Top 5 Roofing Issues Caused by Irish Weather (And How to Prevent Them)

If you live in Ireland, you know the weather can be relentless. Between driving rain, gale-force winds, and freeze-thaw cycles, your roof takes a battering year-round. After 15 years and 500+ projects across Dublin and Leinster, these are the five most common roofing issues we encounter, along with our advice on preventing them before they become costly emergencies.

1. Wind-Lifted and Missing Slates or Tiles

Ireland's prevailing south-westerly winds regularly gust above 100 km/h during winter storms. Over time, even properly secured slates and tiles can work loose as the mortar on ridge tiles deteriorates and nail fixings corrode. A single missing slate might not seem urgent, but it exposes your felt and timbers to water ingress, which can escalate rapidly.

Prevention: Have a professional roofer inspect your roof annually, ideally in autumn before storm season. Re-bed any loose ridge tiles and replace corroded fixings. If your roof is over 30 years old, consider a mechanical dry ridge system, which is far more wind-resistant than traditional mortar bedding.

2. Blocked Gutters and Downpipes

Ireland's lush greenery means leaves, moss, and debris accumulate in gutters quickly, especially if you have overhanging trees. Blocked gutters cause water to overflow and run down walls, leading to damp, staining, and even structural damage over time. In freezing conditions, blocked gutters can form ice dams that add enormous weight to your fascia boards.

Prevention: Clean your gutters at least twice a year (spring and autumn). Install gutter guards or leaf filters if trees are nearby. Check that all downpipes are flowing freely by running a hose through them.

3. Moss and Algae Growth

Ireland's damp, mild climate is perfect for moss and algae growth on roof tiles. While a little moss might look quaint, heavy moss growth retains moisture against your tiles, accelerates their deterioration, and can lift tile edges, creating pathways for water to enter. On flat roofs, algae can degrade membrane surfaces over time.

Prevention: Have moss professionally removed (never pressure wash roof tiles, as this damages the surface). Apply a biocide treatment to inhibit regrowth. Trim overhanging branches to increase sunlight and airflow across the roof surface.

4. Lead Flashing Failures

Lead flashing seals the junctions between your roof and features like chimneys, walls, and dormer windows. Over decades, lead fatigues from thermal expansion and contraction, develops cracks, and can pull away from mortar joints. Failed flashing is one of the most common causes of persistent roof leaks in Irish homes, and one of the hardest for homeowners to diagnose themselves.

Prevention: Include flashing in your annual roof inspection. Look for signs of cracking, lifting, or discolouration from inside your attic. When flashing needs replacement, ensure your roofer uses code-compliant lead (minimum Code 4) and stepped flashing techniques rather than simple cover flashings.

5. Flat Roof Ponding and Blistering

Flat roofs are increasingly common on Irish extensions and commercial buildings, but they're vulnerable to ponding (standing water that doesn't drain within 48 hours) and blistering (bubbles in the membrane caused by trapped moisture). Ireland's high rainfall makes proper drainage critical, and even small installation defects can lead to premature failure.

Prevention: Ensure your flat roof has a minimum fall of 1:40 (ideally 1:60) to outlets. Have it inspected annually for signs of ponding, tears, or blistering. Choose a high-quality single-ply membrane (EPDM or TPO) with a minimum 20-year warranty, installed by an accredited contractor.

When to Call a Professional

If you notice any of the following, it's time to get your roof assessed by a qualified roofing contractor:

• Damp patches or water stains on ceilings or walls
• Visible daylight through the roof from inside the attic
• Missing, cracked, or slipping slates/tiles
• Sagging or bowed sections of the roofline
• Increased energy bills (indicating lost insulation)

We offer free roof surveys across Dublin and Leinster. We'll check your roof, flag any problems, and give you straight advice on whether you need a repair or a replacement, along with a clear, itemised quote.