Sunset Green Home's roofing subcontractor, J.P. Hunter Roofing, arrived on the scene yesterday! So over the coming weeks we will start to see the finished exterior of the house take form. I'll post updates as the work moves forward, but today's Progress Update focuses on Sunset Green Home’s strategy for creating a high performance, durable coastal roof. There are many possible high quality roof assemblies - ranging from ENERGY STAR rated asphalt to durable slate to metal roofing.
But one type of roof - natural cedar - is traditionally found in the coastal areas of Long Island. Sunset Green Home has elected to use a natural cedar roof on the main house (stay tuned for a post on the standing seam metal roof we're installing on the pool house). A natural cedar roof has the added benefit of being energy efficient and resistant to wind.
So what does Sunset Green Home’s roof assembly include?
I’ve written over the past few weeks about Huber Engineered Woods' ZIP System sheathing, and how it helps Sunset Green Home achieve an airtight shell (a “must” for a LEED certified home) and provides continuous sheathing required for wind-resistant construction. ZIP System sheathing is the base layer of Sunset Green Home’s roof system.
Ice & Water Shield
Grace Ice & Water Shield, a self-adhering rubberized asphalt underlayment is the next important layer, as it is “designed to protect homes from wind-driven rain and ice dams.” Installed at the most vulnerable areas of the roof (e.g., at the eaves, rakes and valleys), it helps to prevent ice damming and also forms a watertight seal around the nails that are used to adhere the roof shingles to the sheathing, thereby reducing the likelihood of a roof leak.
Lead coated copper flashing is another important roofing component and is used for its ability to hold up against the elements as well as its ability to be soldered. The product is used at the connection of the sloped roof to the sidewalls (with "step flashing" to the walls where the walls are terminated with "apron flashing"). It is also installed around the chimney area and is custom fabricated into roof boots for all plumbing vents that protrude through the roof.
Drainage Plane and Air Gap
Ventgrid12™ is the third underlayment on Sunset Green Home’s roof. Made of recycled - and recyclable - polyolefin, Ventgrid12™ is a rigid sheet in a 2” grid pattern that acts as a drainage plane and air gap between the roof deck and the roof shingles. According to Ventgrid, “the sun’s intensity has increased dramatically in recent years...as a result, unprecedented heat build-up commonly occurs between the shingles and the roof sheathing causing degradation in the form of splitting, cracking, curling, warping and cupping resulting in significant openings for water to pour in." In addition to providing an air gap for heat control, a "secondary benefit is the drainage plane that is formed by installing Ventgrid12™ behind the roofing materials, thereby creating another layer of protection for the structure itself.”
Sunset Green Home’s roof will be finished with SFI certified 5/8” thick taper sawn Western Red Cedar shingles from Anbrook Industries. The butts of taper sawn shingles are thicker than a 3/8” thick cedar perfection shingle, which is often used on a cedar roof. Because of its additional thickness, a taper sawn shingle will perform better when subjected to the sun’s UV rays and the moist weather conditions of Sunset Green Home’s coastal location.
In addition to their SFI certification, Anbrook’s shingles carry the “Certi” label, which indicates that the mill manufactures its products according to standards set by the Cedar Shake and Shingle Bureau (CSSB), a non-profit industry organization, and voluntarily submits to random inspections by agencies contracted by CSSB.
Stainless Steel Nails
The shingles will be attached to the rest of the roof assembly using Simpson Strong-Tie’s type 316 Stainless Steel nails, which resist corrosion and are manufactured especially for seaside applications.
Taken together, the elements of Sunset Green Home’s roof form a durable, energy efficient and environmentally friendly assembly – and a beautiful roof that Sunset Green Home will enjoy for many years to come.