. If you are indeed looking to construct a pitched roof of some kind for a self build project home or even a garden shed or outbuilding you are going to need to cut all of your rafters or roofing joists to fit. The best and strongest way to do this is by using a Birdsmouth joint. What is a Birdsmouth joint or Cut? The Birdsmouth Joint (also called the birds beak cut or birds beak joint) is a small triangular shaped cut out at the base of a roofing joist that allows the joist to sit nicely on top of the wall plate (top of the wall before the roof starts). As I’m sure you have gathered, the name “Birdsmouth Joint” refers to the fact that the joint itself looks a little like a birdsmouth when viewed from the side. Birdsmouth joints cut into roofing rafters and mounted in place on top of the wall plate
If is wasn’t for this joint, a rafter or roofing joist would only balance on top of the wall plate, making fixing difficult not to mention the fact that there wouldn’t be any solid connection between the roof and the supporting walls below. The addition of this joint allows the top of the rafter to sit solidly down on top of the horizontal area of the plate, whilst the vertical front edge butts up to the vertical exterior side edge of the wall plate.