Chartwell Green UPVC Window-design 77

Description

Chartwell Green uPVC Twin Top Light Fixed Window — Classic Proportions, Pure Natural Light

Sometimes the most resolved window design is also the simplest one. Our Chartwell Green uPVC Twin Top Light Fixed Window combines just three fixed panes — two evenly sized top lights in the upper section and a single wide picture pane below — into a composition of quiet architectural authority that brings generous natural light into the room at every level, frames the view without interruption, and delivers the highest possible thermal efficiency through a fully fixed specification throughout.

There are no opening lights here, no handles, no hinges, and no hardware of any kind — just three carefully proportioned panes of A-rated double glazing in a clean, sculpted Chartwell Green frame, held together by a continuous horizontal rail that gives the window its defining divided-light character. It is a design that understands restraint as a form of quality — and that delivers its results through proportion, finish, and specification rather than complexity.

The Divided-Light Principle

The horizontal rail that separates the twin top lights from the wide lower picture pane is the single most important design element in this window — and the element that connects it most directly to the long tradition of divided-light window design in British domestic architecture. From Georgian townhouses to Victorian terraces, from Arts and Crafts cottages to Edwardian villas, the divided-light window — upper lights above a lower picture pane, separated by a continuous transom rail — has been one of the most consistently used and consistently successful window forms in the British built environment.

The reasons for its endurance are practical as well as aesthetic. The horizontal rail divides the frame height into an upper zone and a lower zone, creating a set of proportions that scales naturally with domestic ceiling heights and wall sizes. The upper zone — smaller, lighter in scale — brings natural light to the ceiling and the upper walls without competing with the primary lower pane for visual attention. The lower zone — wider, deeper, more dominant — delivers the primary view and the primary light contribution at the height where both are most directly experienced. The two zones work together to distribute natural light more evenly through the interior than a single undivided pane of the same overall dimensions could achieve.

In our three-light fixed window, this principle is applied with particular clarity. The twin top lights are sized to sit in the correct proportional relationship to the wide lower picture pane — smaller and narrower in apparent scale but spanning the full width through the central divider — creating an upper section that reads as a balanced, considered part of the overall composition rather than an afterthought added above the main glazing.

Twin Top Lights — Upper Zone Illumination

The two fixed top lights in the upper section of this window span the full internal width of the frame above the horizontal rail, divided by a single slim central divider that sits on the same vertical axis as the outer frame elements below. This upper section delivers natural light to the ceiling zone of the room across the complete width of the opening simultaneously — from the left edge to the right edge, without the directional bias of a single light positioned to one side.

Upper zone illumination of this quality has a measurable effect on how a room feels. When the ceiling receives direct natural light from a wide upper source, the room appears taller than it is — the ceiling recedes visually, the upper walls are brighter, and the transition from the naturally lit upper zone to the lower zone illuminated by the wide picture pane below creates a sense of graduated, layered natural light that feels more like the outdoor environment and less like a room with a hole in the wall.

For rooms with standard ceiling heights — where the ceiling can feel oppressively close in poor lighting conditions — this upper zone illumination from the twin top lights is particularly valuable. The wide lower picture pane handles the view and the primary light contribution. The twin top lights handle the ceiling and the upper walls. Together they illuminate the room more completely and more evenly than either could achieve alone.

The single slim central divider between the two top lights is the only vertical element breaking the upper section — and it is sized and positioned to be as unobtrusive as the structural requirements of the 70mm profile allow. In Chartwell Green, the soft sage tone of this divider reads against the clear glazing with a subtlety that makes the upper section feel more open and less divided than a heavier or more prominent central element would allow.

The Wide Lower Picture Pane — The View in Full

The lower picture pane is the centrepiece of this window and the element that determines its suitability for any given opening. Spanning the complete internal width of the frame from the left outer stile to the right outer stile without any vertical division, it presents the outdoor space — garden, landscape, terrace, courtyard, or aspect — as a single continuous horizontal image at the eye level of the room’s occupants.

No central post divides the view. No meeting stile from a pair of casements interrupts the panorama at its midpoint. No fixed light boundary separates the left side of the garden from the right side. The lower picture pane is simply clear A-rated double glazing across the full width, in a slim Chartwell Green border, at the height where the view is most directly and most comfortably experienced.

For wide openings where the outdoor space is worth seeing in its full width — an established garden with planting across its full extent, a rural landscape that extends to both sides of the opening, a rear terrace that runs the full width of the property — this single uninterrupted lower picture pane does justice to the view in a way that a divided lower section cannot. The outdoor space is presented whole, and the room benefits from it wholly.

At the scale this window is designed for, the proportional relationship between the twin top lights above and the wide lower picture pane below is the decisive quality factor — and it is one that our fully sculpted 70mm profile handles with the precision of a frame designed to be seen as well as to perform.

Fully Fixed — The Highest Thermal Standard

A three-light fully fixed window at this width represents the most thermally efficient configuration in the casement window family — and the reason is consistent across all fixed window designs: no moving parts means no degrading seals, no thermal bridging at sash-to-frame junctions, and no mechanical elements that compromise the integrity of the glazed assembly over time.

The 70mm multi-chamber uPVC frame, 28mm argon-filled sealed units, soft coat low-E glass, and warm-edge black superspacer bar deliver a U-value of 1.3 W/m²K across all three panes consistently — the twin fixed top lights and the wide lower picture pane alike. This double glazed uPVC window meets Part L Building Regulations across its full width and delivers genuine, sustained reductions in heat loss from the day of installation through the full lifespan of the frame.

The horizontal rail that runs the full width between the upper and lower sections is the thermally most demanding element at this scale — a continuous frame element with surfaces on both sides of the building envelope. Our 70mm multi-chamber construction maintains sealed air chamber thermal resistance at the rail with the same consistency as at the outer frame elements, eliminating the cold bridge and condensation strip that appear at full-width rails in lesser profiles.

Chartwell Green — Restraint as Character

On a fully fixed window with no hardware and no opening lights, the character of the frame is expressed entirely through proportion, profile quality, and finish colour. Our fully sculptured 70mm profile delivers all three. The moulded edges and shadow lines of the horizontal rail, the central top light divider, and the outer border give the three-light frame a three-dimensional depth that flat-profiled windows cannot achieve — a depth that is most visible at the horizontal rail, where the sculpted edge catches light from above and creates the shadow line that gives the divided-light composition its defining characteristic.

In Chartwell Green, this sculpted profile achieves a quality that is immediately legible as heritage and quality. The soft sage tone runs across the horizontal rail, the slim upper divider, and the outer border with the consistency of a carefully chosen colour that has earned its place in the British window palette over decades of use on every property type from rural farmhouse to suburban semi to city terrace.

The Chartwell Green finish is co-extruded into the uPVC profile, backed by a full 10-year profile guarantee against fading, peeling, warping, and discolouration. These uPVC casement windows require no painting, no maintenance schedule, and no attention beyond an occasional wipe with a damp cloth — across all three panes, the horizontal rail, and the outer frame.

Inherent Security Across the Full Width

All three panes are retained throughout by internal glazing beads — the glass cannot be pushed or levered out from the exterior on any section, including the wide lower picture pane where the glazed area is at its greatest. The fixed outer frame, horizontal rail, and central top light divider form a rigid welded uPVC structure with no hinge gaps, no sash contact zones, and no mechanical entry points across the full width of the opening.

Specification at a Glance

• Energy Rating: A-rated | U-value 1.3 W/m²K
• Configuration: 3-light — twin fixed top lights above a single wide full-width fixed picture pane
• Frame System: 70mm multi-chamber thermally efficient uPVC
• Glazing: 28mm argon-filled units, soft coat low-E glass, warm-edge superspacer
• Hardware: None — fully fixed configuration
• Beading: Internal across all three panes for maximum security
• Finish: Chartwell Green — guaranteed not to discolour, warp or peel
• Compliance: Part L Building Regulations
• Guarantee: 10-year profile guarantee

Made to Your Exact Measurements

• Frame Width: 415mm – 700mm
• Frame Height: 800mm – 2200mm

Every window is manufactured to order to your precise dimensions. Enter your measurements at checkout for a perfect made-to-measure fit. Our team is available for sizing queries and configuration advice before you place your order.

When Proportion, Light and Simplicity Are the Brief

Not every window needs to open. Not every wide opening needs a complex combination of vents, casements, and top lights. Sometimes the brief is simpler and more demanding at the same time — maximum natural light at every level, a panoramic unobstructed view across the full lower width, and a frame that earns its place on the elevation through proportion and finish rather than through complexity and hardware. This twin top light fixed window answers that brief completely. Two fixed top lights illuminating the ceiling zone. One wide picture pane framing the view. A continuous horizontal rail giving the composition its traditional divided-light character. And a sculpted Chartwell Green frame that makes the whole design look as though it was always the right window for this opening. It is one of the most proportionally resolved and thermally efficient designs in our entire Chartwell Green uPVC window range.