#ONTARIO BUILDING CODE JACK STUD WINDOWS#

Are there any available lumber strength tables to determine maximum span for studs, joists, and rafters? I know white pine is not a preferred species for stick framing, but I have an abundance of good quality white pine and it is easy to work with.

If the opening is 5 feet wide and youРІР‚в„ўve taken out four studs, add two studs to the assembly on each side.I would like to use white pine for framing lumber for a house. A good rule of thumb is to add an extra stud to each jamb stud assembly for every two studs that are removed for the window. In some cases, we call for engineered-lumber posts with proper connection hardware to help transfer the forces. In high-wind areas like the coast where I work, we often beef up the jack-stud assembly by installing additional king studs to form a stronger jamb assembly. When jacks are split, they cannot help to resist those transverse loads, which then become concentrated mainly on the king studs. The studs at the sides of the opening are doing the work of three or four studs missing from the opening. Those loads become concentrated at the king-and-jack-stud assembly. Think of it this way: When the common studs are removed to create an opening, king studs and jacks are asked to assume the loads that would normally be resisted by the common studs. On smaller openings, a single king stud and continuous jack stud are usually OK, but for larger openings, more than one king stud may be required. At window and door openings, the common stud spacing is interrupted, and the wind pressure on the window is transmitted to the structural elements around all four sides of the rough opening. This transfer occurs in bending along the strong axis of the studs and into the deck above and below. In a framed wall, the studs act in concert with the cladding system, transferring horizontal wind forces into the horizontal floor and roof diaphragms. When youРІР‚в„ўre analyzing jack requirements, this second type of loading is most relevant. This loading is transferred into the structural frame in two directions: longitudinally, or parallel to the wall (when acting as a shear wall), and transversely, or perpendicular to the wall, when lateral loads are applied against the wall area (as with a sail).

Keep in mind that the stud wall assembly is also important for resisting lateral (wind or seismic) loads.

#ONTARIO BUILDING CODE JACK STUD WINDOWS#

When the wood shrank across its thickness, the loads from above reportedly caused the opening to rack and the windows to bind.Р”В«ut a window that operates poorly is just a small part of why split jacks arenРІР‚в„ўt a good idea. Anecdotally, I have heard of framers who used the split-jamb method with green wood. If youРІР‚в„ўve framed the walls with good kiln-dried lumber, transferring those vertical loads with split jacks should not be a problem structurally. Most people think only in terms of the gravity load transfer-that is, floor and roof loads transmitted through the header and into the king-and-jack-stud assembly. While not calling out solid jacks specifically, it clearly shows the jacks running in an uninterrupted line from the header to the bottom plate, with the sill butting into the jacks on both sides. This illustration is how the IRC presents wall framing. While the code does not directly address the issue of split jacks, section R602.3 Design and Construction does demonstrate how rough openings for windows should be framed: РІР‚СљExterior walls of wood-frame construction shall be designed and constructed in accordance with the provisions of this chapter and Figures R602.3(1) and R602.3(2), or in accordance with AWC NDS.РІР‚Сњ Figure R602.3(2) (re-created below) clearly shows solid jacks (or 'trimmers,' as they are commonly called on the West coast) on either side of a framed window opening, with the sill butting into the jacks. John Bologna, a structural engineer and president of Coastal Engineering Co., in Orleans, Mass., responds: When the jacks on a window opening are interrupted at the sill, that framing strategy is known as the РІР‚Сљsplit-jackРІР‚Сњ or РІР‚Сљsplit-jambРІР‚Сњ method, and the short answer to your question is that split jacks are structurally weaker than solid jacks.Р”В¬ode considerations. Is there a structural difference between full-height jacks at window openings and split jacks that fit around the rough sill?Р”Р„.

Ontario building code jack stud