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Specification

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Systems We Supply

Independent, so the recommendation can follow the building

We are not a single-supplier installer. We specify across leading UK and European system houses, which means the answer to your project is not decided before we arrive.

Why the system matters

Two aluminium sliding doors can look almost identical in a photograph and behave completely differently in a Cumbrian winter. Maximum sash weight, interlock width, drainage design, thermal break geometry and the ability to adjust the door in ten years' time are all set by the system, not the colour.

These are the ranges we specify most often, and the situations each one earns its place in.

Specification data

Every system, in full technical detail

Sightlines, maximum sizes and weights, thermal and weather-test performance, threshold options and structural notes — expandable below so the page stays readable for homeowners and complete enough for architects to specify from.

01

Cortizo

Ultra-slim sliding and minimal-frame glazing

Spanish-engineered and now one of the most specified names in UK minimal glazing. Cor Vision allows frames to disappear into the surrounding structure so the glass reads almost edge to edge — the system we reach for when the architecture is the brief.

Where it excels
25mm central interlocks, sashes to 4000mm and up to 94% glazed area
Systems we specify
COR Vision minimal sliders · COR Vision Plus · Corner pocket systems
Minimal-frame corner pocket sliding glazing
Ultra-slim corner sliding door detail
Slimline slider open onto a Cumbrian garden

Systems in the range

COR Vision

Minimal sliding

The standard minimal slider: 20mm central interlock, frames buried into floor, ceiling and reveals so only glass is visible from inside the room.

Central interlock
20mm
Max sash
2500 × 3000mm
Max sash weight
320kg
Uw
From 1.1 W/m²K
Configurations
2, 3 and 4 track, corner and pocket options

COR Vision Plus

Large-format sliding

The large-format development of Cor Vision, engineered for panoramic openings with fully embedded perimeter frames and a glazed surface of up to 94%.

Central junction
25mm
Max sash height
Up to 4000mm
Max sash weight
Up to 400kg (manual)
Glazing capacity
Up to 56mm
Uw
From 0.9 W/m²K (glass dependent)
Alloy
6063 T-5 with polyamide thermal break

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

02

Alunet

The Aluna range — architectural aluminium, engineered in the UK

Alunet's Aluna range covers windows, bifolds and sliding doors on a single visual language, which makes it our default when a whole elevation — or a whole house — needs to read consistently. Slim sightlines, concealed drainage and marine-quality powder coating, supported by short UK lead times.

Where it excels
25mm slider interlocks, 2.5 × 2.7m sashes and triple-glazed U-values from 0.9 W/m²K
Systems we specify
Aluna sliding doors · Aluna bifolding doors · Aluna+ windows · Aluna windows
Alunet heritage bifold doors in Lancaster
Alunet bifold doors open onto a terrace
Five-panel Alunet bifold doors on a cottage extension
Slim aluminium Aluna windows on a Cumbrian elevation

Systems in the range

Aluna Sliding Doors

Slimline slider

Ultra-modern slimline patio door available with 25mm or 50mm interlocking sightlines, engineered for large glass with a very quiet, weighted action.

Interlock sightline
25mm or 50mm
Max sash
2500 × 2700mm
Max sash weight
250kg
Uw
From 1.4 W/m²K
Configurations
2, 3 and 4 panel, 2 and 3 track, corner options
Security
PAS 24:2022 tested

Aluna Bifolding Doors

BF73 development

A refinement of the proven BF73 folding system with 107mm sightlines, running gear rated for daily use and open-in or open-out configurations up to seven panels.

Sightline
107mm
Max sash
1200 × 3000mm
Uw
From 1.1 W/m²K triple glazed
Glazing
28mm double or 44mm triple
Threshold
Weathered, low-profile or flush
Finish
Marine-quality powder coat, dual colour available

Aluna+ Windows

75mm profile

The premium window in the range: a 75mm frame with a super-slim sash, concealed drainage with no visible caps, and clip-in 'click and forget' beads.

Frame depth
75mm
Uw
1.3 W/m²K double / 0.9 W/m²K triple
Drainage
Fully concealed, no external drainage caps
Glazing
28mm double or 44mm triple, clip-in beads
Styles
Casement, flush casement, tilt and turn, fixed lights

Aluna Windows

73mm / 81mm

The core window system in 73mm or 81mm outer frame depths, including heritage and flush options for period elevations and conservation areas.

Outer frame
73mm or 81mm
Uw
From 1.4 W/m²K
Energy rating
WER A
Styles
Standard casement, flush casement, heritage
Security
Multi-point espagnolette locking, PAS 24 achievable

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

03

Smart Systems

Britain's most widely used aluminium range

Long established, comprehensively tested and supported by a national supply chain. Smart covers the middle ground properly: strong thermal figures, sensible sightlines and hardware that can be serviced for decades rather than replaced.

Where it excels
Proven detailing, national parts availability and heritage-appropriate profiles
Systems we specify
Visoglide Plus · Invisoglide · Visofold 1000 bifolds · Alitherm Heritage
Slimline aluminium sliding doors near Carlisle
Aluminium sliding doors on a brick extension
Aluminium bifolding doors in Bowness

Systems in the range

Visoglide Plus

Sliding

The workhorse slider: extended polyamide thermal breaks, robust running gear and configurations up to four tracks for commercial-scale openings.

Uw
1.6–1.4 W/m²K depending on glass
Tracks
2, 3 and 4 track
Glazing
Up to 40mm, double or triple
Threshold
Standard, low or flush with drainage

Invisoglide

Bonded slider

The bonded-glazing development of Visoglide, giving noticeably slimmer sightlines and enhanced security through structural adhesive rather than beading.

Glazing method
Structurally bonded sash
Sightlines
Slimmer than standard Visoglide
Security
Enhanced by bonded construction, PAS 24 achievable

Alitherm Heritage

Windows

A steel-look casement window designed for period and conservation properties, with slim frames, putty-line detailing and true Georgian bar options.

Appearance
Steel-look, slim sightlines, putty-line profile
Bars
True horizontal and vertical astragal bar options
Uw
From 1.4 W/m²K
Use
Conservation areas and listed-adjacent elevations

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

04

Alumil

Precision-engineered European profiles

Newer to the UK, with a long international record on architect-led buildings. The AB-38 remains one of the slimmest bifolds available here, with an 88mm glass-to-glass sightline where panels meet, and the SMARTIA range covers windows and lift-and-slide at genuinely architectural specification.

Where it excels
88mm bifold sightlines with 1300 × 3000mm panels
Systems we specify
AB-38 slimline bifolds · SMARTIA S560 lift and slide · SMARTIA S67 tilt and turn
Slimline bifold doors on a clad garden room
Bifold doors on a brick extension
Architectural aluminium glazing in Kirkby Stephen

Systems in the range

AB-38

Slimline bifold

The slimmest bifold we specify: an 88mm glass-to-glass sightline at the meeting stiles and matching 44mm-frame single and double doors.

Sightline
88mm glass to glass
Max panel
1300 × 3000mm
Max sash weight
140kg
Uw
1.1 W/m²K (with 0.6 centre pane)
Glazing
28mm to 44mm
Matching doors
Single and double doors with 44mm frames

SMARTIA S560

Lift and slide

A robust lift-and-slide system for large, heavy sashes where the door needs to feel effortless despite its size.

Operation
Lift and slide or standard sliding
Use
Large-format panoramic openings
Thermal break
Multi-chamber polyamide

SMARTIA S67

Tilt and turn

A 67mm tilt-and-turn window system with a concealed-sash option that reduces the visible aluminium face to 72mm.

System depth
67mm
Uw
From approximately 1.45 W/m²K
Visible face
93mm, or 72mm with concealed sash
Max glass
Up to 58mm

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

05

The Residence Collection

The credible timber alternative

Where painted joinery is the visual language but maintenance is not welcome. R9, R7 and R2 replicate nineteenth-century timber proportions with mechanically jointed corners, deep sculpted profiles and genuine heritage colourways.

Where it excels
Flush casements and sashes to 0.79 W/m²K triple glazed
Systems we specify
Residence 9 · Residence 7 · Residence 2
Residence 9 windows on a conservation-area property
Residence 7 flush casement windows in grey
Residence 2 windows on a contemporary elevation

Systems in the range

Residence 9

R9 — 100mm

A nine-chamber 100mm system designed to replicate 19th-century timber joinery: flush outside, decorative moulded inside, mechanically jointed corners.

Frame depth
100mm, nine chambers
Uw
From 1.2 double / 0.8 triple glazed
Energy rating
A+ as standard
Styles
Flush casement, mock sash, bays, shaped and arched heads

Residence 7

R7 — 75mm

Flush inside and out on a seven-chamber 75mm profile — the quieter, more contemporary member of the collection.

Frame depth
75mm, seven chambers
Appearance
Flush internally and externally
Uw
From 1.2 W/m²K double glazed
Styles
Casements, shaped and bay windows, single and French doors

Residence 2

R2 — 100mm

The aluminium alternative: a flush sash exterior with a square-cut internal shape and equal glass sightlines throughout.

Frame depth
100mm
Uw
From 0.79 W/m²K triple glazed
Energy rating
Up to A++
Appearance
Square-cut internal shape, equal sightlines

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

06

Timber Look Vertical Sliding Sash

Authentic sash movement, engineered in timber-look uPVC

A dedicated vertical sliding sash system for period and conservation-sensitive elevations. Deep bottom rails, run-through horns, slim meeting rails and fully grained sash faces give the read of painted joinery, while spiral balances, tilt-in cleaning and multi-chamber thermals give the building the performance a modern specification requires.

Where it excels
Both sashes tilt in for cleaning; A+ rated with authentic heritage sightlines
Systems we specify
Vertical sliding sash windows · Georgian and astragal bar sashes · Bay and arched-head sash groupings
Timber look vertical sliding sash windows in heritage cream
Vertical sliding sash window in a stone cottage elevation
Woodgrain sash profile and sloped external sill detail

Systems in the range

Vertical Slider

VS — timber-look uPVC

The core system: two independently operating sashes on spiral balances within a multi-chamber outer frame, with mechanically detailed sash faces and a grained finish inside and out.

Frame depth
Multi-chamber outer frame, deep sculpted sash sections
Operation
Twin spiral balances, both sashes tilt inward
Uw
From 1.2 W/m²K double, 0.9 W/m²K triple glazed
Energy rating
A+ available
Glazing
24–44mm units, warm-edge spacers, laminated options

Heritage Detailing

Sash proportions

The details that decide whether a replacement sash reads correctly from the pavement — specified per opening rather than as a standard product.

Sash horns
Run-through and stub horn options
Meeting rail
Slim mid-rail to hold authentic sightlines
Bars
Georgian, astragal and duplex bars, internal and external
Bottom rail
Deep bottom rail matching period joinery
Hardware
Monkey-tail, teardrop and fitch fasteners; chrome, brass, black

Shaped and Grouped Openings

Bays, arches, mullioned runs

Sashes coupled into bays, mullioned runs and beneath fixed arched heads, with bar layouts aligned across every light in the group.

Configurations
Single, coupled pairs, three and four-light bays
Heads
Fixed arched, segmental and cambered heads above sliding sashes
Couplers
Structural mullion and transom couplers, colour matched

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

07

Nordic Aluclad

Engineered timber core, powder-coated aluminium cladding

Scandinavian aluclad construction: a solid engineered timber structural frame with a powder-coated aluminium skin clipped to the external face, free to move independently of the timber. The internal reveal reads as joinery; the external face is maintenance-free coated aluminium. Available across windows, entrance doors, French doors and lift-and-slide sliding doors within one frame family.

Where it excels
Uw from 0.8 W/m²K triple glazed with a genuine timber internal face
Systems we specify
Aluclad windows — Classic and Softline profiles · Aluclad entrance and French doors · Aluclad lift and slide sliding doors
Aluclad window with timber internal reveal in a contemporary room
Aluclad lift and slide sliding doors onto a coastal terrace
Aluclad frame corner detail showing timber and aluminium junction

Systems in the range

Aluclad Windows

Classic / Softline

Six opening functions on a common frame family. Classic carries a softly moulded external face for traditional elevations; Softline is square-cut for contemporary work. Both share the timber core, cladding system and performance.

Construction
Engineered Scandinavian timber core, clipped aluminium external cladding
Uw
From 1.2 W/m²K double, from 0.8 W/m²K triple glazed
Opening types
Fixed, side hung, side guided, top guided, tilt and turn, fully reversible
Glazing
Argon-filled double or triple, warm-edge spacer, soft-coat low-e
Glazing bars
Bonded 24mm, 42mm or 60mm with matching internal spacer
Ventilation
Clickvent trickle vents, white, aluminium or dual colour

Aluclad Entrance Doors

Solid leaf, PAS 24

A solid engineered timber leaf with a bonded aluminium outer skin in a made-to-measure frame, single or double, opening in or out, with optional sidelights and toplights.

Leaf
Solid engineered timber core with bonded aluminium skin
Ud
From 1.0 W/m²K depending on glazed area
Security
PAS 24 tested, Secured by Design, triple-point locking as standard
Glazing
Toughened or laminated, clear or obscure, double or triple
Hardware
Stainless pull bars 800mm to full height, or matched lever sets

Aluclad French Doors

Single / double leaf

Externally glazed single or double sets opening inward or outward, with shoot bolts to the slave leaf and sidelights aligned to the same sightline as adjacent windows.

Ud
From 1.1 W/m²K
Configurations
Single or double leaf, opening in or out, optional sidelights
Security
Triple-point locking, laminated glass where accessible
Threshold
Standard or low threshold subject to exposure and linear drainage

Aluclad Sliding Doors

Lift and slide

Two-part and four-part lift-and-slide screens. The handle lifts the panel clear of its seals before it travels, then drops it back onto them — giving a heavy panel light operation and a hard seal when closed.

Ud
From 1.1 W/m²K, triple glazed
Configurations
Two-part or four-part, straight run or bi-parting
Operation
Lift and slide gear, single-handed operation on large panels
Security
Triple-point locking, laminated glass where accessible

Figures are manufacturer system data and vary with configuration, glass specification and size. Project-specific U-values, sizes, weights and threshold details are confirmed in writing at design stage — full technical drawings and datasheets available on request.

Explore

These systems, arranged by what you are trying to achieve

Aluminium Windows

Aluminium Windows

Architectural Aluminium

Timber Look Windows

Timber Look Windows

Timber Look Collection

Timber Look French Doors

Timber Look French Doors

Timber Look Collection

Timber Look Single Doors

Timber Look Single Doors

Timber Look Collection

Sash Windows

Sash Windows

Heritage Sash Collection

Sliding Doors

Sliding Doors

Architectural Aluminium

Bifold Doors

Bifold Doors

Architectural Aluminium

Aluminium Single Doors

Aluminium Single Doors

Architectural Aluminium

Aluminium French Doors

Aluminium French Doors

Architectural Aluminium

Entrance Doors

Entrance Doors

Architectural Aluminium

Steel Look Internal Doors

Steel Look Internal Doors

Internal Steel Collection

Internal Steel Single Doors

Internal Steel Single Doors

Internal Steel Collection

Internal Steel Double Doors

Internal Steel Double Doors

Internal Steel Collection

Internal Steel Sliding Doors

Internal Steel Sliding Doors

Internal Steel Collection

Internal Steel Pivot Doors

Internal Steel Pivot Doors

Internal Steel Collection

Internal Steel Bifold Doors

Internal Steel Bifold Doors

Internal Steel Collection

Nordic Aluclad Windows

Nordic Aluclad Windows

Nordic Aluclad Collection

Nordic Aluclad Entrance Doors

Nordic Aluclad Entrance Doors

Nordic Aluclad Collection

Nordic Aluclad French Doors

Nordic Aluclad French Doors

Nordic Aluclad Collection

Nordic Aluclad Sliding Doors

Nordic Aluclad Sliding Doors

Nordic Aluclad Collection

Systems

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