Roofing and Insulation Supplies Guide: Shingles, Sealants, Spray Foam and R-Values

Roofing and insulation jobs succeed or fail on planning. Ordering too few bundles stalls a crew. Choosing the wrong foam or R-value leads to callbacks and higher energy bills. This guide explains how to estimate shingles, choose sealants and foam, pick insulation R-values and keep crews safe on the roof.

Roofing basics

Shingle types

Three-tab shingles are flat and economical. Architectural (laminated or dimensional) shingles are thicker, have a layered look and usually carry stronger wind ratings and longer limited warranties from the manufacturer. Most residential reroofs today use architectural shingles.

Estimating materials

1. Measure the length and width of each roof plane and multiply to get square feet.
2. Divide the total by 100 to get squares.
3. Multiply by the bundles per square, usually three for architectural shingles.
4. Add 10 percent waste for simple gable roofs and 15 percent or more for hips, valleys and dormers.
5. Add starter strip for eaves and rakes, and hip and ridge cap by linear foot.

The parts beyond shingles

• Underlayment: synthetic underlayment over the deck, plus ice and water shield at eaves and valleys in cold climates.
• Drip edge and flashing: at eaves, rakes, walls, chimneys and skylights.
• Ventilation: balanced intake (soffit) and exhaust (ridge or roof vents) to control heat and moisture.
• Fasteners: roofing nails of the right length to penetrate the deck, placed per the shingle manufacturer's pattern.
• Sealants: roofing cement or silicone roof sealant for flashing details and small repairs.

Choosing a roof sealant

Asphalt roofing cement is the traditional choice for sealing shingle tabs and flashing edges. Silicone roof sealants stay flexible, resist UV and handle ponding water well, which makes them popular for metal and low-slope repairs. Most silicone products should not go over old asphalt coatings without the primer the manufacturer specifies, so read the label for compatible surfaces and cure times. For any repair, clean and dry the surface first and apply sealant in mild weather.

Spray foam and sealants

Straw foam vs gun foam

Straw-applied cans are fine for occasional gaps. Gun foam uses a reusable applicator gun, gives more control, wastes less and lets you stop and start without the can clogging. Contractors usually buy gun foam by the case.

Choose the right formula

• Gaps and cracks: standard expanding foam for sill plates, rim joists and penetrations.
• Windows and doors: low-expansion foam that will not bow frames.
• Fire blocking: fire-rated, colored foam where code requires fire blocking between floors and walls.

Clean foam guns with the matching cleaner, and store cans within the temperature range on the label.

Insulation and R-values

What R-value means

R-value measures resistance to heat flow. Higher is better, but it only works if the insulation fills the cavity without compressing it and the air leaks are sealed first.

Typical targets

• 2x4 walls: R-13 to R-15 batts.
• 2x6 walls: R-19 to R-21 batts.
• Floors over unheated spaces: often R-19 to R-30.
• Attics: roughly R-30 to R-60 depending on climate zone, usually with blown loose-fill.

Faced vs unfaced

Kraft-faced batts include a vapor retarder for the warm-in-winter side of walls in many climates. Unfaced batts are used where a separate vapor control layer exists, when adding layers over existing insulation, or in floors and interior walls for sound. Follow your local code.

Loose-fill

Blown fiberglass or cellulose fills attics quickly and covers irregular framing. Use rulers or depth markers to confirm the installed depth matches the bag chart for your R-value.

Roof safety

Falls are the leading cause of death in construction. OSHA generally requires fall protection at 6 feet or more for construction work. Use a full-body harness, a shock-absorbing lanyard or self-retracting lifeline and a rated roof anchor, and inspect gear before each use. Add eye protection when cutting and nailing, and keep ladders secured and extended above the roof edge.

Common mistakes to avoid

• Forgetting waste, starter strip and ridge cap in the shingle order.
• Blocking soffit vents with insulation. Use baffles to keep air moving.
• Compressing batts into cavities that are too shallow, which lowers the R-value.
• Using high-expansion foam around windows and doors.
• Working on a roof without a fall protection plan.

Products to compare on shopmanu.com

These supplies come from our partner Roofing4US, which stocks contractor quantities. Check each listing for color options, case counts and coverage.

• Landmark Shingles (1 Bundle - 33.3 Sq Ft) - All Colors — architectural shingles sold by the bundle (33.3 sq ft each)
• IKO Dynasty Hip & Ridge Shingle (1 Bundle - 36.5 Lin Ft) - Glacier — hip and ridge cap shingles
• Knauf Ecoroll R-19 Unfaced Fiberglass Insulation Roll 6.25 in x 15 in x 39.2 ft (6 Rolls) — R-19 unfaced fiberglass rolls for 2x6 framing and floors
• Owens Corning PROPINK L77 PINK Fiberglas Unbonded Loosefill Insulation — loose-fill fiberglass for blown attic insulation
• HandiFoam Gun Foam Sealant 24 Oz (680G)(12 cans per case) — a case of gun-applied foam sealant
• CONVERTIBLE FOAM GUN (Can+Cylinder) 13 Inch with Teflon Seat — a convertible foam gun for can and cylinder foam
• 12 oz Handi Foam Fireblock Straw — fire-blocking foam sealant
• All Purpose Flex Repair 100% Silicone Roof Sealant - 1 Gallon — a silicone roof repair sealant

Ordering, shipping and returns

Manu is the seller of record for every order placed on shopmanu.com, and we are your first point of contact for any question about an order. The shipping charge is calculated and shown at checkout before you pay, and delivery dates are estimates rather than guarantees. Full details are in our Shipping Policy.

Items shipped by a partner supplier (the product page lists a vendor other than "Manu") are fulfilled directly by that independent supplier. The supplier sets the processing time, and its shipping rate for that line item appears at checkout. Returns on these items can follow the supplier's process, including the return address and whether a label is provided, so please contact us before you ship anything back. We will confirm in writing which process applies and what, if anything, return shipping will cost you.

The Return & Refund Policy lists the full conditions and the categories that are not returnable. If you are unsure whether something fits your application, ask us before you order: email info@meetmanu.com or call (210) 857-3040.

Frequently asked questions

How many bundles of shingles do I need?

Roofing is measured in squares, where one square equals 100 square feet. Most architectural shingles come three bundles to a square, about 33.3 square feet per bundle. Measure each roof plane, add them up, then add roughly 10 to 15 percent for waste, plus starter strip and ridge cap.

What R-value do I need in my attic?

The U.S. Department of Energy recommends about R-30 to R-49 for attics in the warmest zones and up to R-49 to R-60 in colder zones. Check the recommendation for your climate zone and your local energy code.

What is fireblock foam used for?

Fireblock foam is a colored, fire-rated sealant used to seal penetrations for pipes, wires and vents between floors and walls where building codes require fire blocking. Check local code for where it is accepted.

Can I use regular spray foam around windows?

Use a low-expansion foam made for windows and doors. High-expansion foam can bow frames and make windows and doors stick.

Do I need fall protection on a residential roof?

OSHA generally requires fall protection for construction work at 6 feet or more above a lower level, including residential roofing. A harness, lanyard or lifeline and a proper roof anchor are the standard setup.