CalZone Logo
User
The Breathable Home

Ventilation & Condensation 2026

A roof that can't breathe is a roof that will fail. In 2026, as homes become more airtight to save energy, proper roof ventilation is more critical than ever to prevent timber rot and mould growth.

Cross-Flow Ventilation Systems

Ventilation Costs (2026)

Tile / Slate Vents (Installed)£85 – £145 / unit
Dry Ridge Vent System£250 – £450
Soffit Vents (Full House)£200 – £350
Felt Lap Vents (DIY Retrofit)£25 – £45 / pack

*Retrofitting ridge vents often requires scaffolding, which can add significantly to the total project cost.

The Ventilation Circuit

Think of your loft like a chimney. You need air coming in at the bottom and escaping at the top to carry moisture away.

1
Intake: Soffit or Over-Fascia vents.
2
Flow: Unobstructed space above insulation.
3
Exhaust: Ridge, Tile, or Gable vents.

Don't block the "Eaves Gap"

The most common cause of loft condensation is homeowners pushing their insulation right into the corners, blocking the gap where air enters from the soffits. Always use "Eaves Trays" or baffles to ensure a 50mm clear air path above your insulation.

Summer Cooling

Proper ventilation doesn't just stop damp; it also prevents your loft from becoming an oven in the summer.

Timber Longevity

Dry timbers can last for hundreds of years. Ventilation is the key to preventing rot.

Healthier Air

By preventing mould growth, you ensure the air in your home remains free from harmful spores.

Ventilation FAQ

Add Ventilation Now

Use our 2026 calculator to add professional ventilation components to your roofing project and protect your investment.