When addressing low slope roofing, homeowners often face the challenge of making the right choice to protect against water damage. Many opt for architectural shingles as a cost-effective solution for their porch roofs. However, architectural shingles may not be the most effective option for low slopes, particularly concerning water resistance. This leads to having to replace this section with a rolled roofing porch repair.

In this article, we will explore the advantages of using rolled roofing, specifically modified bitumen, and share Birds Eye Roofing’s firsthand experience in rectifying a leaky back porch with the exceptional water-sealing properties of rolled roofing.

Low Slope Porch Repair

What is a low slope?

Any slope that is below 4/12 (roof rises 4 or less inches over a 12 inch run) is considered low slope. When roofing low slope areas, special considerations are necessary.

  • Architectural shingle can be used to 4/12 slope
  • 3-tab shingles can be used to 2-12
  • Rolled roofing can be used to 0.25/12
  • TPO or flat roof products need to be used for 0/12 slopes

Below is an example of how a low slope in improperly installed with architectural shingles on a slope that is below 4/12 units. The bricks are in the photo as they were holding a tarp over the area to slow the leaks until it could be repaired. There were previous repairs that did not work as well.

Improperly installed architectural shingles on a low slope

The Challenge of Low Slope Roofing

Low slope roofs present unique drainage challenges. Unlike steeper roofs that efficiently shed water, low slopes can lead to water accumulation, raising the risk of leaks. Traditional architectural shingles, designed for steeper pitches, often struggle to provide the necessary water-sealing protection on low slopes.

Why Rolled Roofing is a Better Choice

Modified bitumen, or rolled roofing, stands out as an excellent solution for low slope roofing due to its exceptional water-resistant properties. Here’s why:

  1. Superior Waterproofing: Modified bitumen is purpose-built to deliver outstanding waterproofing capabilities. Its multi-layered construction creates a seamless and watertight barrier that effectively repels water, preventing leaks even on low slopes.
  2. Durability: Rolled roofing demonstrates remarkable resilience to the elements, including heavy rain, intense sunlight, and extreme temperatures. It doesn’t crack or warp, ensuring long-term reliability. Rolled roofing on a back porch is a much better option to have under the shingles than ice and water due to its superior water protection on low slope roofs and a lifespan of 20 years.
  3. Low Maintenance: Unlike traditional shingles, which can demand more frequent maintenance, modified bitumen requires minimal upkeep. This is particularly significant for low slope roofs, given the challenges of accessing them for repairs.

The Birds Eye Roofing Experience:

Birds Eye Roofing confronted a challenging situation when a client’s back porch, roofed with architectural shingles on a low slope, began to leak. Despite utilizing tarps, water persisted in infiltrating the structure due to the roof’s inadequate pitch for traditional shingles.

Recognizing the need for a more effective solution, Birds Eye Roofing decided to install modified bitumen rolled roofing on the porch. The results were remarkable. The installation established a resilient, waterproof seal that conclusively resolved the leak issues.

By selecting rolled roofing for this low slope roof, Birds Eye Roofing not only repaired the existing problem but also provided their client with a long-lasting, low-maintenance roofing solution that would protect the porch for years to come.


Low slope roofing, particularly on porch roofs, necessitates specific attention to prevent water infiltration. Architectural shingles, while appropriate for steeper pitches, may not offer the requisite water-sealing protection for low slopes. Rolled roofing, specifically modified bitumen, delivers a superior solution for low slope roofing due to its exceptional waterproofing capabilities, durability, and low maintenance requirements.

Birds Eye Roofing’s firsthand experience with rolled roofing porch repair highlight the effectiveness of this choice in rectifying leak issues and providing enduring protection for low slope roofs. When contemplating roofing options for your low slope structures, rolled roofing should be at the forefront of your considerations for reliable, water-sealed protection.