Under a prescriptive building code like the IRC, the elements of a building are structural to transmit the forces from the exterior (high winds, seismic, etc.). These structural products; plates, studs, joists, rafters, sheathing (wall, roof, floor) are all rated for their span, shear, etc. Other elements are not structural; most sidings, carpets, interior/exterior trim, roofing, etc., that don’t contribute to the buildings strength or transmit these outside forces to the ground. An interior structural wall carrying a roof load would need full contact with the structural sheathing on the floor below. An exterior over-frame roof wood member is structural and needs the contact to another structurally-rated material below it to transmit; Chapter 8---shall control the design and const. of roof/ceiling
system for all buildings; http://publicecodes.citation.com/ico...9_8_sec001.htm
The next section http://publicecodes.citation.com/ico...001_par001.htm
under requirements--- capable of accommodating/transmitting the resulting loads to supporting structural elements.
(Refers us to); http://publicecodes.citation.com/ico...9_3_sec001.htm
and lists the seven loads from point of origin through the load-resisting elements
to the foundation.
Load-bearing lumber requires a grade mark
or C of I on rafters, trusses, and ceiling joists; http://publicecodes.citation.com/ico...9_8_sec002.htm
“Wood Roof Framing”- http://publicecodes.citation.com/ico...002_par016.htm
3/12 min. slope, components fastened per Table 602.3.1; Under “ROOF
” Items 1-6; rafter, ceiling joist, blocking, collar tie, no roof shingles listed
- as they are not structural; http://publicecodes.citation.com/ico...002_par005.htm
The only alternate material used is on modular homes- when ceiling is pre attached- requires a “compression strip” that shall be of a material capable of transmitting the loads transferred through it
Asphalt roofing is found in chapter 9 (claddings), not 8 (roof members); “Requirements For Roof Coverings” installed to resist the component and cladding loads
…… high-winds, tall building, and seismic loads, not structural loads to the foundation. Remove the asphalt shingles (roof cladding) under a load-bearing roof/ceiling system, remove the carpet/pad (floor cladding) under a load-bearing wall, remove the siding (wall cladding) between the old/new wall connection to get shear-flow for lateral resistance, as per minimum Code (a “D” on a school test, passing, but barely).
I agree on the drive-in latches, though I’ve yet to replace one because they failed (turned-rotated, or come loose) because they are locked-in by the lock-set. Usually the whole door-l.s., hinges and jambs are up-graded with a new pre-hung unit.