If your roof has turned green, grey, or black this season — you’re not alone.
Auckland’s cold, damp winters make it the ideal environment for moss, mould, and lichen to thrive on roofing surfaces, especially:
- Concrete tile roofs
- Decramastic (chip) metal roofs
- Older Colorsteel or iron roofs
- Shaded homes in leafy suburbs
The good news? There’s a safe, effective way to kill roof growth at the root — without damaging your tiles or metal.
It’s called biocide spray treatment, and it’s exactly what we offer at Metro Water Blasting.
👉 Learn more about our roof moss treatment service
Why Moss, Mould & Lichen Are Dangerous on Roofs
| Growth Type | Damage Caused |
|---|---|
| Moss | Soaks up water, keeping your roof constantly wet — causes tile cracking, iron corrosion |
| Mould | Stains surface and holds grime, reducing roof life |
| Lichen | Roots embed into coatings, lifting paint and breaking chip finishes (Decramastic) |
Left untreated, these organisms shorten your roof’s lifespan by years and lead to expensive leaks and repairs.
How Biocide Spray Treatment Works
Unlike high-pressure roof washing (which can damage delicate surfaces), our biocide-based treatment:
- ✅ Kills moss, mould & lichen at the root
- ✅ Uses a low-pressure application — no damage
- ✅ Reacts over time — growth dies off naturally with rain and sun
- ✅ Works on all roof types, including Colorsteel, tile, iron, and membrane
Treatment is best done in winter, while growth is active — so the biocide can penetrate deeply and work longer during the wet months.
👉 Book your roof spray treatment today
Suburbs in Auckland Where Roof Growth Is Worst
We treat roofs all across Auckland, but moss and lichen growth is especially common in:
- North Shore – Glenfield, Birkenhead, Albany, Torbay
- West Auckland – Titirangi, Te Atatū, Massey, Swanson
- South Auckland – Papakura, Māngere, Ōtāhuhu, Manurewa
- Central Auckland – Mount Eden, Sandringham, Epsom
- East Auckland – Pakuranga, Howick, Botany Downs, Flat Bush
Homes with trees, shade, and older roofs are at the highest risk.
Roof Types We Treat
✅ Concrete tile roofs
✅ Colorsteel and iron
✅ Decramastic (stone chip metal)
✅ Asphalt shingle and membrane roofs
✅ Older painted roofing
Whether your roof is brand new or decades old, we apply the right concentration and technique for long-term results.
Benefits of Roof Moss & Lichen Spray Treatment
- Prevents tile cracking and water entry
- Preserves your paint and roof coatings
- No need for dangerous high-pressure washing
- Results improve over time — lasting up to 18–24 months
- Cheaper than physical roof washing or re-coating
👉 Get a free quote for your Auckland roof
FAQs About Roof Moss Treatment
How long does it take to work?
➔ You’ll see visible results over 1–3 months as rain and sun break down the dead growth.
Will it damage paint or tiles?
➔ ✅ No — our application is low-pressure and safe for all roofing materials.
Is re-treatment needed every year?
➔ Not necessarily. Most homes only need treatment every 18–24 months if growth is moderate.
Do I need to be home?
➔ No — as long as we have access to your roof and water supply, we can carry out the treatment.
Book Your Roof Spray Treatment Today
If your roof has moss, lichen, or mould, don’t wait until it leaks or ruins your paint.
Our biocide spray solution is fast, effective, and lasts longer than traditional washing.
✅ Safe
✅ Affordable
✅ Ideal for winter
✅ Results that improve with time
👉 Click here to book your Auckland roof moss treatment
Serving all of Auckland — from Albany to Papakura, Henderson to Howick.