Choose a centre pivot rooflight for a high window fitted mainly for daylight, where the handle at the top and the low price matter more than the view. Choose a top hung where you want an unobstructed view, where the room needs a Part B fire escape window, or where the ceiling is low enough that an open sash would be in the way. The quick rule is sill height: below about 900mm, centre pivot; between 900mm and 1100mm with a view you want, top hung; and any escape room is top hung regardless, because a centre pivot’s pivot bar blocks the opening.
This answer compares the two actions. The escape rules that force a top hung are on loft rooflight fire escape regulations, and how the choice affects daylight is on loft rooflight daylight levels.
How each one opens
A centre pivot rotates on pivots set at the mid-height of the sash. Push the top and the bottom swings out while the top swings in, so the open sash sits half inside the room and half outside, turning on its middle. A top hung hinges at the top and swings the whole sash outward, leaving the entire opening clear, with the handle at the bottom of the sash.
That single difference drives everything else, so it is worth being clear on it before the comparison.
| Factor | Centre pivot | Top hung |
|---|---|---|
| View when open | Interrupted by the sash and pivot bar | Clear, whole opening open |
| Head-height intrusion | Open sash sits in the room at head height | None, sash swings outward |
| Handle position | Top of sash, reachable from a high window | Bottom of sash, needs to be within reach |
| Cleaning outer face | Rotates fully, clean from inside | Most also pivot for cleaning |
| Fire escape suitability | Usually not, pivot bar obstructs | Yes, this is what escape units are |
| Cost | Cheapest, most stocked | 15 to 30 per cent more on the unit |
Where centre pivot wins
The centre pivot is the right choice more often than people think, because a lot of loft rooflights are set high on the slope purely for daylight, and there the pivot’s advantages matter:
- The handle is at the top of the sash, so you can reach it from standing even on a high-set window. On a top hung the handle is at the bottom, which on a high window means a control rod or a pole.
- It rotates fully for cleaning, so you can clean the outer face of the glass from inside, safely, without going near the roof.
- It is the cheapest and most stocked option, so it is quicker to get and easier on the budget.
So for a high daylight window in a loft, a landing, or a bathroom where the view is not the point, centre pivot is usually the sensible spend.
Where top hung wins
The top hung earns its extra cost in three situations:
- You want the view. A top hung opens the whole aperture with nothing across it, so a window set at seated eye level gives a clean view out. A centre pivot always has the sash and the pivot bar across the middle.
- The room needs a fire escape window. This is not a preference. A Part B escape window has to open with a clear route through it, and a centre pivot’s pivot bar obstructs that, so escape units are top hung (or side hung). More on that below.
- Headroom is tight. On a low loft, a centre pivot’s open sash sits in the room at head height and you walk into it. A top hung swings outward and leaves the space clear, so it suits low ceilings and windows near a walkway.
Most modern top hung units also have a secondary centre pivot function for cleaning, so you get the clear opening and the ability to rotate the sash to clean it. That is why, where budget allows and the sill is at a usable height, many people choose top hung for the flexibility.
Fire escape decides it outright
If the rooflight has to serve as a Part B escape window, the choice is made for you. An escape window needs a clear openable area of at least 0.33m², a minimum clear opening of 450mm in both height and width, and the bottom of that opening no more than 1100mm above the floor. A centre pivot cannot usually meet this, because the pivot bar sits across the middle of the opening and breaks up the clear route. Escape units are ordered as top hung or side hung specifically, and they are not something you convert a centre pivot into later. The full escape requirement is on loft rooflight fire escape regulations, and the cost implication is on loft conversion rooflight cost.
The sill-height rule
A simple way to decide, once escape is ruled in or out:
- Sill below about 900mm, high on the slope, daylight only: centre pivot. The handle stays reachable and you are not using the view anyway.
- Sill 900mm to 1100mm with a view you want: top hung. The unobstructed opening is worth the extra.
- Low ceiling or window by a walkway: top hung, so the open sash is not in your way.
- Any escape room: top hung escape unit, no alternative.
- Hard to reach and you want it powered: either, with an electric actuator and rain sensor, covered on electric skylight installation.
We do not steer you to a brand. We fit VELUX, Keylite and Roto and all three make good centre pivot and top hung units. What matters far more than the badge is the action suiting the room, the flashing kit matching your covering, and the collars being fitted. We check the sill height and the escape requirement at survey and recommend the action, not the brand.
Common questions about centre pivot and top hung
Should I choose a centre pivot or top hung rooflight?
Centre pivot for a high window fitted mainly for daylight, where the top handle stays reachable and the low price helps. Top hung where you want a clear view, where the ceiling is low enough that an open sash would be in the way, or where the room needs a fire escape window. The quick rule is sill height: below 900mm, centre pivot; 900mm to 1100mm with a view, top hung; any escape room, top hung.
Can a centre pivot rooflight be a fire escape window?
Usually not. A Part B escape window needs a clear opening of at least 0.33m² with a route through it, and a centre pivot’s pivot bar sits across the middle of the opening and breaks that route. Escape units are ordered as top hung or side hung specifically. You cannot convert a standard centre pivot into an escape window later, so the room’s escape requirement has to be settled before the unit is chosen.
Which is easier to clean?
Both clean from inside. A centre pivot rotates fully so you can reach the outer face of the glass from the room. Most modern top hung units also have a secondary pivot function for exactly this, so you get the clear opening for use and the rotation for cleaning. Neither needs you to go near the roof, which is the point: we never advise anyone up onto a roof to clean a rooflight.
Get the right action specified
Tell us where the window goes, how high the sill will sit, and whether the room needs a fire escape, and we will recommend centre pivot or top hung at survey and give you one written fixed price. Every installation carries a 10-year workmanship guarantee and the installers have 25 years fitting rooflights behind them.
Request a fixed quote for a rooflight in Ipswich, Suffolk or north Essex, or read our published prices first.
Thinking about this job? We survey across Ipswich, Suffolk and north Essex and give you a fixed price before any work starts, with a 10-year workmanship guarantee.