Quick answer: A square of shingles covers 100 square feet of roof. The shingles alone cost about $90 to $300 per square depending on the type. Fully installed with labor, tear-off, underlayment, and cleanup, most homeowners pay $450 to $850 per square nationally, and often $650 to $1,050 per square in higher-cost areas like the Portland metro, including Sandy, Oregon.
If you’ve been searching for this answer and keep finding numbers that don’t match, you’re not doing anything wrong. Most cost guides mix up three different “prices per square.” This guide separates them, shows you the math behind your roof size, and explains how to read a roofing quote so you know whether it’s fair.
What Is a Square of Shingles?
In roofing, a “square” is simply a unit of area equal to 100 square feet of roof surface. Roofers use it the way a flooring installer uses square feet: it makes measuring and pricing faster.
So when a contractor says your house has a “25-square roof,” they mean the roof surface is about 2,500 square feet. That’s the actual sloped surface of the roof, not the floor space inside your home. That difference matters a lot, and we’ll come back to it.
Is a Square of Shingles 10×10?
Yes, in area. A 10-foot by 10-foot section equals 100 square feet, which is one square. But a square doesn’t have to be shaped like a 10×10 box. A strip that’s 5 feet by 20 feet is also one square. It’s a measurement of area, not shape.
How Many Bundles Are in a Square?
Most asphalt shingles are packed three bundles per square, so each bundle covers about 33.3 square feet. Some heavier premium or designer shingles are packed four or even five bundles per square, so always check the wrapper. Each bundle typically weighs 60 to 80 pounds, which is why a full square of architectural shingles can weigh well over 200 pounds.
The Three “Prices Per Square” (Why Online Numbers Don’t Match)
This is the part most cost guides skip. When someone tells you what a square of shingles costs, they could mean any of these:
| What’s included | Typical price per square | Who uses this number |
|---|---|---|
| Shingles only (the bundles) | $90 – $300 | Supply stores, DIYers |
| All roofing materials (shingles, underlayment, starter, ridge cap, nails, drip edge, vents) | $200 – $450 | Contractors pricing a job |
| Fully installed (materials + labor + tear-off + disposal + cleanup) | $450 – $1,050+ | What homeowners actually pay |
When you see one website say “$120 a square” and another say “$800 a square,” both can be right. They’re just describing different things.
Shingle Material Cost by Type
| Shingle type | Material cost per square | Notes |
|---|---|---|
| 3-tab asphalt | ~$90 – $110 | Flat look, lower wind rating, being phased out by many brands |
| Architectural (dimensional) | ~$110 – $160 | Most common today; better look and wind resistance |
| Impact-resistant (Class 4) | ~$150 – $220 | Better for hail areas; may lower insurance premiums |
| Premium / designer | ~$200 – $300+ | Mimics slate or cedar; heavier; often 4–5 bundles per square |
One 2026 cost guide puts a bundle of 3-tab at about $30 and architectural at about $40, which works out to roughly $90 and $120 per square for shingles alone. Prices shift with region, brand, and supplier, so treat these as ballpark figures.
How Much Does 1 Square of Shingles Cost Installed?
Nationally, most contractors charge between $450 and $850 per square to install or replace an asphalt shingle roof on a typical house. In expensive markets, including Seattle, Portland, and other large coastal cities, quoted prices can run $650 to $1,050 per square.
Here’s roughly how an installed price per square breaks down on a standard replacement:
- Labor is the biggest share, often around half to 60% of the total.
- Materials (shingles plus all the accessories) make up most of the rest.
- Tear-off and disposal depend on how many old layers you have and local dump fees.
- Overhead, permits, and insurance for a licensed contractor make up the remainder.
Why the Same Roof Costs More in Some Places
Homeowners on roofing forums are often shocked by regional gaps. A 25-square roof that one roofer in Texas might do for under $10,000 can cost $15,000 to $20,000 in New England or the Northwest. That isn’t always overcharging. Northern and wetter climates usually require more ice and water shield, stricter code details, higher labor rates, and higher disposal fees.
For our area, This Old House notes that Oregon’s median home size of 1,946 square feet translates to about 19.5 roofing squares, and Sandy-area roofs face over 200 rainy days a year, moss pressure, and occasional snow loads. Those conditions call for good underlayment, proper ventilation, and algae-resistant shingles, which all affect the price per square.
How to Figure Out How Many Squares Your Roof Has
Here’s where many homeowners get tripped up: your home’s square footage is not your roof’s square footage. A sloped roof has more surface than the floor beneath it, plus overhangs that extend past the walls.
Step 1: Start With the Footprint
Measure the length and width of the house at the roof edge (including overhangs), or use your floor plan plus about a foot of overhang on each side.
Step 2: Multiply by the Pitch Factor
Roof pitch is how many inches the roof rises for every 12 inches across. Steeper roofs have more surface area.
| Roof pitch | Multiplier |
|---|---|
| 4/12 (low slope) | 1.054 |
| 6/12 (common) | 1.118 |
| 8/12 | 1.202 |
| 10/12 | 1.302 |
| 12/12 (steep) | 1.414 |
Step 3: Divide by 100
That gives you your measured roof squares.
Step 4: Add Waste
Shingles get cut at valleys, hips, rakes, and edges. Add about 10% for a simple gable roof and 15% or more for a hip roof or a roof with many valleys and dormers.
Worked Example
Say you have a single-story ranch home with a 1,500 sq ft footprint (including overhangs) and a 6/12 gable roof:
- 1,500 × 1.118 = 1,677 sq ft of roof surface
- 1,677 ÷ 100 = about 16.8 squares measured
- Add 10% waste = about 18.5 squares of material ordered
- At $650–$950 per square installed (a realistic range for our region), your roof would land roughly $10,900 to $16,000, before extras like decking replacement.
Measured Squares vs. Ordered Squares: Ask Your Roofer
This is a hidden reason bids don’t line up. Some contractors multiply their price by the measured roof squares and build waste into the rate. Others multiply by the ordered squares including waste. Neither is wrong, but if one bid says “17 squares” and another says “20 squares,” you need to know which method each used before comparing totals.
How to Read a Roofing Quote Line by Line
A fair quote should spell out more than one big number. Here’s what to look for:
- Number of squares, and whether it includes waste.
- Shingle brand and product line (for example, an architectural line versus a 3-tab line).
- Tear-off, including how many layers. A second layer usually costs extra.
- Decking replacement, usually priced per 4×8 sheet. On forums, homeowners report quotes ranging from about $50 to $125 per sheet installed depending on the market. Ask whether the price is an allowance, and how many sheets are assumed.
- Underlayment type, ideally synthetic.
- Ice and water shield, and where it goes (valleys, eaves, around penetrations).
- Drip edge, starter strip, and ridge cap.
- Flashing at chimneys, walls, and skylights. Is the old flashing reused or replaced?
- Ventilation, such as ridge vents or box vents.
- Pipe boots and penetrations.
- Permit, cleanup, and disposal.
- Workmanship warranty, separate from the manufacturer’s shingle warranty.
If a quote is missing most of these, ask for a full breakdown. A professional roofer won’t mind.
Is $20,000 for a 25-Square Roof Fair?
That works out to $800 per square. In a high-cost market, with full decking replacement, two layers of tear-off, and a lot of ice and water shield, it can be reasonable. If it’s just new shingles over solid decking on a simple roof, it’s on the high side. The only way to know is to compare line-item quotes from two or three licensed contractors.
People Also Ask: Quick Answers
How much does 1 square of roofing shingles cover?
One square covers 100 square feet of roof surface. With standard asphalt shingles, that’s three bundles. Remember to add 10–15% for waste when buying material.
Is a square of shingles 10×10?
Yes, a 10×10 area is exactly one square (100 square feet). The area just doesn’t have to be square-shaped.
How much does 1 square of shingles cost?
Shingles alone run about $90 to $300 per square depending on type. Installed, expect roughly $450 to $850 per square nationally, and $650 to $1,050 in higher-cost markets like the Portland area.
How much would shingles on a roof cost on 1,200 sq ft?
If 1,200 sq ft is your actual roof surface, that’s 12 squares, or about 13 to 14 squares with waste. Shingles alone would cost about $1,200 to $2,000 for architectural grade. A full installed replacement would typically run around $5,500 to $12,500 depending on region and roof condition. If 1,200 sq ft is your house size, your roof is likely 1,400 to 1,600 sq ft after pitch and overhangs, so budget accordingly.
How many bundles of shingles does it take to do a 20×20 roof?
A flat 20×20 area is 400 sq ft, or 4 squares, which is 12 bundles. Add 10–15% for waste and you’ll need about 14 bundles, plus starter strip and ridge cap. If 20×20 is the footprint of a pitched garage, measure the actual slope or apply the pitch multiplier, since a 6/12 roof on that footprint (with overhangs) can easily need 16 or more bundles.
What is the 25 rule in roofing?
The “25% rule” is a building code provision used in many areas. It says that if more than 25% of a roof is repaired or replaced within a 12-month period, the entire roof must be brought up to current code, which often means a full replacement. Codes vary by state and local jurisdiction, and some states have changed their rules in recent years, so check with your local building department. This rule often comes up in insurance claims. (See our guide on getting insurance to pay for a roof replacement in Oregon.)
How many bundles of shingles for a 1,500 sq ft roof?
A 1,500 sq ft roof surface is 15 squares, which is 45 bundles. With 10–15% waste, plan on about 50 to 52 bundles, plus starter and ridge cap shingles. If 1,500 sq ft is your house size rather than roof size, you’ll likely need 55 to 65 bundles.
What color roof increases home value?
There’s no single color that guarantees a higher sale price, but neutral shades like charcoal, gray, black, and weathered wood tend to have the widest buyer appeal because they match most siding and brick. The best color is one that complements your home’s exterior and fits the neighborhood. In wet climates like ours, algae-resistant shingles help any color stay looking clean longer.
How long does a 30-year shingle roof really last?
In real-world conditions, a “30-year” shingle roof usually lasts about 20 to 25 years. The “30-year” label is a warranty term, not a promise of lifespan. Ventilation, installation quality, and climate matter a lot. In the Pacific Northwest, moss growth and constant moisture can shorten shingle life if the roof isn’t maintained, which is why regular moss removal and gutter cleaning pay off.
Hidden Costs That Change Your Price Per Square
Even with a solid estimate, these can push the final number up:
- Soft or rotted decking found during tear-off. This is common on roofs that were poorly installed or leaked for years.
- Multiple old layers of shingles to remove.
- Steep pitch (generally 8/12 and above), which needs extra safety gear and slows the crew.
- Complex roof shapes with many valleys, dormers, or skylights.
- Chimney flashing that has to be rebuilt rather than resealed.
- Ventilation upgrades to meet code or manufacturer warranty requirements.
If you’re not sure whether your roof needs a full replacement at all, read our guide on roof repair vs. roof replacement, or check our list of the most common roof leak sources we find on Sandy homes.
How to Save Money Without Cutting Corners
- Get at least three line-item quotes and compare them by square, using the same method (measured or ordered).
- Ask whether decking is priced as an allowance, and request photos of any damaged boards they replace.
- Choose mid-range architectural shingles over designer lines if budget is tight. You get most of the durability for much less.
- Schedule in the off-peak season when crews have more availability.
- Check if your roof qualifies for an insurance claim if the damage came from a storm or a fallen tree.
- Don’t skip the important details like ice and water shield in valleys or proper ventilation. These protect your investment far more than a premium color does.
Get an Accurate Price for Your Roof in Sandy, Oregon
Online numbers give you a starting point, but your actual price per square depends on your roof’s pitch, layers, decking condition, and design. At Red Stag Roofing, we’ve spent over 30 years roofing homes across Sandy, Gresham, Estacada, Clackamas, and parts of Portland. We measure your roof, show you the actual number of squares, and give you a clear, itemized estimate with no surprises.
Call us at (503) 926-1835 or request your free estimate today.