06 Roofing & Attic Ventilation

 

Introduction

This list of selections serves as a supplement to the Construction Documents (CD’s). Some of the selections below may be difficult to find or omitted on the CD’s. Check the CD’s for consistency with this list. Clarify with your contractor which document takes precedence for any inconsistencies.

 

Wood framed sloped roofs should serve the following primary functions:

1. Continuous bulk water drainage.
2. Continuous air barrier.
3. Control of moisture.
4. Continuous thermal layer.

 

Shingle Roofing

Asphalt shingles are used on most new homes in the U.S. for roof slopes greater than a 4:12 slope.  Alternatives to asphalt shingles include the following: wood shakes, wood shingles, slate, rubber shingles, fiberglass shingles and solar shingles.

 

Select shingle roofing material:

__ Asphalt shingle                   __ Wood shake                       __ Wood shingle

__ Rubber shingle                   __ Fiberglass shingle              __ Solar shingle

 

Consult the building code for restrictions on using shingle roofing on roof slopes lower than a 4:12 ratio.

 

Select Roofing Manufacturer/ Product Name / Color:

                                                                                                                                   

 

Metal Roofing

There are three common metal roofing materials: steel, aluminum and Galvalume.  Aluminum may be the better choice to resist salt spray in coastal regions.  There are two common profiles for metal roofing: standing seam and corrugated. Standing seam steel is typically available in 22 guage or 24 gauge. Corrugated steel can be fabricated from 26 gauge or 29 guage (higher the number the thinner it is) which makes it less expensive than Standing seam. Standing seam is considered more upscale and is more common on high-end homes. Some metal roofs require a minimum slope. Research which product is right for your home.

 

Other Roofing Materials:

Other roofing materials, often used on low slope roofs where asphalt shingles can’t be used, include EPDM, EPDM is a single ply synthetic membrane and also referred to as “rubber roofing.” SBS Modified Bitumen rolled asphalt roofing can also be installed on a low slope roof.

 

Indicate if you want to use any of the following roofing materials and make sure they are specified on the Construction Drawings:

Metal ___       EPDM ___       Rolled Asphalt ___

 

If using metal roof, select profile of metal roof

__ Standing Seam                               __ Currugated

 

Select Roofing Manufacturer/ Product Name / Color:

                                                                                                                                   

 

Roofing Underlayment

Roofing underlayment is a water-resistive barrier material installed above the roof sheathing and below the roofing material. The underlayment serves as an added layer of protection from severe weather. The type of underlayment may vary depending on which type of roofing material selected. If you select integrated sheathing (see section 04, Rough Framing), underlayment may not be required.

 

Select type of underlayment:

__ asphalt saturated felt (water resistive)

__ synthetic underlayment (water resistive)

__ rubberized asphalt underlayment (waterproof)

 

An Ice barrier may be required under your shingles depending on your climate zone. Select type of ice barrier under shingles:

__ at entire roof         __ at perimeter only               __ not used

 

Vented Attic

This is the most common type of wood framed sloped roof assembly:  the thermal, vapor and air barrier is along the flat ceiling surface below. The space between the sloped roof sheathing and the insulated ceiling below is effectively ventilated using a perforated soffit vent at the bottom of the roof and either a continuous ridge vent or several static area vents near the top of the roof. The continuous ridge vent is considered superior to the static area vents. However, if your roof design consists of a large “hip,” it may not be possible to incorporate a ridge vent. The ridge or static roof vents should be specified on the roof plan. Verify the type, number and location of these vents with your Architect and Builder.

 

Select type of roof vent:

__ Continuous ridge vent                    __ Static area vent

 

 

Unvented Attic

In some cases, an unventilated roof may be necessary. For instance, a sloped ceiling that is parallel to the roof plane, where the ceiling material is attached to the bottom of the rafters and the roof sheathing is attached to the top of the rafters. The control of moisture is challenging in an enclosed rafter assembly such as this. The type of insulation and moisture control strategy may vary depending on the climate zone you are in. Review this strategy with your Architect and Contractor prior to making final selections.

 

Accessories

Select color of Drip Edge: _____________________