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4" Round Cast Iron Downpipes

4" Round


Our authentic 101mm / 4" cast iron downpipes have been manufactured in standard sizes using traditional casting methods to fit existing round cast iron rainwater systems.

A downpipe is an essential part of any guttering system and carries rainwater from the roof to the stormwater system, preventing your roof from becoming waterlogged.

The size of the downpipe is measured from the inside diameter of the pipe, which is generally 4" but can vary depending on your roof pitch and location in the country.

The outside diameter of the pipe will be slightly larger than the inside diameter because it needs room to bend around corners etc. So, if you need a new downpipe for your property, it's worth considering replacing it with 4" downpipes. These are larger than standard round downpipes and carry more water without bursting or leaking. They also have a longer lifespan than other types of pipes due to their thicker construction.

The 4" downpipe is a popular choice for guttering and can be made from a range of materials, but you'll specifically find cast iron downpipes at Cast Iron Superstore.

Benefits of 4" Downpipes

While you think about the best size for your downpipes, here is what you didn’t know about the 101mm / 4" downpipe.


Reduces the risk of leaks

A 4" downpipe is less likely to give way in heavy rain, so there's less chance of your home being flooded with water. This is especially important if you live in an area where flooding is common or if you have a high-water table nearby.


Easier installation

A smaller diameter means it will be easier for you to install a 4" downpipe as there will be fewer fittings involved. You'll also save money on labour costs because it won't take as long for someone else to complete the job for you! 


Less Maintenance

A larger diameter downpipe will allow more water to flow through it before clogging up. This means you won't need to clean your drainpipes often, saving time and money. It also means that there is less risk when it comes to blockages caused by leaves or other debris, as they will be able to pass through without clogging up at all!


A Huge Range of 4" Downpipes

We have them all available if you're looking for 4" downpipes. We also provide various rainwater downpipes for listed buildings and heritage cast iron guttering systems or period properties, so you can find the right product for your property regardless of size or style.

Among many other fittings in our selection are:

  • 90-degree elbows - these cast iron downpipe fittings make it easy to change direction and ensure water flows smoothly around corners without any problems.
  • 180-degree elbows - these fittings are also used to change direction, but they allow for 180 degrees of movement, so they can be used in places where space is limited or where there isn't much room for movement.
  • Tees - these are useful when connecting two downpipes or connecting them to other pipes such as rainwater tanks or water butts. They can also be an alternative to the 90-degree elbows if there isn't enough space for one of those fittings.

Things to Consider During Installation

You will need to ensure enough space for the new pipes in your guttering before installing them, as any damage caused by poor installation could lead to further problems later on. 

You may need to replace all of your existing pipes if they have been damaged or become clogged over time, so make sure you find out how much this will cost before making any purchases. 


The Leading Guttering Supplier in the UK

Cast Iron Superstore is the best choice if you are looking for a reliable gutter supplier. We have been in this industry for more than 20 years and have a very good reputation in the market.

Here is what you get from us:


Affordable Prices

We offer competitive prices so that you get the best value for money. You don't have to spend much money buying guttering from us as we have reasonably priced products that won't hurt your pocket.


Timely Delivery

We ensure your order is delivered at the right time without delay. With our efficient logistics department and advanced packaging system, we can deliver your order anywhere in the UK within 3-4 days after placing an order.


Friendly Customer Support

Our experienced customer support team will help you in every step while placing an order or installing the product on your home or office premises. You can contact us anytime; we'll gladly help.


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