What's the best AOV on the market? You decide...

By Sam Gocher
Wednesday 9th November, 20225 minute to read

What’s the best head of stair AOV on the market? Let’s delve into our RSL-R, or Roof Single Leaf - Residential…

Application & Considerations:


These units are principally designed for smoke and heat ventilation in protected stairwells and corridors within residential apartments, hotels, shops and offices.

RSL-Rs are available in a wide range of sizes to fit your specific project, so if you have an interest in these products, please do visit our Contact Us page. The shape can also differ, be it square, rectangular, or even circular.

The RSL-R will typically be found installed at the head of a stair to meet the 1m2 free area requirement and/or servicing the top floor lobby or corridor areas to meet the 1.5m2 free area requirement.

Now to get into a few of the best features. There are plenty of choices when it comes to deciding on which manufacturer to go with, so if you’d like to learn anything more about what’s been touched on so far, please do feel free to give our friendly team a call.

Whether your system is mechanical or natural, the RSL-R is suitable for either. It’s also effective for other uses, as you can also install it as a roof access provider, or even a hatch to offer natural ventilation.

The RSL-R has a high quality, sleek design and would look good on any residential roof, and to accompany the aesthetic further, there’s the option to powder coat the product in order to match the look of your roof.

Another of our contracting customer’s favourite features on the RSL-R is that you can have the freedom to choose between a curb which needs weathering in with your choice of waterproofing, or if you’d rather, a pre-weathered upstand which comes with a waterproof aluminium flashing.

Specification & Performance:


The product is not only CE marked as standard, but is now UKCA marked to meet new industry guidelines in the United Kingdom.

The RSL-R is also tested to open fully to 160 degrees, which more than meets the legal requirement of 140 degrees. The reason single leaf vents have to open so far is because if your vent opened to say a 90 degree right angle and it was placed on the head of a stair in a natural or mechanical system - wind could come along, hit the leaf and blow smoke straight back down into the building it was being extracted from. This is called negative discharge.

In case you weren’t aware already, we actually have a range of vents designed with louvred blades which also tackle this weather-related issue, but we’ll come onto those in future blog posts.

The RSL-R is certified to BS EN 12101-2, and is tested as a dual-purposed ventilator, meaning it can also be used for day-to-day ventilation as well.

We know how important it is that these products work efficiently, as when there’s an emergency there’s no room for failure. Because of this, Sertus rigorously test the RSL-R. The way we do this is - we run it through 10,000 continuous comfort cycles, which basically means we open and close it 10,000 times to make sure everything is in working order.

Sertus also follow that up with 1000 fire cycles, as we need to make sure they’re reliably operational, in order for them to open when needed.

If you think our product could be effective as part of your project, please don’t hesitate to give us a call. I’ll add a link to our Contact Us page in the description below. I’ll also link below our website page dedicated to the RSL-R in case you’d like to read up on it.

And just one more quick note from me, our RSL-Rs come complete with fixing packs, so you won’t need to worry about sourcing these elsewhere. They also come in a waterproof pouch so weather conditions won’t get in the way. You’ll receive the product and be good to go.

Service Notes:


To round off, it’s important you know how easy it is to find the extra info you need for the RSL-R. You visit sertus.uk - hover over Products and Services, select Single Leaf Vent, scroll down to the downloads section - and you’ll find plenty of information. Be it the Technical Data Sheet, Declaration of Performance, Installation Guide, BIM Model and more. If you need any further help then please do visit our Contact Us page.

The stock availability for our Roof Single Leaf - Residential is extremely strong at generally a 3-7 day wait time and is also a factory controlled product.

If you were to place an order of an RSL-R, they’d be delivered via a dedicated delivery service by our own Sertus vans and also come complete with fixing kits.

If you need help with this or any of our other products then as mentioned, please do Contact Us.

What's the best AOV on the market? You decide...

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