Gable Roof No Ceiling Joists

At gable end truss.

Gable roof no ceiling joists.

Someone with more knowledge please correct me if i m wrong. If you are framing a cathedral ceiling there are a couple ways to deal with the need for rafter ties. Can i raise the ceiling joists to create the vaulted ceiling. Yes you can raise the ceiling joists but with restrictions.

The thrust to worry about is at the tails of the common rafters. The shape and size of a roof depends on the span and the floor plan of the building. If you build a square hip roof you can do it without ceiling joists. Without it the weight on the roof will cause the rafters to flatten particularly at the center of the span and bow the wall out where the rafters connect to the wall plate and ultimately fail.

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. A gable roof consists of two upward sloping sides that slope at the same angle and from the end look like a symmetrical triangle. And the roof covering material determines the size cross section area of the roofing timbers used. Table r802 4 1 ceiling joist spans for common lumber species uninhabitable attics without storage live load 10 psf l δ 240.

The most common tension tie observed in roof framing for a conventionally framed gable roof is the ceiling joist that forms the bottom chord of the roof triangle shown below. If you remove the ceiling joists its like removing the bottom leg of a triangle. Gable roofs without ceiling joists provide a much higher and triangular shaped ceiling inside the home. A client wants to create a vaulted ceiling in an addition with a shallow 4 12 pitch roof the rafters are 16 inches o c with no 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. Ceiling joist or roof truss to top track of bearing wall b. The sheathing top plates hold the corners together. 10 screws in accordance with table r804 3 1 1 3 evenly spaced not less than 1 2 from all edges.

For other grades and species and for other loading conditions refer to the awc stjr. Darren tracy pe owner of west branch engineering in saratoga springs n y responds. A gable roof is a heavy structure and if you want to prevent your roof from collapsing you ll have to frame the structure correctly. By fastening the lower rafter ends to the horizontal ceiling joist and the upper rafter ends to the ridge board or to one another in older framing the triangular.

Gable end truss to end wall top track. Spans for ceiling joists shall be in accordance with tables r802 4 1 and r802 4 2. Rafter to ceiling joist.