Tips for Removing Mold and Algae from Roof in Billings

by | May 13, 2025 | Billings, Blog

If you’re a homeowner, chances are you’ve glanced up at your roof and noticed dark streaks or greenish patches that weren’t there before. Maybe you’ve even thought, “That can’t be good…” and you’re right to be concerned. Algae, mold, and mildew are more than just an eyesore — left untreated, they can actually damage your roof and shorten its lifespan.

In Billings, we see our fair share of this kind of thing. The changing seasons and storm cycles create the perfect conditions for moisture buildup, which can lead to growth on shingles, particularly on the north-facing slopes of your home where the sun doesn’t hit as hard.

So, what’s the best approach for algae removal and mold on a roof in Billings MT? How do you clean roof stains without damaging your shingles or voiding your warranty?

We’re glad you asked. At Kirkness Roofing, Inc., we’re here to walk you through it — step-by-step — so you can make the best decisions for your home and your wallet.

Why Mold and Algae on Your Roof Are a Bigger Deal Than You Think

It’s More Than Just a Cosmetic Issue

We often hear, “It’s just a stain, right?” Not exactly. The dark streaks you’re seeing are usually caused by a bacteria called Gloeocapsa magma. Over time, this bacteria feeds on the limestone filler in your shingles, weakening them and reducing their effectiveness.

Mold Can Impact Indoor Air Quality

Mold spores from your roof can travel through attic vents and HVAC systems, potentially affecting the air inside your home. If you or someone in your household has allergies or asthma, this is not something to overlook.

Your Roof’s Lifespan is at Risk

Shingle roofs already have enough to battle — wind, hail, and UV exposure. Throw in algae and mold, and you’re accelerating wear and tear. That’s why roof mold treatment isn’t just a nice-to-have. It’s part of protecting one of your biggest investments.

How to Remove Algae from Roof Surfaces Without Causing Damage

Cleaning your roof isn’t as simple as grabbing a pressure washer and going to town. In fact, that’s the last thing you should do.

The Dangers of DIY Pressure Washing

High-pressure water can strip the granules off your shingles — the very layer that protects them from UV rays and gives them their color and texture. Once those granules are gone, your roof is vulnerable to sun damage and premature aging.

Use the Right Cleaning Solution

When it comes to cleaning roof stains in Billings, a low-pressure chemical wash is the preferred method. The right mix usually includes water, bleach (sodium hypochlorite), and a surfactant to help the solution stick to the roof and penetrate the growth.

Think of it like washing your car — you want enough cleaning power to remove the grime, but not so much that you ruin the paint.

Soft Wash Method: A Safer, Smarter Approach

The soft wash technique uses a gentle stream and specialized solution to kill algae and mold at the root. It doesn’t just rinse the surface — it targets the source. This is the approach we recommend for any roof mold treatment, and it’s what we use when cleaning our customers’ roofs professionally.

How to Know When It’s Time to Call a Professional

When the Stains Keep Coming Back

If you’ve tried to clean your roof before and the stains returned within a few months, it’s time to get to the root of the issue. You may be dealing with moisture retention, poor ventilation, or even defective materials.

If You’re Not Comfortable Working on a Roof

Let’s be real: not everyone has the tools or training to work safely on a roof. Slippery slopes, chemical solutions, and the wrong shoes are a recipe for injury. That’s why it’s often safer — and more cost-effective — to call in the pros.

If You Want to Preserve Your Warranty

Many shingle manufacturers void warranties if improper cleaning methods are used. At Kirkness Roofing, we follow manufacturer guidelines to make sure your roof stays protected in every sense of the word.

Preventing Future Growth on Your Roof

The best kind of roof algae removal is the kind you don’t have to repeat every year.

Install Zinc or Copper Strips

These metals release particles when it rains that naturally inhibit algae and mold growth. It’s a small addition with a big payoff — and something we can include as part of a routine maintenance service.

Improve Ventilation and Drainage

A dry roof is a healthy roof. If you’re seeing recurring mold or algae, it might be a sign that your attic isn’t ventilating properly or your gutters aren’t channeling water away effectively.

We can inspect both during your roof estimate and make recommendations to help your entire system work better together.

How Kirkness Roofing Can Help with Roof Mold Treatment

We’re not just another roofing company offering one-size-fits-all solutions. With more than 40 years in the business and over 80 years of combined team experience, Kirkness Roofing knows what works in our local climate — and what doesn’t.

Here’s what we bring to the table when it comes to roof algae removal and cleaning roof stains in Billings:

Safe and Effective Soft Washing
We use non-abrasive methods to protect your shingles and kill algae and mold deep down.

Warranty-Friendly Techniques
As a GAF Master Elite and Owens Corning Preferred Contractor, we know how to work within warranty guidelines — and protect your investment.

Thorough Inspection and Honest Advice
Sometimes stains are just stains. Other times, they’re the first sign of a bigger problem. We’ll help you tell the difference.

Long-Term Solutions
From ventilation upgrades to copper strip installation, we’re thinking beyond today’s cleaning — we’re helping you keep it from coming back tomorrow.

Take the Next Step Toward a Cleaner, Healthier Roof

If you’ve noticed dark streaks, mossy patches, or lingering roof stains, don’t wait until they become a bigger issue. A simple cleaning today can save you thousands in roof repairs down the line — not to mention restore your curb appeal.

Call Kirkness Roofing, Inc. today at 406-256-1798 or email us at Info@kirknessroofing.com to schedule your estimate. We’ll take a close look, offer honest feedback, and if needed, safely handle the cleaning and roof mold treatment with professional care.

Because your home deserves a roof that’s not just built to last — but looks good doing it.

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