Types of Roof Drainage Systems

Last updated on June 17, 2023

Discover the various types of roof drainage systems in this comprehensive guide, designed to help you choose the perfect solution for your home or building.

Roof drainage systems are an essential part of any building’s construction. They protect the structure from water damage and ensure that rainwater is properly channeled away from the foundation.

But did you know that there are different types of roof drainage systems? Each system has its own unique features and benefits, making it important to choose the right one for your building’s needs. In this article, we’ll explore some of the most common types of roof drainage systems and help you determine which one is best suited for your property.

So whether you’re a homeowner or a commercial property owner, read on to learn more about how to keep your roof safe and dry with the right drainage system!

Conventional Gutters

types of roof drainage systems

Conventional Gutters are the most common type of roof drainage system. They consist of a trough that is attached to the edge of the roof, which collects rainwater and channels it away from your home or building through downspouts.

These gutters come in various sizes and materials such as aluminum, copper, vinyl or steel.

One advantage of conventional gutters is their affordability compared to other types of drainage systems. They are also easy to install and maintain with regular cleaning being necessary for optimal performance.

However, one disadvantage is that they can be prone to clogging due to debris buildup such as leaves or twigs falling onto them during heavy rainfall seasons. This can lead to water overflow which may cause damage not only on your roofing but also on walls and foundation if left unattended.


They are typically used in flat or low-slope roofs and consist of an opening in the wall or parapet that allows water to drain off the roof. Scuppers work by allowing rainwater to flow over the edge of the roof and into a downspout, which then carries it away from the building’s foundation.

One advantage of scuppers is their simplicity – they don’t require any moving parts or mechanical components, making them less prone to failure than other types of drainage systems. Scuppers can be more aesthetically pleasing than traditional gutters since they blend seamlessly with a building’s design.

However, there are some downsides to using scuppers as well. For one thing, they may not be suitable for areas with heavy rainfall since they have limited capacity compared to conventional gutters.

Also, if not installed properly or maintained regularly, debris such as leaves and twigs can clog up scupper openings leading to water damage issues.

Inner Drain

It consists of a network of pipes and channels that are placed beneath the roofing material, allowing rainwater to flow directly into them. This system is ideal for buildings with flat or low-sloping roofs, where water tends to accumulate easily.

One advantage of an inner drain system over conventional gutters or downspouts is its aesthetic appeal. Since it’s hidden from view, it doesn’t detract from the building’s appearance like other systems might.

Another benefit of an inner drain system is its ability to handle large volumes of water quickly and efficiently. The pipes used in this type of drainage can be larger than those used in traditional gutter systems, which means they can handle more water without overflowing.

However, installing an inner drain requires careful planning and expertise since it involves cutting through the roof membrane itself. Therefore hiring professional contractors who specialize in this kind installation will ensure proper installation without damaging your property.

Siphonic Drain

Unlike conventional gutters, which rely on a slope to direct water towards downspouts, siphonic drains use negative pressure to create suction and pull water through pipes at high speeds.

This innovative system is ideal for large commercial buildings or properties with flat roofs because it can handle larger volumes of rainwater without overflowing. It also requires fewer downspouts than traditional gutter systems, making it more aesthetically pleasing.

However, installing a siphonic drain requires specialized knowledge and expertise. The design must be carefully calculated based on factors such as roof pitch, size of the building’s footprint, and local rainfall patterns.

Improper installation can lead to leaks or inadequate drainage capacity.

If you’re considering installing a siphonic drain for your property’s roofing needs, consult with an experienced professional who specializes in this type of system before making any decisions.

Box Gutters

They are designed to be integrated into the roof structure, creating a seamless look that blends in with the building’s architecture. Box gutters can handle large volumes of water and are ideal for areas with heavy rainfall.

One advantage of box gutters is their durability. Made from materials such as copper, aluminum or steel, they can withstand harsh weather conditions without rusting or corroding easily.

However, one disadvantage of box gutters is that they require regular maintenance to prevent clogging and ensure proper drainage flow. Leaves, debris and other particles can accumulate inside them over time if not cleaned regularly.

If you’re considering installing box gutter systems on your property or need help maintaining an existing system, it’s important to consult with roofing professionals who have experience working with this type of gutter system.


They collect rainwater and channel it away from your home’s foundation through downspouts. Eavestroughs come in various materials such as aluminum, copper or vinyl and can be customized to fit any building’s design.

One advantage of eavestroughs is their ability to handle large volumes of water during heavy rainfall. This helps prevent water damage to your property by directing it away from vulnerable areas like basements or crawl spaces.

However, eavestrough maintenance is crucial for them to function properly. Leaves and debris can accumulate in the trough over time causing blockages which lead to overflowing gutters during rainfall – defeating their purpose entirely! Regular cleaning will ensure they remain clear so that they continue working efficiently.

Roof Overflows

This is where a roof overflow comes in handy. A roof overflow is an additional outlet that allows excess water to escape when gutters and downspouts become clogged or cannot handle the volume of rainwater.

Roof overflows are typically installed at strategic locations on a flat or low-sloped roof, such as near parapet walls or scuppers. They work by providing an alternative path for water to flow off the rooftop and prevent it from pooling up and causing damage.

It’s important to note that while a roof overflow can be helpful during heavy rains, it should not be relied upon as a primary means of drainage. Regular maintenance of your gutter system will help ensure proper functioning during normal weather conditions and reduce reliance on emergency measures like overflows.


They are responsible for carrying water from the gutters or scuppers down to the ground, where it can be safely channeled away from your property’s foundation. Downspouts come in a variety of sizes and materials, including aluminum, copper, vinyl and steel.

When choosing a downspout for your building’s roof drainage system, it is important to consider factors such as rainfall intensity and volume. A larger diameter downspout may be necessary if you live in an area with heavy rainfall or have a large roof surface area.

It is also important to ensure that your downspouts are properly installed and maintained. Clogs caused by debris buildup can lead to water damage on both the exterior and interior of your property.

Regular cleaning will help prevent clogs while ensuring that rainwater flows freely through the gutter system.

Rainwater Harvesting Systems

These systems collect rainwater from the roof and store it in a tank or cistern, where it can be used for irrigation, flushing toilets, or even drinking with proper filtration. Not only does this help save on water bills, but it also reduces the demand on municipal water supplies.

When considering a rainwater harvesting system for your building’s roof drainage needs, there are several factors to consider such as the size of your property and how much rainfall you typically receive in your area. It is important to consult with an experienced roofing contractor who specializes in these types of systems before making any decisions.

Seamless Gutters

Unlike traditional gutters, which are pieced together from multiple sections, seamless gutters are made from a single piece of material that is custom-fit to your roofline. This means that there are no seams or joints where leaks can occur, making them more durable and less prone to damage.

In addition to their durability, seamless gutters also offer aesthetic benefits. They come in a variety of colors and materials so you can choose the perfect match for your home’s exterior design.

When it comes to installation, seamless gutter systems require professional installation by an experienced roofing contractor who will measure and cut the gutter on-site using specialized equipment. While they may be slightly more expensive than traditional sectional gutter systems upfront due to their custom nature, they often prove cost-effective over time as they require less maintenance and repair work.

Leaf Guards

They prevent leaves, twigs, and other debris from clogging up your gutters or downspouts. This not only ensures that water flows freely through the system but also reduces the risk of damage to your roof caused by overflowing water.

There are several types of leaf guards available on the market today, including mesh screens, foam inserts, and gutter covers. Mesh screens are made from a fine wire mesh that fits over your gutters or downspouts to keep out debris while allowing water to flow through easily.

Foam inserts work similarly but use a porous foam material instead of wire mesh.

Gutter covers come in various shapes and sizes but all serve one purpose: keeping leaves out! Some models snap onto existing gutters while others require professional installation.

Gutter Materials

Gutter Maintenance

Gutters can become clogged with leaves, debris and other materials over time. This can cause water to overflow and damage your property’s foundation or even the roof itself.

To prevent this from happening, make sure that you clean your gutters at least twice a year – once in the spring and again in the fall. You may need to clean them more frequently if there are many trees around your property.

When cleaning gutters, use gloves and safety goggles for protection against sharp objects or insects that may be hiding inside them. Remove any debris by hand or using a scoop tool designed for gutter cleaning.

Inspect gutters for leaks or damage while cleaning them; repair any issues as soon as possible before they worsen over time.

Roof Pitch and Drainage

The slope of the roof determines how quickly rainwater will flow off and away from the structure. A steeper pitch means that water will move more quickly, which can be beneficial for preventing pooling or standing water on the surface.

However, it’s important to note that not all roofing materials are suitable for steeply pitched roofs. For example, some types of shingles may not adhere properly or could become damaged in high winds if installed on a steeply sloped roof.

Conversely, flatter roofs require different types of drainage systems than those with steeper pitches. Flat roofs tend to collect more debris and can be prone to leaks if proper drainage isn’t established.

When selecting a roofing material and corresponding drainage system, it’s essential to consult with an experienced professional who understands these nuances and can recommend appropriate solutions based on your specific needs.


What are the drains from the roof called?

The drains from the roof are called roof drainage systems, which consist of a gutter system and downspout.

What are the different types of roof drainage systems available?

Types of roof drainage systems include: gutter system, inner drain system, scupper drain system, and drip edge drain system.

How do roof drainage systems prevent water damage to buildings?

Roof drainage systems prevent water damage to buildings by collecting and directing rainwater away from the structure, ensuring minimal moisture seepage and erosion.

What are the essential components of an effective roof drainage system?

An effective roof drainage system consists of essential components such as gutters, downspouts, roof drains, and scuppers, which work together to prevent water damage and maintain structural integrity.