Don't forget the roof! Reasons why roof maintenance matters

10 Jan 2024 The Lodge Real Estate Team


Whether you intend to sell your house or live in it for the next twenty years, knowing how to maintain a roof is vital to keeping your home safe, and its value growing.

With the leaky home fiasco still having ongoing ramifications for many New Zealanders, here are a few common roofing issues that have the potential to turn into real problems and reduce your property’s value.

Overflowing gutters

Full gutters not only cause water to overflow and pool in undesirable spots; they make your roof susceptible to mould and mildew—which can get into/under your roof (and exterior walls).

How to fix it

Gutter cleaning is relatively easy to do yourself if you are fit and physically able. Grab a step ladder and some gardening gloves and you’re set. If your house is more than one story, consider hiring scaffolding, or getting a professional to do it for you.


There are a number of things can cause roof discolouring, from trees dropping leaves and branches, to rusting nail and screw fasteners.

Mould, mildew and lichen can appear as green, grey, brown or black and is usually caused by a buildup of organic matter—such as soil, plant debris and animal matter.

How to fix it

Mould, mildew and lichen can be washed away with a roof cleaning product. You can get these from most hardware stores.

Red discolouring is often rust, and it is a common problem for metal roofs, especially if the wrong fasteners have been used.

How to fix it

To treat a rusting roof, remove all the rusting nails or screws and scrub the affected area(s) with sandpaper and a wire brush. Repair or replace the metal sheets and recoat them with metal primer and roofing paint. Here’s a step-by-step guide.

If your roof is turning white, it could be a sign of salt buildup—which you can wash away—or that your tiles are absorbing water and are near the end of their life.

How to fix it

If your tiles are absorbing water, it could mean you’ll need to replace your roof. Consult a roof inspector before taking any action.

Cracked tiles

Cracked tiles are usually caused by extreme weather—such as high wind or hail. However, they can also crack if walked upon. It’s not a good idea to leave broken tiles for long, as they can cause further damage, which can lead to issues with weathertightness.

How to fix it

Cracked tiles are relatively easy to fix. Small cracks can be filled with plastic roofing cement, while large cracks and broken tiles will need to be replaced. You’ll also need to have the right equipment, namely a proper roofing ladder, to avoid causing further damage. For any major damage, we recommend calling a roofing professional.


Leaks have the potential to cause dangerous and costly damage if left untreated. The earlier you can treat a leak, the better. Tell-tale signs include dripping, spots on your exterior walls, water stains, mould and mildew on your ceiling and walls.

Here are a few things to check to treat and prevent leaks

  • The membrane underneath any cracked tiles: damage to this waterproof membrane is one of the most common causes behind a leaky tile roof. To fix, use a bonding adhesive to apply a fresh piece of membrane over the damaged area.
  • Roof flashings: check the material around your skylights, vents and pipes. Small holes can be repaired with a patch of the same type of roof flashing material and roof cement, but if there is significant damage, you’ll need to replace all of it.
  • Look for environmental damage: where plants and/or animals have wormed their way in. Depending on whether you have a flora or fauna problem will determine how to fix it. It could be a simple de-weed, or a matter of calling in a rodent or insect exterminator.

Read more: How to find a roof leak

How often should I clean my roof?

The answer depends on the material your roof is made out of, and where you live. Areas that are prone to high levels of rainfall or are exposed to the sea will need to be checked and cleaned more frequently.

As a guideline, roof maintenance specialists recommend washing your roof once a year, and any areas not exposed to rainfall every six months.

Stay safe

Keep safety in mind when working on your roof. Always have someone nearby in case of an emergency, never work on a roof when you are alone. If you are going to be walking across a steep pitched roof, wear a safety harness.

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