How to Order Shingles and Accessories for a Complete Roof

Step by Step

1. 1Step 1: Start from total squares with waste

   If your roof measures 24 squares of sloped area and you add 12 percent for waste, you need about 27 squares of field shingle, which is 81 bundles at 3 bundles per square. Some supplier systems count in pallets: a typical pallet holds 42 bundles, or 14 squares, but check the product.

   If the roof has several pitches, total them separately. A low-slope section may need a different underlayment and the same shingle, so the shingle quantity can be combined but the underlayment quantity cannot.

2. 2Step 2: Choose the shingle, colour and lot

   Colours vary slightly between production runs, and on a large roof the difference can show as a patch. Ask the supplier to deliver all bundles from one lot and check the lot number printed on the wrapper. If you need to reorder mid-job, mix bundles from old and new lots across the roof rather than laying one lot on one slope.

   Stay within one manufacturer's system when you can. Manufacturers typically require their own starter, cap and underlayment products to qualify for the system warranty, and the wrapper lists what is required.

3. 3Step 3: Order starter strip by the linear foot

   Starter goes along the eaves and, for most products, up the rakes as well. Add both lengths from your report or sketch. A bundle of manufactured starter usually covers somewhere between 100 and 120 linear feet, but some are closer to 70 to 80, so check the wrapper.

   Add 5 to 10 percent for waste and cuts. The installation itself is covered in how to install starter strip shingles.

4. 4Step 4: Order hip and ridge cap from the ridge and hip length

   Hip and ridge cap is sold by the bundle, and coverage depends on the exposure and the product. A bundle covers roughly 20 to 35 linear feet. Dividing by the wrong figure is the most common cap mistake, and it is expensive, because cap is priced higher per square than field shingle.

   Add a few bundles for waste, especially in cold weather when caps crack while being bent. See how to install hip and ridge cap shingles.

   Tip: If the ridge will carry a continuous vent, the cap goes over it. Order a cap designed for the vent, or confirm the cap bundle's coverage over a vent.

5. 5Step 5: Order underlayment by roll coverage

   Synthetic underlayment rolls cover roughly 10 to 10.5 squares each after laps are allowed for. Felt rolls cover less. Confirm the coverage on the roll, and account for the extra coverage needed at laps, valleys and hips.

   Self-adhered ice and water shield goes along the eaves, in valleys, around penetrations and over low-slope sections. Measure those lengths and widths separately, and see how to install synthetic underlayment for the layout.

6. 6Step 6: Order drip edge, nails, vents and flashing

   Drip edge comes in 10 foot pieces: divide the eave and rake lengths by 9.5 to allow for laps. Roofing nails for the field are usually 1-1/4 inch galvanized coil nails, with longer nails for the cap and for roofs with existing layers or thick decking. A pound of 1-1/4 inch roofing nails is roughly 200 nails, so order extra so you never run out mid-roof.

   Count every vent, pipe, exhaust and chimney. Replace pipe boots and step flashing on every reroof, and size ventilation by the attic ventilation calculation rather than by habit.

7. 7Step 7: Plan delivery and ask for rooftop loading

   Many suppliers will boom or conveyor the bundles onto the roof for a fee. It saves hours of carrying and keeps the load spread in the way you ask. Tell them which slope you want loaded, and how many bundles per spot. The staging rules are in how to load and stage shingle bundles.

   If the roof is wet, loading bundles onto it will damage the wrapping and start the shingles sliding. Move the delivery to a dry window, and tarp bundles that will sit overnight.

8. 8Step 8: Check the delivery against the order

   Check every line on the delivery ticket against your order while the driver is still there. Shortages and damaged bundles are simple to fix in the first hour and awkward after you have started work.

   Store shingles flat on a dry, level surface, out of direct sun and off wet ground. Keep bundle stacks to the height the manufacturer allows, commonly no more than a few bundles high, and cover them with a breathable tarp.

Sample Material List for a 25 Square Roof

Common Mistakes

• Ordering field shingles only. Missing starter, cap or underlayment shuts a job down for a day.
• Using a generic bundle coverage number. Cap and starter bundles vary widely in linear coverage, and every product is different.
• Mixing colour lots across slopes. A visible colour change between two slopes is the usual result. Blend bundles across the whole roof.
• Forgetting delivery logistics. A boom truck needs room to stand and clearance from power lines, and a wet roof is a poor place to load bundles.
• Ignoring ventilation. Adding shingles to a poorly vented attic shortens their life. Size the vents in the same order.
• Not allowing for a short lot. Some colours are backordered, so order early when the roof is on a schedule.