I mentioned in our ‘Trending’ video that Tier on tier is an old design, 15 - 20 years ago it was popular because louvre blades were small, shutters were narrow and you had to open the shutters to let the light in.
You don't open your shutters...
Now with new modern louvre sizes and wider panels in reality customers don’t open their shutters.
Even customers that have tier on tier, end up leaving them closed most of the time because it ends up being a hassle to close the louvres and hinge them back and they realise that most of the time they do want the privacy from the top half of their window as they are overlooked.
Once the novelty has worn off, and you realise you're not opening them, you end up leaving them closed. This means you’ll have two wide dividing rails where the shutters meet running through the middle of your window blocking out light, so you end up with less light than if you went with a simple full height design in the first place (which is what we recommend)
Bi-folding
In order to make full use of tier on tier shutters, they need to be bi-folded, so 8 shutters in total, 4 at the top, 4 at the bottom, split in the middle so they fold open to each side. However, when you hinge two shutters together, the weight of one shutter pulls down on the other shutter, so in time, the top set of shutters rub on the bottom set, so they become a pain to open, so again, you end up leaving them closed, this is why we recommend a simple full height design.
Tall & narrow
Windows have to be tall and narrow to suit a tier on tier design (like a stable door), if the window is wide and short, it’s totally the wrong shape and look. Splitting the shutters will make your window look even wider.
Traditional sash windows are the right shape and proportions, but these can be old and out of level and twisted, so trying to align 8 shutters so they all line up in the centre can be very tricky and it won't take long before they work their way out of alignment.
Horizontal Tposts
For extra support between the top and bottom tiered shutters, you can choose to use a horizontal Tpost, this is like a section of frame that divides the shutters. This means there will be magnets keeping the shutters closed in the centre of your window and the top set of shutters will have some extra support.
Note: This option is only available for windows that are under 1220mm wide.
So tier on tier can look nice in photos and in magazines but in reality, it's an out of date design, you can get more in your room with larger louvres and just a split tilt.