July 24, 2024

Everything You Need To Know About Roof Drainage Systems

In this article, we will discuss the importance of roof drainage systems, types of roof drainage, and how you can plan and install a system.

Types of Roof Drainage

Roof drainage systems come in many different types. The most popular are siphonic, green roof drainage design, and conventional roof drainage systems.

Siphonic Roof Drainage Systems: Siphons work by relying on gravity to pull water from the bottom of a steep slope down to a lower point on the same structure.

They are commonly used on flat roofs or those that have relatively small slopes (less than 5 degrees). For example, if you have a cathedral ceiling in your home with no other drains in place, this could be an option for you!

Conventional Roof Drainage Systems: Conventional systems use pumps and pipes to remove excess water from your roof so it doesn’t leak through into your home.

They’re ideal when there’s too much water for siphon action alone or when there’s already an existing drain system in place that needs upgrading (i.e., installing additional pipes).

Green Roofs: Green roofs are another great way to keep moisture away from houses while still allowing them to breathe naturally – through evapotranspiration! There are two main types: vegetated or planted; non-vegetated or bare soil covered with waterproofing membranes.[1]

Conventional Roof Drainage Systems

Conventional roof drainage systems are the most common type of roof drainage system. They’re designed to collect and store rainwater in a tank.

Conventional roof drainage systems are suitable for most buildings, whether they’re residential homes or commercial buildings like offices or restaurants.

This is because conventional roof drainage systems are easy to install, have few moving parts, and don’t require specialist contractors (but you should always check with your local council before installing any kind of system).

Why You Need a Roof Drainage System

Roof drainage systems are important for a number of reasons. They can:

  • Protect buildings and other assets from water damage
  • Protect people from water damage
  • Protect the environment from water damage

Roof Drainage System Design

The design of a roof drainage system is a complex process that can be the difference between a functional and efficient system and one that is prone to clog. The design of your roof drainage system will depend on several factors including:

  • Type of Roof
  • Existing Structural Layout
  • Amount of Soil Onsite

Roof Drainage System Maintenance

Inspect Your System at Least Twice a Year

Inspect your system at least twice a year. This will allow you to spot any damage or signs of leaks before they become an issue, and it will also keep your roof drainage system in good shape for many years to come.

  • Check for any signs of water damage. Look up at the roof and check for signs that the water is leaking through cracks or tears in the pipes, guttering or downpipes. Take note of any stains on ceilings or walls below where these are located.
  • Check for mold growth near gutters and downpipes – especially if they’re damaged by leaves blocking them up which causes water to overflow onto surrounding surfaces creating damp conditions where mold spores thrive (e.g., wallpaper).

Clean the Drains or Gutters

  • Use a hose to clean out debris.
  • Put the end of your hose in your drain and turn on the water. The force of moving water should be enough to dislodge any debris clogging the pipes, but it’s not a bad idea to use an old broom or similar tool if you don’t want to get wet.
  • Use a broom to clean out debris.
  • If you’re looking for something easier than using a hose, try just grabbing a broom and starting at one end of your gutter system and working your way across until everything has been swept away from all openings in both sides of each section (one side is where rainwater drains into, while another is where leaves collect).

Clean the Roof and Downspouts

The roof and downspouts should be cleaned on a regular basis to remove any debris that may have collected there. You can use a hose or pressure washer to clean the roof, and if you need to get into hard-to-reach places, you can use a broom or leaf blower._

Ensure That No Debris Is Clogging the Drain

Step 1: If you do have a clogged drain, use a rake or shovel to remove debris from the drain.

Step 2: Do not use a power tool or other tool that could damage the drain.

Step 3: Do not use a pressure washer to clean the drain.


A well-designed roof drainage system protects buildings, people, and assets from water damage during heavy rainfall.

A roof drainage system is an important part of any building. It’s used to collect and remove rainwater from a roof, and can be integrated into a building’s overall design or installed separately.

A well-designed roof drainage system protects buildings, people, and other assets from water damage during heavy rainfall. A poorly designed one may not only cause damage itself but also exacerbate existing problems with flooding or mold growth.