Roof Rafters And Ceiling Joists

Rafter ties or ceiling joists acting as rafter ties are required by code unless the house is designed so that the walls or a structural ridge beam carries the full load of the roof.

Roof rafters and ceiling joists.

The are similar to trusses in this regard. Use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. The joists might then be covered with osb or plywood to form an attic floor for storage. Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall.

If you are framing a cathedral ceiling there are a couple ways to deal with the need for rafter ties. You can possibly remove them altogether of you include posts in the gable walls to support a structural ridge. In this design the tops of the rafters attach to a load bearing ridge beam that runs along the length of the roof. In unfinished space an attic insulation is typically laid between the joists.

A structural ridge is the standard alternative to ceiling joists. Corbett grace their parents and even their kids are learning a lot about the many ways a few right many wrong to build a high performance home. Assuming that your builders have chosen to use wood for your house s frame your roofing joists ceiling joists rafters or trusses will be made from long planks of wood placed parallel to one another at evenly spaced intervals along the length of your roof. Rafters form the foundation for attachment of the roof boards onto which the final roof covering is fixed.