💧 Common Causes of Roof Window Leaks

A leaking roof window doesn’t always mean the window itself is faulty.

Here are the most common causes we see at Certified Installers:

1️⃣ Incorrect Flashing Installation

Using the wrong flashing kit — or fitting it incorrectly — is the number one cause of leaks.

2️⃣ Blocked Drainage Channels

Debris can prevent water from draining correctly around the frame.

3️⃣ Damaged or Slipped Roof Tiles

Sometimes the issue lies with the surrounding roof, not the window.

4️⃣ Failed Glazing Seals

Water can enter internally if seals have deteriorated.

5️⃣ General Ageing

Like any external product, materials naturally wear over time.

⚠ Why You Shouldn’t Ignore It

Water ingress can lead to:

• Internal plaster damage

• Timber rot

• Mould growth

  
  

Professional diagnosis is essential before assuming full replacement is required.

We may be able to repair your skylight and if not a replacement would be required. We are happy to advise the best option depending on your individual circumstance.

Contact us for professional advice.