When Should You Use a 45 Degree Saddle Take Off in Spiral Ductwork?
If you’re branching off a spiral duct line, the fitting you choose makes more difference than you may think. A lot of systems still use straight saddle collars by default. These do work of course — but in plenty of situations a 45 degree saddle take off is better suited for the job intended.
45 Degree Saddles have just been added to the Fresh Air Supplies online catalogue, so they’re now available to order in a range of popular duct sizes!
What Is a 45 Degree Saddle Take Off?
A 45 degree saddle take off is a curved galvanised steel branch fitting that sits directly onto your length of round spiral duct. Instead of pulling air off at a hard 90° angle like standard saddles, it brings the branch away at 45 degrees which causes less resistance in the airflow.
The base is shaped to match the curvature of spiral or circular duct, so it sits tight and fixes down easily once you cut your opening.
It’s a simple product but an important one when system performance is key!
Why Pick a 45 degree Saddle Instead of a Straight One (90 degree)?
Straight saddle take offs are common and there’s nothing wrong with them — but they’re not always the most efficient option.
Air doesn’t like sharp turns. A 45° branch gives a cleaner path into the branch duct, reducing resistance and pressure loss.
How to install a 45 degree saddle take off?
Nothing complicated to consider. Just like other duct fittings, you would simply mark and cut the hole on your main length of spiral duct relevant to the saddle size. Sit the saddle onto the duct curve and over the cut hole. Run sealant around the edges and secure further with square or wafer head self drilling screws. Well done, you have just installed a fully sealed and airtight finish 45 degree saddle.
What size of 45 degree saddle take off do I need?
Our 45 degree saddle take offs are sized to match the main duct diameter.
For example:
- 100mm saddle fits a 100mm spiral duct and will give you a 100mm branch from that duct.
- 250mm saddle fits a 250mm spiral duct and will give you a 250mm branch from that duct.
- And so on….
The Bottom Line
If you’re after a neat take-off branch, smooth airflow with less resistance in the system, a 45 degree saddle take off is a smart choice over a standard straight saddle. They are not always required — but when it suits the layout and your intentions, it’s a better performing option!
45 Degree Saddles are now live on the Fresh Air Supplies website. Stocked and available for dispatch.
Not sure of which duct fitting is required for your setup? Get in touch and we will be happy to help wherever we can!
📧 sales@freshairsupplies.co.uk
📞 028 8675 2336