how to choose the right rainwater system

How To Choose The Right Rainwater System

When choosing the right rainwater system for your project, there is so much to consider from materials, shape, size, and aesthetics. So, when deciding what system is best for you, bear in mind it isn’t just the external appearance of a building that could suffer from the wrong selection, it could affect the fabric of your dwelling too.

With so much to consider, we have compiled a quick guide to make your decision making easier.

Consider the Material Of your Rainwater System:

Whether you are after a sleek metal finish, sturdy traditional look, or a lightweight plastic system, ensure you have all the information to hand.

Cast Iron

Iron is usually the accepted material to be used on listed heritage buildings when a traditional look is seeking to be maintained. Despite being heavier than aluminium, it offers the same durable properties with a 40 year or more life expectancy, but a small amount of maintenance, such as repainting, can extend this.

Cast iron can be customisable relatively cost effectively, to the extent of its joins and bands. You can get stylish rainwater hoppers and decorative ear bands to ensure that the feel of old and historical buildings is reflected.

ultimate specification to aluminium copings


Aluminium offers the same strength and durability of iron, without the excess weight and cost. Due to its lightweight nature, it is increasingly easy to create bespoke solutions to fit your project, whatever it’s requirements. You can adjust and amend with a smooth or textured finish, adding a stylish touch.

You can also have a joint clip fixing method on the gutters which doesn’t require mechanical fixings or welding joints. The fixing method allows your aluminium rainwater system to be installed much more quickly, easily, and cost effectively.

Considering its already low costings, aluminium is 100% recyclable and has a life span of approximately 30 years, which can be extended, like iron, with correct maintenance.


Despite their low cost plastic rainwater systems may end up costing you more money in the long-run, due to maintenance and a short life-span. Whilst they may seem like the go-to if you’re trying to save a little money, it helps to think of the bigger picture: how many times will it need to be replaced? Is it worth the small amount of savings when you consider maintenance costs in the event of damage?

It’s important to remember that metal systems can offer a stylish feel and a longer lifetime guarantee than plastic systems.

Weather/ Environmental Conditions:

You’ll need to consider the environment the system is going into. Is it a heritage or conservation area? You may need to select a material that respects the original character of a property, and reflects the aesthetics.

It is also important to consider the surrounding environment of your rainwater system, is it near the sea or in exposed areas prone to extreme weather? In areas that receive heavy rainfall, stronger more durable materials such as aluminium will be better suited than others.

When snow and ice are a factor, which may only be a problem for a limited period per year in the UK (!), your material selection will be affected. As with any other clogged gutter, added weight can be problematic for the joins and guttering itself, causing them to come loose and requiring repairs later down the line.

However, on the other end of the spectrum, for those rare sunny weeks a year, your rainwater system should retain its good looks when the sun comes out! It should avoid discolouration or cracking when the tempreature rises.

Considering the above, a metal rainwater system is the only way to attain the right combination of hardwearing durability and aesthetic properties than can withstand the factors we have covered.

Shape and Size of Your Rainwater System

Rainwater systems can come in a host of shapes, square, ogee, deep flow and round, so it is fundamental to consider your home or office requirements when choosing the right gutter shape for you and your project.

Consider the capacity of the gutter, the maximum water flow expected, the overall architecture of your home, what material and shape lends itself most to your project?

Just as with shape, size is an important factor. You need to ensure the measurements you or a contractor take are precise, without you’ll run into issues down the line which will cause you to invest in further adjustments to your rainwater systems.

ultimate specification to aluminium copings


With so many considerations, it is easy to get tangled up in the complexities of rainwater systems. That is why we offer expert advice on guidance for projects of all shapes and sizes.

When you choose to partner with HJA, you get access to a personal, yet professional

approach, which is something that we are proud of – and one that has been born out of decades of experience within the Aluminium Fabrication industry.

We are committed to delivering great results and nurturing strong relationships with our clients.

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