J.T. Pennington - Week 8 Lessons Learned

Week 8 : October 18th - October 20th (Short week because of Clemson's academic fall break)

Lessons learned/reflections: I started and completed a roof plan for a private residence in Sullivan's Island this week, and I thought about it differently from how I have ever made a roof plan drawing in the past.

My previous experience - largely with commercial work - has been setting the roof eave distance from face of structural wall out the depth of the structural overhang - and knowing the pitch of the roof that was desired, and the geometry raised to the ridge condition and the lines extended to become whatever they needed to be; most of the commercial buildings had raised parapets where the roof was lower than what was shown from the exterior elevations and was often a large shed roof with hidden roof top mechanical equipment while the lower edge of the roof had thru-wall scuppers, collection heads, and downspouts- or a combination of that perimeter condition with secondary roof drains (+4" max above the primary drain) or a thru-wall drain with a lamb's tongue or overflow device that was daylit to curb. The wall lamb's tongue was the signal to building owner's and maintenance that the roof drain was clogged with leaves and the roof needed some maintenance attention.

Working with Beau Clowney Architects' for this residential project, I instead marked the exterior wall outer and inner face of stud condition and knew the distance of the eave or rafter tail overhang distance for the aesthetic condition that we wanted and drew and pulled lines from a combination of section and elevation overlays. The tricky part was where the shed roofs had crickets or met raised tower elements - and how different angled 3:12 shed roof and 4:12 tower pitches met at a diagonal angle. One of the things I thought of while driving down the highway is these residences don't have downspouts and I didn't have to do any roof calculations for gutter and downspout sizings because the water drained directly to the pervious adjacent area on the site.

Images of work completed:

Front elevation - notice the complexity of the tower elements on the symmetrical facade and how each of those have a different slope of rafter tails at the end - the second floor over the entry has a 3:12 shed roof which on the left side of the house the eave conditions match for a continuous corner - but the right side of the house is taller - it is similar, but different.

Roof plan sketch - the roof was so complicated to me with tower elements and different pitches that I sketched it out with my hand before I even started; I really like the dormer elements over the office and rear master bathroom and guest bedroom. They look really nice on the exterior elevations.

Roof plan drawing