Can a roof leak cause damp?

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Damp can enter our homes in a variety of different ways. One of the most common is penetrating damp. The reason this is more common than other types of damp, such as rising damp, is it can enter anywhere there is a defect in your property.

One very common way for water to penetrate a property is via a leak in the roof. This is usually quite easy to identify, as you will usually see damp patches on walls and ceilings in your upstairs rooms.

If you have access to an attic, you will usually be able to follow the water, and find exactly where it is entering. Obviously if you don’t have safe access, you should simply ring a professional who can diagnose the problem.

Damp is quite common due to roof leaks, especially during the wet winter months. Often a leak will start small, then over time it can progress into a bigger problem. This can result in much more internal damage caused by damp and mold.

As soon as you notice any kind of roof leak, you should call a professional roofer. If you do leave it, the damage can potentially get worse and the cost to fix it is likely to rise.

can a roof leak cause damp

Common causes of damp due to a roof leak

There are several reasons water could be leaking in via your roof, these include:

  • Slipped or damaged tiles – Poorly fitted, cracked, and slightly slipped tiles will usually result in small consistent leaks. Whereas a missing tile is likely to let a lot more water in.
  • Issues with the felt on your roof – This is slightly less common, as the felt is a last line of defense when water gets past the tiles. When this happens, water should run down the felt into your gutters. However, if there is any damage or deterioration this can allow water to enter. Again, this is likely to be a slow leak and could go unnoticed, leading to a higher risk of damp.
  • Damaged flashing – Flashing can be found around chimneys, in roof valleys, as well as around dormer and Velux windows. If this is fitted poorly or becomes damaged it is very likely to let moisture in.
  • Broken pointing – Just like anywhere else in your property, pointing is a common cause of penetrating damp. All you need is a small bit of damage and water can easily enter. This could be due to wear and tear, weather damage, or bad quality pointing.

    It is also quite common in winter, for pointing to take on water which freezes. As it freezes the water expands and blows the pointing out
  • Problems with guttering and down pipes – This is also quite common and can happen because of damage and blockages. If you have already noticed damp and you have leaking or dripping guttering, then it is very probable that this is the cause.

If your roof is in reasonably good shape, then most of the above can be repaired. However, more serious issues, especially those in older roofs could mean you need an entirely new roof installing.

Can a roof leak cause mold?

The quick answer to this is yes, a roof leak can cause mold. Any type of damp that enters your home has the potential to cause mold.

If you leave a damp problem for even a short amount of time, then mold is almost inevitable. Mold spores are present in most areas inside and out. When these spores are met with the right conditions, it is very easy for mold to form and quickly spread.

Mild condensation is often enough to trigger mold, so a leak coming from your roof is highly likely to result in it forming. This will continue to get worse if you don’t stop the leaks and fully dry the damp area.

Mold likes a wide variety of materials. It particularly likes woods and paper products including wallpaper and even plasterboard. This is because these products contain cellulose, which the mold feeds on. This means there are many building materials in your home, that will allow mold to thrive if given the chance.

Mold and damp are quite destructive, and they can both cause big problems. Not only can they destroy decorative features in your house, but they can also cause certain structural issues. This could be anything from a ceiling falling in, to more serious damage in areas such as structural timber.

Its also worth noting, that damp timber can attract other potential problems, such as rot, and wood burrowing insects like woodworm.

How to stop damp from a roof leak

To get rid of damp you need to fix the root cause of the problem. In most cases this will require the help of a qualified roofing contractor. Only once the issue is fixed, will you be able to carry out internal repairs.

Attempting to repair roof issues on your own, could result in making the problem worse. Not only that, accessing your roof is dangerous and the risk of injury is high. This is especially true if you don’t have all the proper access and safety equipment.

One thing you can do whilst you wait for a professional, is try to divert the flow of water. If there is an obvious leak, you could use something simple like a bucket to capture it. This would stop more water entering your home and making damp problems worse.

How to save money on your roof repairs

Having a roof repaired can be expensive. However, the sooner it is done, the cheaper it is likely to be. If the whole roof needs replacing, then the cost can be quite considerable. However, you can save money by getting multiple quotes.

Obviously, if your leak is causing problems right now, then waiting for quotes might not be the best idea. Waiting around can delay the work and allow the problem to get worse. Therefore, it is much better to use online trade comparison sites.

There are several advantages to getting quotes online. These include:

  • You can get multiple quotes online almost instantly.
  • Local companies that use these sites know they are competing for the work. This means prices tend to be much cheaper (we have seen savings as high as 50%)
  • Most companies won’t charge a call out fee.
  • Plus, all the companies are rated and reviewed on the comparison site.

As a result, you end up getting the best local companies at the absolute best price.

To see our favourite roofing comparison site and get local online quotes Click Here