3 Types of Aluminium Rainwater Pipes.

What type of aluminium rainwater pipe is best suited to my project? 

Will the type I choose even affect my water system? 

Why are all the options so confusing?!

We know choosing your design of rainwater pipe can seem like a complicated task amongst others in the grand scheme of completing an entire water system. In our 25 years of experience we’ve heard and answered all of these questions, but that’s why we are here to make what can be a complicated decision, one load lighter.

Swaged. Flush joint. Square. What?

In only a matter of minutes these confusing variants of rainwater pipes will become crystal clear as we help to explain the different available types of aluminium rainwater pipes and their benefits and drawbacks.

Aluminium Rainwater Pipe Type Number 1: Swaged Pipes.

Swaged pipes are made through a forging process in which the dimensions of an item are altered using dies into which the item is forced. Essentially, swaging is an easy process that doesn’t require a skilled operator. Thanks to its commonality, swaged pipes have a lowered manufacturing cost and can be readily available for whatever and wherever your project requires. 

Because the process of swaging does not form any chips, no material is wasted in the process, making swaged pipes an extremely cost-effective option.

Thanks to the ease of process in swaging, any material can be used, although aluminium is highly recommended for its durability and non-corrosive attributes given its prolonged exposure to water (not that we are biased). 

Swaged pipes can be highly accurate in their custom design process, allowing you to achieve the bespoke water system you dreamed of. 

Swaged pipes are lightweight and durable, with their material hardness and fixing mechanisms giving excellent rigidity and high impact resistance. Being easy to handle, swaged pipes can be installed by either a specialist, DIY enthusiast or self-builder- the choice is yours!

Ultimately, swaged pipes provide an effective but simple push fit drainage system for modern building design. 

Could they be the perfect rainwater pipe for you?

Aluminium Rainwater Pipe Number 2: Flush joint Pipes.

With flush joint pipes, the ends are specially shaped to form a self-centring joint with an internal jointing space, allowing them to slot into the top of the pipe below. Essentially, the advantage of this design is the clean and uninterrupted line down the length of your downpipe run. 

Compared with swaged pipes which have a noticeable join due to the swaged join being wider than the downpipe diameter, flush joint joins between sections are almost invisible.

Also being a common type of rainwater pipe, flush joint pipes are extremely easy to handle and fix, and can be mounted on brackets to stand clear of the structure. Based on concealed spigots (a small peg or plug), flush joint pipes give a smooth, clean appearance that complements modern building design. 

Is it music to your ears yet?

Aluminium Rainwater Pipe Number 3: Square Flush Joint Pipes.

Offering the same almost invisible join between sections, square pipes are available too.

But does the shape of a pipe really make a difference?

Whilst round pipes are designed for ease of drainage and expulsion, rectangular downpipes are often better suited to the style of homes and can be scaled to different lengths and widths according to your needs. Thanks to their shape, square flush joint pipes have a high tensile strength too.

Square downpipes can be fitted as flush fit downpipes with concealed brackets making it an anti-climb downpipe. If you require vandal resistant downpipes, these are the choice for you!

Compared to other types of pipes, square rainwater pipes require less process, allowing you to remain cost efficient and stick to your budget!


If you are considering bespoke water system solutions, we are here for you!

Aluminium is one of the best materials for manufacturing rainwater and guttering products. Manufactured to a high standard, HJA fabrications can produce any and all aluminium guttering and rainwater products your project demands. 

Not only providing outstanding products and service, we have a 10 year close working relationship with a local coating company who provide coating for aluminium rainwater and guttering products with a 15 year guarantee, coming in an array of colours.

We would be happy to help you achieve a fully matching and integrated water system, package for your next project. Why not contact us here to find out what we can do for you.

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