Composition shingles are the same thing as asphalt shingles, and they’re a practical choice for many Portland homes. They offer a wide range of styles and generally cost less upfront than materials like metal. In our wet climate, the right shingle matters, but so do moss control, ventilation, and quality installation.
Here’s what you should know before you choose a new roof.
What are composition shingles?
Composition shingles get their name from the mix of materials inside them: asphalt, fillers, a fiberglass reinforcement mat, and protective granules. “Composition” is an older term, so you may see “asphalt shingles” on a quote for the same product.
Don’t confuse them with composite shingles. Composite usually refers to synthetic shingles made from polymers, which are a different product with different pricing and performance.
The three main types
Most roofs use one of three shingle grades. The right one depends on your budget, how long you plan to stay, and the look you want.
| Type | What it is | What it means for you |
|---|---|---|
| 3-tab | A single flat layer cut to look like three shingles | Usually the lowest-tier option, with a simple, uniform look |
| Architectural | Two or more laminated layers, also called dimensional | Thicker and more textured, and the most popular choice in North America |
| Premium | The thickest laminated shingles, also called luxury | Often designed to resemble slate or cedar shake, usually at the highest price |
For many homeowners, architectural shingles offer a good balance of cost, appearance, and durability. A premium shingle may make sense if you want a specific look or plan to stay in your home for a long time.
How long do composition shingles last?
Inspection association InterNACHI’s general chart lists about 20 years for 3-tab and 30 years for architectural shingles. Treat those as rough estimates rather than promises, since weather, design, material quality, and maintenance all affect a roof’s life.
A warranty term isn’t a lifespan either. A “lifetime” warranty has specific terms and limits, so read what it covers before comparing products. For a closer look at other materials, see our guide to how long different roofs last.
What Portland’s climate means for your shingles
Portland gets about 37 inches of precipitation a year, and most of it falls during the cooler months. Those long damp stretches create a few challenges for a shingle roof.
- Moss: Oregon State University Extension says moss on asphalt roofs can lift shingles and let water reach the layers below. Trimming nearby trees to let in more sun is its most effective long-term advice.
- Algae: Algae-resistant shingles use special granules to help prevent black streaks. They’re worth asking about, especially on a shaded roof.
- Moisture below the shingles: A wet climate makes the layers you can’t see important too. That includes roof underlayment, flashing, and ventilation.
- Wind: Shingles rely on sun-activated sealant to bond properly, and cool weather can slow that process. Ask how your roofer handles installation in cold weather.
If you see moss, be careful about how it’s removed. OSU Extension warns that improper pressure washing can damage shingles, so hire a professional or use a long-handled scrub brush from a safe position.
Are composition shingles the right choice?
They’re often a good fit if you want a proven roof at a lower upfront cost, or if you may sell your home before a longer-lasting roof would pay off. Metal may be worth a look if you plan to stay for decades and can spend more upfront.
Our metal vs. asphalt comparison can help you weigh the tradeoffs for your home.
What affects the cost?
Your price depends on more than the shingles themselves. Roof size, slope, layout, tear-off needs, damaged decking, ventilation, and flashing can all change the total. That’s why comparing quotes by the total alone can be misleading.
When you compare quotes, check that each one lists:
- The shingle brand and product line
- Whether the old roof will be fully removed
- The underlayment, flashing, and ventilation included
- How damaged decking will be priced if the crew finds it
- The manufacturer and workmanship warranty terms
Our roof replacement cost guide explains more of what goes into a price.
Thinking about a new composition roof?
Peak Performance Roofing is a family-owned company based in Wilsonville, with crews who average 14 years of experience. We install composition roofs for homes across the Portland metro area and SW Washington.
Call 971-979-7325 or request a free quote to talk through your options. If you’d like to spread out the cost, you can also review our financing options.
Composition shingle FAQs
Are composition and asphalt shingles the same?
Yes. Composition is an older name for asphalt shingles. You may see either term on a quote, so ask for the product name if you’re not sure.
What’s better, 3-tab or architectural shingles?
Architectural shingles are generally thicker, heavier, and longer-lasting, with better warranties. They usually cost more than 3-tab shingles, but many homeowners prefer their look and durability.
Can you put new shingles over old ones?
Sometimes, but a full tear-off lets the crew see and repair the decking underneath. Some manufacturer warranties also require it, so ask how each option would affect your coverage.
Do composition shingles need maintenance?
Yes. Keep them clear of debris, watch for moss, and keep gutters flowing. Stay off the roof when it’s wet, and hire a professional for anything you can’t do safely.
