Low-Slope & Detail Solutions Built for the Pacific Northwest.
Continuous membrane systems protect the additions, porches, and flat sections of your home that shingles can't — engineered to shed standing water and tie cleanly into your pitched roof.
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Seamless Protection
Continuous membrane systems that shed standing water and protect low-slope areas of your home.
Built for Water
Engineered to handle the slow drainage and ponding water that low-slope roofs face in Puget Sound.
Detail Expertise
Specialized flashing and transition detailing that tie low-slope areas into the rest of your roof.
Complete Roofing System
Installed as part of a full system with proper underlayment, flashing, and drainage planning.
Why Homeowners Choose Low-Slope Membrane
Shingles simply aren't designed for low-pitch areas. A continuous membrane system is the correct, code-compliant way to protect the flat and low-slope sections of your home — and it ties seamlessly into the rest of your roof.
- Continuous, watertight membrane that handles slow drainage and ponding water
- Heat-welded or self-adhered seams for a monolithic, leak-resistant barrier
- Ideal for additions, porches, carports, and flat roof sections
- Ties cleanly into pitched roofing with proper transition flashing
- Resists moss, UV, and Pacific Northwest freeze-thaw cycles
- Lightweight and low-maintenance compared to built-up gravel systems
Common Low-Slope Applications
These are the areas of your home where shingles fail and a membrane system makes all the difference.
Home Additions
Low-slope roofs on additions and bump-outs need a true membrane system to stay watertight where shingles alone would fail.
Porches & Overhangs
Flat or low-pitch porches and entry overhangs are common leak sources — a membrane protects them for the long haul.
Dormers & Valleys
Complex dormer walls and dead valleys collect water and debris. Membrane detailing keeps these trouble spots sealed.
Membrane vs. Shingles on Low-Slope Areas
A clear comparison so you can see why membrane is the right choice for low-pitch sections.
| Feature | Membrane System | Asphalt Shingles |
|---|---|---|
| Minimum Pitch | Down to 1/4:12 (nearly flat) | Requires 2:12 or steeper |
| Water Handling | Sheds standing and ponding water | Can back up under slow drainage |
| Seam Type | Heat-welded or self-adhered — monolithic | Overlapped courses — not watertight at low pitch |
| Lifespan | 20 to 30+ years with proper maintenance | Prone to premature failure on low-slope areas |
| Best Use | Additions, porches, flat sections, dead valleys | Pitched roofs 2:12 and steeper |
| Maintenance | Low — periodic inspection and seam checks | High on low-slope — frequent leak repairs |
Our Low-Slope Installation Process
A clear, transparent process from estimate to final walkthrough.
Inspection & Estimate
We assess the slope, drainage, and existing conditions of your low-slope area, then provide a free, itemized estimate.
Tear-Off & Deck Prep
We remove the old roofing down to the deck, inspect every sheet, and replace any rotted or saturated wood.
Membrane & Flashing
We install a self-adhered or heat-welded membrane with metal drip edge and transition flashing tied into the pitched roof.
Seams & Details
Seams, penetrations, and corners are detailed and sealed to create a continuous, monolithic barrier.
Cleanup & Walkthrough
We clear all debris, check drainage flow, and walk the job with you to confirm everything meets our standard.
Installation Details That Matter
Low-slope roofs are unforgiving. We focus on the details that keep them watertight for the long haul.
Self-Adhered Membrane
A peel-and-stick base sheet bonds directly to the deck for a reliable, watertight foundation.
Transition Flashing
Metal flashing ties the low-slope membrane into the pitched roof so water flows cleanly across the transition.
Penetration Sealing
Vents, pipes, and skylight curbs are sealed with membrane flashing to stop leaks at every penetration.
Drip Edge & Drainage
Metal drip edge and proper slope direct water off the roof and away from your home's structure.
Seam Detailing
Overlaps and seams are rolled and sealed so the membrane acts as one continuous sheet.
What's Included in Your Low-Slope Project
Every low-slope membrane project includes:
Trusted by Homeowners Across Puget Sound.
Read real, unfiltered reviews submitted directly on our official Google Business Profile.
"PAC Roofing LLC did a fantastic job installing our new metal roof. We are thrilled with the look and function of the roof. It's gorgeous! We had solicited multiple bids for the job and PAC Roofing LLC was the most reasonable."
"Thank you for trusting PAC Roofing LLC with your project!"
"Doug came over and gave me the best price on replacing my roof on my house and out building. He also included gutters all the way around both of them too. His crew did an excellent job and I would highly recommend his business to anyone."
"Thank you for your business, Jay!"
"Doug was recommended by a neighbor and honestly, we were super impressed with Doug, his team, and the quality work they did! He responded quickly to all my questions promptly and his team did a great job from start to finish."
"Thank you for the recommendation!"
“They replaced our roof in a single day, kept the yard spotless, and walked us through every option before any work started. We finally feel good about how our home will hold up through a Puget Sound winter.”
Frequently Asked Questions
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Free, no obligation estimate from a local team you can trust.