Staircase Specification Guide for ArchitectsContinox2026-05-06T12:56:30+01:00
For Architects · Specifiers · Developers
Staircase Specification Guide for Architects
Complete NBS-compatible specification clauses for floating, central spine and bespoke staircase systems. BS EN 1090-1 EXC2 manufacturing, BS 6180 balustrade loadings, BS EN ISO 3834-3 welding, Approved Document K compliance. Live engineering reference, production drawings and free CAD/BIM library for UK practice use.
What does Continox specify? Architectural steel staircase systems manufactured to BS EN 1090-1 EXC2 with welding to BS EN ISO 3834-3, glass balustrade systems to BS 6180:2011, all designed to comply with Approved Document K and BS EN 1991-1-1 imposed loads.
What's available for download? NBS-style specification clauses (Q40 stairs, P30 balustrade), structural calculation methodology, full CAD pack (DWG, RVT, SKP, PDF), and live 3D Sketchfab models of representative installations.
Lead time and liability?6–8 weeks from approved design to site delivery. In-house structural engineer signs all calculations. 5-year warranty against manufacturing defect on steel, glass and oak components.
This specification guide is written for architects, structural engineers, contract administrators and developers preparing tender documents or technical schedules for bespoke architectural staircases. It contains the technical specifications, compliance evidence and engineering methodology you need to write a watertight staircase clause — and a free downloadable CAD/BIM pack to drop straight into your project.
All specifications below reflect Continox's standard manufacturing process — verified against an executed production drawing set (V3-ISEBC, Y-Shape Internal Staircase, Cotswolds barn conversion, March 2026) and presented as a live 3D engineering reference further down this page.
Why Architects Specify Continox
Continox is a UK-branded architectural staircase manufacturer with EN 1090-1 EXC2-certified workshops near Kraków, Poland. We provide a single point of accountability — design, structural engineering, manufacture, delivery and installation — with all calculations signed by our in-house structural engineer and full compliance documentation issued for Building Control submission.
The standard alternative to Continox on a UK project is some combination of: a separate joinery firm for treads, a steel fabricator for the structure, a specialist glass installer for the balustrade, a structural engineer for the calculations, and a general contractor coordinating it all. The result is fragmented liability, drawing inconsistencies between trades, longer programmes, and significantly more risk on the architect's professional indemnity policy if something doesn't work on site.
Continox consolidates the entire bespoke staircase package — including the frameless glass balustrade, structural calculations and on-site installation — into one supplier under one contract with one warranty. The architect specifies the design intent; we deliver the engineered, manufactured, installed result.
What This Means for Your Project
Single specification clause covering steel structure, treads, fascia, balustrade and handrail — no inter-trade gaps
Single set of structural calculations covering treads, spine, fixings, balustrade and connections — signed by one engineer
Single CAD/BIM submission — DWG, RVT and SKP files of the as-designed staircase, ready for coordination
Single delivery to site — bracketing, fixings, glass, oak and finished steel arrive together
Single 5-year warranty against manufacturing defect — no finger-pointing between sub-contractors
UKCA marking and Declaration of Performance issued for the assembly under UK Construction Products Regulations
NBS-Compatible Specification Clauses
The clauses below follow standard NBS specification format (Q40 — Stairs, P30 — Glass Balustrade) and are written to be dropped directly into your project specification with project-specific values inserted at the [bracketed placeholders]. Use as drafted, or amend with your own preferred phrasing.
These NBS-style clauses cover the three Continox staircase systems most commonly specified by UK architects: floating (cantilevered), central spine (mono stringer) and bespoke (Y-shape, dual flight, complex geometry). All three share the same structural standards (EN 1090-1 EXC2, BS EN 1991-1-1 imposed loading, Approved Document K dimensional requirements) and differ only in structural arrangement and stringer typology.
Q40/110 Floating Staircase System
NBS Reference · Q40/110 · Floating Staircase
Wall-fixed cantilevered staircase system — open riser, glass balustrade
Manufacturer: Continox Ltd, Gosport, Hampshire — continox.uk
System: Wall-fixed cantilevered floating staircase with concealed steel structure
Steel structure: Hidden steel cantilever bracket assembly fabricated to BS EN 1090-1 Execution Class EXC2; carbon steel grade S275JR; welded in accordance with BS EN ISO 3834-3
Wall fixing: Embedded steel mounting plates, 10mm S275, to suit substrate (solid masonry / reinforced concrete / structural steel frame). Anchor design to BS EN 1992-4
Treads: Solid European Oak [Prime grade], thickness [40mm minimum, 50mm or 80mm available], width [as drawing], finish [Osmo Polyx-Oil / Rubio Monocoat / matt lacquer — to client selection]
Balustrade: Frameless glass balustrade to clause P30/410 below — single side wall-opposite
Handrail: [Solid oak Ø50mm continuous / brushed stainless steel Ø42.4mm] — to client selection
Imposed load: Domestic to BS EN 1991-1-1, Category A — 2.0 kN/m² UDL, 2.0 kN concentrated
Tread cantilever load: Each tread designed for 1.5 kN point load at nosing plus 2.0 kN/m² UDL
Building Regulations: Comply with Approved Document K — rise [≤220mm], going [≥220mm], pitch [≤42°], 100mm sphere rule, headroom [≥2000mm]
Documentation supplied: Structural calculations signed by Continox in-house structural engineer; UKCA Declaration of Performance; CAD/PDF as-built drawings; installation manual; 5-year warranty
Lead time: 6–8 weeks from approved design to site
Indicative price (excl. VAT): from £9,999 — design + manufacture + installation included
Q40/120 Central Spine Staircase System
NBS Reference · Q40/120 · Central Spine Staircase
Mono stringer / central spine staircase — twin-side glass balustrade
Manufacturer: Continox Ltd, Gosport, Hampshire — continox.uk
System: Single central RHS spine beam supporting cantilevered tread plates on both sides
Spine beam: Rectangular Hollow Section RHS 150 × 100 × 5mm to BS EN 10210, carbon steel grade S275JR. Continuous welded assembly per BS EN ISO 3834-3
Tread support brackets (PS1 typology): Trapezoidal welded triangular gussets, each cut from 150 × 100 × 5mm RHS — welded perpendicular to spine at each tread location
Tread mounting plates: 6mm S275 plate, 600 × 198mm, M8 tapped holes for tread fixing
Floor mounting plates: 8mm S275, 280 × 230mm, drilled for M16 chemical anchor (Hilti HIT-HY 200 or equal approved)
Wall connection plates: 10mm S275, 230 × 190mm — only required on landing/turn supports
Treads: Solid European Oak, 105mm thickness, width [920mm or 1000mm], full overlap mortise to bracket — finish [client selection]
Fascia boards: 18mm Solid European Oak — landing edges, matched stain
Balustrade: Frameless glass balustrade to P30/420 below — both sides of flight, both sides of landing
Imposed load: Domestic to BS EN 1991-1-1 Category A; treads designed for 2.0 kN/m² UDL plus 2.0 kN concentrated load
Steel finish: Standard powder coat to RAL [9005 jet black / 7016 anthracite / 7031 blue grey / specifier choice], thickness 60–80μm DFT, pre-treated
Building Regulations: Comply with Approved Document K full requirements
Lead time: 6–8 weeks
Indicative price (excl. VAT): from £10,999
Q40/130 Bespoke Staircase System
NBS Reference · Q40/130 · Bespoke Staircase
Project-specific bespoke staircase — multi-flight, Y-shape, U-shape or complex geometry
Manufacturer: Continox Ltd, Gosport, Hampshire — continox.uk
System: Project-specific staircase fabricated to architect's design intent — typology selected from: dual-flight central spine, Y-shape branching spine, U-shape with intermediate landing, helical or curved spine
Reference project: See V3-ISEBC drawing set (Y-Shape Internal Staircase, Elliott's Barn, Cotswolds — overall height 2828mm, 18 risers + landing, 39.1° pitch, branching dual-flight from central platform) — example of bespoke spec executed by Continox
Structural arrangement: Multiple welded RHS spine assemblies (typically 2–4 sub-assemblies per staircase), joined on site at landing connection plates, each independently calculated and certified
Steel: RHS 150 × 100 × 5mm spines, 6mm/8mm/10mm S275 plates per detail — all to EN 1090-1 EXC2
Treads: Solid European Oak, 105mm thickness — quantities and dimensions per project drawings (V3-ISEBC reference: P1 920×248×105mm ×2, P2 920×278×105mm ×8, P3 1000×278×105mm ×7, Platform 1000×920×105mm ×1)
Balustrade: 17mm toughened laminated glass per P30/420 — quantity, geometry and fixing positions per project drawings (V3-ISEBC reference: 10 panels GP1–GP10, mix of rectangular and trapezoidal cuts)
Fascia: 18mm solid European Oak — to all exposed landing and platform edges
Lead time: 6–8 weeks (longer for highly complex or curved geometry)
Indicative price (excl. VAT): from £12,500 — project-specific quotation following site survey
V3-ISEBC · Reference Bespoke Project
Y-shape branching central spine — RHS 150×100×5mm steel, 17mm laminated glass, 105mm oak treads, 39.1° pitch, Approved Document K compliant
P30 Frameless Glass Balustrade Specification
Continox specifies 17mm toughened laminated glass with PVB interlayer (Saflex / Trosifol) for all bespoke staircase balustrades. This is a material upgrade over the 12mm or 15mm minimum permitted by BS 6180:2011 — providing higher impact resistance and post-breakage retention.
The frameless glass balustrade is the most heavily loaded non-structural element of a staircase. Under BS 6180:2011, it must resist a horizontal line load of 0.74 kN/m for residential use (Category A), or higher for assembly and commercial use. The design must accommodate this load without permanent deformation, with adequate post-breakage performance and an appropriate factor of safety.
Single-side balustrade adjacent to floating staircase
Manufacturer: Continox Ltd
Glass type: 17mm toughened laminated — 8mm toughened + 1.52mm PVB + 8mm toughened
Toughening standard: BS EN 12150-1
Lamination standard: BS EN ISO 12543
Interlayer: Standard PVB (Saflex or Trosifol — equivalent quality)
Heat-soak: Not standard — available as option to BS EN 14179 on project request (recommended for commercial / assembly / public use)
Fixing system: Stainless steel point-fixings (spigots) with 22mm machined holes — drilled in glass per project DXF; 50mm offsets from edge per BS 6180 Annex A
Height: 933mm above pitch line along stair flight; 1100mm above FFL on landings (per Approved Document K — exceeds 900mm minimum for ground-floor landings; 1100mm for any landing above ground floor)
Horizontal load resistance: 0.74 kN/m residential per BS 6180:2011 Table 3 Category A; available to commercial loadings (1.5 kN/m, 3.0 kN/m) on request with upgraded glass spec
Edge treatment: Polished flat-edge (FPE) standard; pencil round or chamfered edge available
Toughening certificate: Issued per panel; CE/UKCA marked
P30/420 Twin-side Frameless Glass Balustrade — Central Spine / Bespoke
Frameless glass balustrade — both sides of central spine staircase
Glass spec: As P30/410 — 17mm toughened laminated PVB interlayer
Geometry: Mix of rectangular panels (along straight flights) and trapezoidal panels (at flight transitions and landings); cuts per project DXF — see V3-ISEBC reference for typical 10-panel set
Mounting on steel spine: Stainless point-fixings welded/bolted to spine assembly — 22mm holes machined in glass per DXF; minimum 50mm edge distance and 70–113mm centre spacing
Mounting on landing/floor: Stainless point-fixings into 100mm screed/concrete with chemical anchor per BS EN 1992-4
Continuity: Glass runs continuously across landing transitions — joints at internal corners only, where mechanical clearance permits
17mm Toughened Laminated · Hole Pattern
Section Detail · 933mm Stair, 1100mm Landing
Structural Engineering & Loading Compliance
Every Continox staircase is structurally designed by our in-house structural engineer against the loads stated in BS EN 1991-1-1, with welded steelwork executed to EN 1090-1 EXC2 and welding controlled per BS EN ISO 3834-3. Calculations are signed and issued as a PDF set with the project drawings.
Imposed Loadings — BS EN 1991-1-1
Use Category
UDL
Concentrated Load
Continox Standard
Category A — Domestic / Residential
2.0 kN/m²
2.0 kN
Standard spec
Category B — Office
3.0 kN/m²
4.5 kN
Available on request
Category C1 — Areas with tables (cafés, restaurants)
3.0 kN/m²
4.0 kN
Available on request
Category C3 — Congregation areas
5.0 kN/m²
4.5 kN
Project-specific design
Category C5 — Susceptible to overcrowding
5.0 kN/m²
4.5 kN
Project-specific design
Balustrade Loadings — BS 6180:2011
Use Category
Horizontal Line Load
UDL on Infill
Concentrated Load
Single-family dwelling — internal
0.36 kN/m
0.5 kN/m²
0.25 kN
Other residential — internal
0.74 kN/m
1.0 kN/m²
0.5 kN
Office, retail, commercial
0.74 kN/m
1.0 kN/m²
0.5 kN
Assembly / public — < 50 occupants
1.5 kN/m
1.5 kN/m²
1.5 kN
Assembly — overcrowding-susceptible
3.0 kN/m
1.5 kN/m²
1.5 kN
Note: BS 6180 distinguishes single-family dwellings (the lowest load) from other residential uses such as flats, HMOs and assisted living — where the higher 0.74 kN/m line load applies. Continox standard glass spec (17mm toughened laminated) covers all categories up to and including 1.5 kN/m with appropriate fixing design; commercial and assembly uses simply require closer fixing centres and confirmation of the worst-case panel spans.
Approved Document K — Dimensional Compliance
Requirement
Part K Limit
Continox V3-ISEBC Reference
Compliance
Maximum rise (private)
≤ 220mm
202mm
✓
Minimum going (private)
≥ 220mm
248mm
✓
Maximum pitch
≤ 42°
39.1°
✓
2R + G formula
550–700mm
652mm
✓
Minimum headroom
≥ 2000mm
2828mm overall
✓
Open riser sphere rule
100mm sphere cannot pass
Verified per drawing
✓
Stair flight width
≥ 600mm domestic
1000mm
✓
Balustrade height — flight
≥ 900mm above pitch
933mm
✓
Balustrade height — landing > 600mm
≥ 1100mm above FFL
1100mm minimum
✓
BS EN 1090-1 EXC2
Steel Manufacturing
All structural steel components manufactured to Execution Class 2 — the standard required for ordinary architectural steelwork in UK Building Regulations. Continox workshop is independently certified.
BS EN ISO 3834-3
Welding Quality Assurance
Standard welding QA — the appropriate level for EXC2 work. Welding procedure specifications (WPS) and welder qualifications (WPQR) maintained in workshop and available on project request.
BS EN 1991-1-1
Imposed Loads
All staircases designed against the imposed load category appropriate to use — Category A (domestic) by default, with commercial and assembly categories available as project upgrade.
BS 6180:2011
Balustrade Loading
All balustrade designs comply with horizontal line load, infill UDL and concentrated load requirements appropriate to the use category. Continox standard glass exceeds residential minimum.
BS EN 1992-4
Anchor Design
Chemical and mechanical anchors to wall and floor substrates designed in accordance with European anchor design standards — appropriate Hilti or equal-approved system per substrate.
Approved Document K
UK Building Regulations
Every staircase complies with rise, going, pitch, headroom, sphere rule and balustrade height requirements. Compliance documented per project on as-built drawings.
Live Engineering Reference · V3-ISEBC
Live 3D Model — Y-Shape Bespoke Staircase
Below is the executed production model for V3-ISEBC (Y-Shape Internal Staircase, Cotswolds barn conversion, March 2026) — the same model referenced by every NBS clause above. Rotate, zoom and section to inspect every connection, weld and tread fixing in browser.
The production drawings below are extracted from the V3-ISEBC drawing set — issued at manufacturing release for the Cotswolds project. They are illustrative of the standard of detail provided to architects and Building Control on every Continox bespoke project. Click any drawing to view full size.
Rise · Going · Pitch · Part K
Spine Engineering · RHS 150×100×5
Component Assembly · 4 Sub-systems
Spine Assemblies 1–3 · MP / TS / TP
Oak Treads · 105mm · 4 Sizes
Y-Shape · Top View · As Installed
Materials & Finishes Schedule
All materials specified below are Continox standard supply. Where a material is project-specific (e.g. RAL colour, stain, glass tint), the choice is the architect's — but the underlying standard, grade and dimension are fixed.
Element
Standard Spec
Reference Standard
Project Variables
Steel — RHS spine
RHS 150 × 100 × 5mm, S275JR
BS EN 10210
Section size scaled per span
Steel — plates
S275 — 6mm / 8mm / 10mm
BS EN 10025
Per detail
Steel finish
Standard powder coat 60–80μm DFT
BS EN ISO 12944 protective
RAL colour — client choice
Welding
MIG/MAG, BS EN ISO 3834-3
EN 1090 EXC2
None — fixed
Treads — timber
Solid European Oak, 105mm thickness, Prime grade
BS EN 14342 (timber flooring)
Stain / lacquer — client choice
Fascia — timber
Solid European Oak, 18mm
—
Stain matched to treads
Glass — balustrade
17mm toughened laminated, 8/1.52 PVB/8
BS EN 12150-1 + BS EN ISO 12543
Tint — clear (standard)
Heat-soak
Not standard — option per BS EN 14179
BS EN 14179
Recommended for assembly use
Glass fixings
Stainless steel point fixings — A2 grade
BS 6180 Annex A
Position per project DXF
Wall anchors
Hilti HIT-HY 200 with M16 / M20 stud
BS EN 1992-4
Selection per substrate
Project Workflow — From Specification to Installation
The Continox workflow is designed to fit cleanly into a UK construction programme — with clear architect deliverables at each stage and fixed lead times from approved design to delivered, installed staircase.
01
Design Brief & Survey
Architect issues design intent — sketches, plans, sections. Continox conducts site survey or works from architect's existing measured survey. Substrate verification critical for floating systems.
Week 1
02
3D Design + Calculations
Continox produces 3D design, structural calculations and fixed-price quotation. PDF drawings issued for architect/client approval. Structural engineer signs off all loads.
Week 2
03
Manufacture
Approved design enters production. Steel cut, welded, blasted, powder coated. Oak machined, sanded, finished. Glass tempered, laminated, drilled per DXF.
Weeks 3–7
04
Delivery & Installation
Single delivery to site — all components, fixings, glass and oak. Continox install team on site 1–4 days. Compliance pack handed over on completion.
Confirm site readiness — substrate finished, access cleared
Installation
RAMS, installation plan, programme
Site induction, access, scaffolding/access equipment if required
Sign-off
UKCA Declaration of Performance, as-built drawings, warranty pack
Receive handover pack — issue for Building Control completion
Free CAD Pack for Architects
CAD / BIM Library — Drop Into Your Project
Free download for UK architects, structural engineers and specifiers. Includes all three Continox staircase systems as production-ready CAD/BIM files plus the executed V3-ISEBC reference set as DWG, PDF and SKP.
DWG — 2D plan, section and connection details (AutoCAD-compatible)
RVT — Revit families with adjustable parameters (rise, going, width)
SKP — SketchUp models for design-stage visualisation
PDF — Production drawing set (V3-ISEBC reference, anonymised)
Download link emailed within minutes — no spam, ever.
Files released under Continox CAD Library Licence — free for use on your live UK projects with Continox-supplied staircase. Not to be redistributed.
Warranty, Insurance & Liability
Continox carries appropriate Public Liability and Product Liability cover for UK contract work. Every staircase is covered by a 5-year manufacturer's warranty against defect. Collateral warranty available for developer projects on request.
Warranty
Every Continox staircase is covered by a 5-year warranty against manufacturing defect — covering steel structure, glass, oak treads and finishes. The warranty applies to the entire installation as a single supplied assembly: there's no division of responsibility between sub-trades. Where a defect arises during the warranty period, Continox attends site, diagnoses and remedies at our cost.
Insurance
Continox carries the following insurance cover, with certificates available for project tender submission:
Public Liability — appropriate cover for UK construction sites
Product Liability — covering supplied product after installation
Professional Indemnity — covering our in-house structural engineer's calculations and design work
Employer's Liability — for our own installation team operating on UK sites
Collateral Warranty
For developer projects, residential schemes, hotel and commercial fit-out, Continox can issue a collateral warranty in favour of funder / purchaser / tenant per JCT or bespoke draft on project request. This is standard practice on schemes above approximately £20,000 contract value and is included at no extra charge. The warranty deed is reviewed and signed before delivery.
Single-supplier accountability — by design. The architect specifies one product; Continox delivers everything inside the package. There's no scenario where the steel fabricator blames the glazier, the glazier blames the joiner, and the architect's PI policy carries the dispute. One supplier, one calculation set, one warranty, one snag list, one signature on the as-built drawings. This is the single most important reason architects specify Continox over assembling the same package from sub-trades.
People Also Ask
The most common questions from UK architects researching specification of bespoke staircases — direct answers below, with deeper detail in the FAQ section.
What execution class do staircases require under EN 1090?
Architectural domestic and most commercial staircases require Execution Class EXC2 — the standard for ordinary structural steelwork. EXC3 is required for highly stressed components (bridges, large spans). EXC4 is reserved for safety-critical structures.
Should glass balustrades be heat-soaked?
Strongly recommended for commercial, assembly and public-access projects per BS EN 14179 — heat-soaking eliminates spontaneous breakage from nickel sulphide inclusions. Continox heat-soaks on project request; not standard on residential.
What is the minimum tread thickness for a cantilever floating staircase?
40mm minimum solid timber for cantilever spans up to 900mm. Below this, deflection exceeds L/300 SLS limit. For 1000mm+ spans, upgrade to 50mm or 80mm. Steel plate alternative: 10mm minimum.
What balustrade load applies to a residential staircase?
Single-family dwelling internal — 0.36 kN/m line load per BS 6180 Table 3. Multi-occupancy residential and other internal — 0.74 kN/m. Public assembly — 1.5 kN/m or higher.
Does Continox provide structural calculations?
Yes — included as standard, signed by Continox in-house structural engineer. Calculations cover treads, spine, fixings, balustrade and connections. PDF set issued with production drawings, ready for Building Control submission.
Can I get a Continox specification clause as a Word file?
Yes — the NBS-style clauses in this guide are available as editable .docx in the CAD pack. Drop the Q40/110, Q40/120, Q40/130 and P30/410, P30/420 clauses straight into your project specification.
Specifier FAQ
Answers to the most common technical and contractual questions from UK architects, structural engineers and contract administrators.
Continox manufactures all architectural staircase steelwork to Execution Class EXC2 — the appropriate class for ordinary architectural steel under UK Building Regulations. EXC2 is sufficient for domestic, multi-residential, office, retail, and most commercial use cases. Welding is controlled per BS EN ISO 3834-3 (standard quality assurance — appropriate to EXC2). For projects requiring EXC3 (high-stress structural components, large spans, bridge-like applications) we can upgrade specification on request — this typically requires welding QA upgrade to BS EN ISO 3834-2.
Yes — every Continox steel staircase carries UKCA marking (and CE marking for projects in EU jurisdictions) under the UK Construction Products Regulations. A Declaration of Performance (DoP) is issued for the assembly stating the harmonised standard (BS EN 1090-1), the execution class (EXC2), the structural characteristics, and the assigned attestation system. The DoP is included in the project handover pack alongside the structural calculations and as-built drawings.
Yes — full structural calculations are included as standard at no extra cost, signed by Continox's in-house structural engineer. The calculation set covers: tread design (cantilever loads, deflection to L/300 SLS), spine beam (bending, shear, deflection), wall and floor anchors (pull-out, shear per BS EN 1992-4), balustrade (line load, infill UDL, concentrated load per BS 6180), and connections. The set is issued as a PDF stamped and dated by the engineer — suitable for Full Plans Building Control submission. We also provide the dimensional compliance schedule against Approved Document K as a one-page summary.
Continox standard is 17mm toughened laminated glass (8mm toughened + 1.52mm PVB interlayer + 8mm toughened) — toughened to BS EN 12150-1, laminated to BS EN ISO 12543. The PVB interlayer is standard quality (Saflex or Trosifol). Heat-soak is not standard — it's available as a project option to BS EN 14179. For commercial projects, public-access buildings, hotels and assembly use we strongly recommend specifying heat-soak: it eliminates the (rare but real) risk of spontaneous breakage caused by nickel sulphide inclusions in toughened glass. Cost premium for heat-soak is small (~5–8%) but the risk reduction for non-domestic use is significant.
Continox is a UK-branded company based in Gosport, Hampshire — with our manufacturing workshop located near Kraków, Poland. The Polish workshop holds the BS EN 1090-1 EXC2 certification issued by an EU notified body, with welding QA per BS EN ISO 3834-3. The full design, structural engineering, project management, delivery logistics and on-site UK installation are all handled directly by Continox UK. The UKCA marking and Declaration of Performance issued for each assembly are valid under UK Construction Products Regulations regardless of manufacturing location, exactly as for any imported architectural steelwork. The standard, calculations and accountability are identical to a UK-fabricated equivalent — the cost advantage is what allows us to offer the architectural specification at our price point.
Standard programme: 6–8 weeks from approved design to delivered, installed staircase. Breakdown: Week 1 — site survey or design brief receipt; Week 2 — 3D design, structural calcs, fixed-price quote issued for approval; Weeks 3–7 — manufacturing (steel fabrication, oak machining and finishing, glass tempering and lamination); Week 8 — single delivery to site, 1–4 days on-site installation. Highly complex bespoke geometry (curved spines, double-helical, multi-storey continuous) may add 1–3 weeks to manufacturing. We confirm a fixed delivery date at design approval — programme certainty is critical for architects coordinating against critical-path floor finishes and decoration.
Yes — collateral warranty is available on request at no additional charge, in favour of funder, purchaser or tenant per the contract requirement. Continox accepts JCT standard form of collateral warranty (CW/F, CW/P&T) as standard, and bespoke draft warranties are reviewed and accepted on most projects. The warranty deed is reviewed during the design stage and executed before delivery. For schemes above approximately £20,000 contract value this is normal practice — issue your draft to us at design stage and we'll return executed before week 8 site delivery.
Both. We quote happily against architect performance specifications (e.g. "open-riser cantilevered staircase, oak treads, frameless glass balustrade, EN 1090 EXC2, Approved Document K compliant, single-supplier package") — selecting our own typology, materials and details to meet the architect's design intent. We equally quote against highly specific tendered specs that name our products by clause reference. The NBS-style clauses in this guide are written to be either dropped in directly or used as a baseline for amendment. We're a contractor, not a product supplier — we expect to quote against the architect's brief, not against a fixed catalogue.
The minimum to issue an indicative quote: floor-to-floor height, total horizontal run, opening width, layout (straight/L/U/Y), preferred typology (floating/central spine/bespoke), and substrate at fixing positions. For a fixed-price quote we typically conduct a free site survey — particularly important for floating designs where wall substrate verification is critical. From an architect's measured drawings we can issue fixed-price quotes for new-build projects ahead of site access, with substrate verification listed as a precondition to manufacture. Lead time from drawing receipt to quote: 2–3 working days.
Yes — full Risk Assessment, Method Statement (RAMS) and any required COSHH documentation issued ahead of site delivery for every project. The RAMS is project-specific (not a generic template) — covering off-loading, vertical handling within the building, anchor drilling and dust control, glass handling, and safe working distances. We accept and complete principal contractor PQQ documentation, RAMS approval cycles and site-specific induction requirements as standard. For commercial projects with CDM principal designer involvement, our RAMS is issued in the project's standard format on request.
The 5-year manufacturing defect warranty is unaffected by client decoration — wall painting, plaster making good, flooring laid up to the staircase, all routine. The only operations that affect warranty are alterations to the structural components themselves (tread replacement, glass swap, anchor re-drilling) without Continox involvement — these would void the warranty on the affected element. For loft conversions or projects where decoration completes weeks after installation, this is normal practice and explicitly anticipated.
Our project portfolio shows a range of recent installations — including the Cotswolds Y-shape barn conversion referenced throughout this guide, plus Kensington central spine, Romsey L-shape floating, Salisbury external steel and others. Reference contacts are made available at design approval stage on commercial and developer projects on request. We can also arrange a workshop visit (Hampshire office or Kraków manufacturing facility) for architects specifying multiple projects.
For UK Architects · Specifiers · Developers
Specify Continox on Your Next Project
Free CAD/BIM library, NBS-compatible specification clauses, in-house structural engineering, EN 1090-1 EXC2 certified manufacturing, full site installation across the UK. Single-supplier accountability with one warranty across the entire package.
