What Happens to Your Home When You Leave It Dirty Over the Winter?

When the cold weather hits Massachusetts, pressure washing season ends — but the damage from organic growth doesn’t. Leaving algae, mildew, mold, or moss on your siding, roof, deck, or concrete throughout the winter can lead to serious and expensive issues once spring arrives.

Even though it’s too cold to soft wash now, it’s important to understand what happens when your home enters winter dirty, and why cleaning before freezing temperatures is the best way to protect your property.

1. Moisture Gets Trapped, Freezes, and Expands

Organic growth acts like a sponge. Algae, mildew, and moss hold moisture against the surfaces of your home. During winter’s freeze–thaw cycles, that moisture repeatedly expands and contracts.

This puts stress on:

• Vinyl siding
• Wood trim
• Fascia boards
• Paint
• Deck boards
• Concrete
• Brick and mortar

The result? Cracking, warping, peeling paint, and premature material wear.

2. Organic Growth Continues Spreading Under Snow and Ice

A lot of people assume algae and mildew “stop growing” in the winter. Unfortunately, that’s not true. They slow down, but they do not stop — especially when insulated by snow and continual moisture.

By spring, homeowners often discover:

• Heavier staining
• Expanded algae streaks
• Moss that has rooted deeper
• New areas of discoloration

3. Stains Become Harder (Sometimes Impossible) to Fully Remove

When organic matter sits on siding or shingles for months, winter UV exposure can bake stains deeper into the material. What would have been a simple fall soft wash sometimes becomes a deeper, more aggressive cleaning in the spring — and in some cases, the discoloration becomes permanent.

4. Mold and Mildew Can Begin Affecting Indoor Air Quality

Heavy exterior buildup around windows, gaps, or older siding can eventually make its way indoors. Winter moisture amplifies this process, especially during long periods of freezing and thawing.

5. Decks, Fences, and Concrete Take Additional Damage

Organic matter weakens exterior surfaces:

• Wood can soften, leading to warping, cupping, or splitting.
• Concrete can scale, crack, or pit as algae holds moisture against its surface and freezes.

By the time snow melts, these surfaces often show noticeable deterioration.

The Best Time to Clean Your Home

Although soft washing isn’t possible during freezing temperatures, the goal is to help homeowners plan ahead. In Massachusetts, the ideal exterior cleaning window is April through early November.

A spring, summer or fall soft wash removes organic growth at the root, protects your surfaces, and prevents the freeze–thaw damage that can develop when your home goes into winter dirty.

Plan Ahead for Next Season

If you want to protect your siding, roof, deck, and concrete from winter damage, schedule your cleaning before next season’s cold weather arrives. Planning ahead ensures your home is fully protected and helps you avoid the spring rush when demand is high. Give Code 3 Power Washing a call now! 508-784-1220