Brown Stains on Siding in Winter? Here’s What’s Causing Them (And How to Fix It)

If you’ve ever looked at your home in the winter and noticed brown or dirty streaks running down your siding, you’re not alone.

Take a look at the image above.

Those vertical stains aren’t mold.

They aren’t rust.

And they’re not permanent damage.

They’re caused by ice dams and dirty roof runoff.

What’s Actually Happening?

During the winter in the Northeast, snow builds up on your roof. When heat escapes from your attic, it melts the snow. That water runs down your roof… and then refreezes at the colder eaves.

This forms what’s called an ice dam.

As more snow melts, water backs up behind that ice. Instead of draining properly, it spills over the edge of the roof.

And here’s the part most homeowners don’t realize:

That water is dirty.

It carries:

• Asphalt shingle granules

• Roof dirt and debris

• Organic buildup

• Airborne pollutants

• Gutter sediment

When it runs down your siding and freezes repeatedly, it leaves behind those brown vertical streaks you see in the photo.

Is It Damaging?

At first, it’s cosmetic.

But if left untreated:

• The staining can set in

• Organic buildup can begin growing in warmer months

• It can prematurely age painted or vinyl siding

• It lowers curb appeal (especially if you’re thinking about selling)

And let’s be honest — it just makes your house look neglected.

The Good News: It’s Completely Cleanable

At Blueline Exterior Cleaning, we use a professional soft washing process designed specifically for:

• Winter roof runoff staining

• Ice dam streaking

• Organic buildup

• Oxidation-safe siding cleaning

We don’t blast your siding with high pressure.

We use the right detergents, proper dwell time, and controlled rinsing to safely restore your home’s exterior without damage.

Why You Shouldn’t Just Pressure Wash It Yourself

High pressure:

• Can force water behind siding

• Can damage paint and vinyl

• Won’t properly treat the root cause of staining

This isn’t just dirt — it’s bonded roof runoff residue.

It requires the right chemistry and technique.

Serving Homeowners Throughout the Northeast

Winter is tough on homes. Ice dams are common. And these streaks show up on houses every year.

If your siding looks like the photo above, it’s not ruined.

It just needs the right cleaning.

Get Your Home Looking Clean Again

If you’re dealing with winter staining or ice dam runoff marks, contact Blueline Exterior Cleaning for a professional assessment.

We’ll restore your siding safely and effectively.

📞 Call today

💬 Or request a quote online

Your home should look as strong and clean as it stands.