How to Price Crittall-Style Doors: Labour, Materials and Margin Guide

Summary

"Crittall" is technically a manufacturer's name (W.F. Crittall & Co, founded 1849), but in trade use it has become generic — like "hoover" or "biro" — for slim, hot-rolled or cold-rolled steel-framed glazing with narrow sightlines and visible glazing bars. Genuine steel-framed doors and screens are a distinct product category from aluminium or uPVC: heavier, slower to fabricate, and priced on a completely different basis. Getting this wrong is the single most common pricing mistake on period-property and architect-specified jobs — quoting a Crittall-style door against a standard aluminium bifold rate loses the job to a competitor who understands the product, or wins it at a price that eats the entire margin once corrosion protection, bespoke sizing and lead time are accounted for.

The core cost driver is fabrication, not fitting. A genuine steel door or screen is bespoke-made to size from hot-rolled steel sections (or, for modern ranges, a thermally broken steel composite section), hot-dip galvanised or zinc-primed, then powder coated. Glazing is set into the frame with structural glazing tape or putty-style beading rather than a gasket system. None of this is stock — lead times of 8–14 weeks from a specialist steel fabricator are normal, and that needs to be on the quote in writing before deposit, because clients comparing your price to a standard door supplier's 3-week lead time will otherwise assume you're overpriced.

The second driver is thermal compliance. Traditional non-thermally-broken steel has poor U-values (commonly 3.0–5.0 W/m²K) and will not meet Building Regulations Part L for a standard replacement — it's only acceptable where the property is listed or in a conservation area and a like-for-like match is the accepted route, agreed with the local conservation officer or Building Control before work starts. Modern thermally broken steel ranges close this gap and are the only compliant option for non-listed replacements and new openings. Quoting the wrong spec for the property type is a common and expensive error — always confirm listed status and the compliance route before pricing.

This guide covers genuine steel doors, French door pairs, sliding/folding systems, fixed screens, the aluminium alternative, and a worked example reconciling trade cost to quoted price.

Key Facts

• "Crittall" is a genericised trade term — covers any slim steel-framed glazing, not only the original manufacturer's product; several UK fabricators supply comparable steel systems
• Non-thermally-broken steel U-value — approximately 3.0–5.0 W/m²K; does not meet Part L for standard replacement, only acceptable on listed/conservation like-for-like jobs agreed with the local authority
• Thermally broken steel U-value — approximately 1.4–1.8 W/m²K with double glazing, closer to compliant depending on glazing spec; confirm against the specific system's tested figure before quoting a Part L-compliant job — **** per fabricator's certified data
• Standard Part L whole-door U-value requirement (replacement, existing dwelling) — ≤1.4 W/m²K under Approved Document L1B; genuine non-thermally-broken steel will not meet this
• Lead time — 8–14 weeks from order for bespoke steel fabrication; always confirm with the fabricator per job, never assume stock availability
• Fabrication is the dominant cost — steel doors are 65–80% materials, 20–35% labour, the inverse ratio of many other door types because of the bespoke hot-rolled or thermally broken section fabrication
• Corrosion protection — hot-dip galvanising to BS EN ISO 1461 plus powder coat to BS EN 13438 is the durable specification; primer-only steel will rust within a few years in a UK climate, especially coastal
• Glazing method — structural glazing tape, or traditional putty/bead glazing on heritage-match jobs; putty glazing needs a specialist and adds time
• Ironmongery — heavier-duty hinges and multi-point locking specified for steel sections; standard door hardware often isn't rated for the frame weight
• FENSA/CERTASS notification — replacement external doors are a controlled fitting under Part L; a registered installer self-certifies through FENSA or CERTASS, or the job goes through full Building Control notification
• Listed building consent — required for any alteration to a listed building's fenestration, including like-for-like steel replacement in many cases; always check with the conservation officer before quoting, this is not optional
• Weight — steel sections are significantly heavier than aluminium or uPVC equivalents; factor this into the fitting team size and lifting plan, especially for large screens and sliding systems
• Aluminium "Crittall-look" alternative — powder-coated aluminium with applied or internal glazing bars replicating the steel aesthetic; roughly 40–50% cheaper than genuine steel, achieves modern Part L U-values easily, but does not satisfy listed building like-for-like requirements
• VAT — standard rate 20% on domestic supply and fit; zero-rating only applies in the very limited circumstances covered by new-build or approved alteration rules — **** for any non-standard project before quoting VAT treatment
• Minimum job charge — a genuine steel job rarely makes sense below roughly £2,500–£3,000 once bespoke fabrication, delivery and specialist fitting are accounted for; a single small screen at "trade rate" without covering fabrication setup cost is a common way to lose money on this product

Quick Reference Table

Figures assume a specialist steel fabricator trade account, straightforward existing openings with no structural alteration, and standard vehicle access. Add £350–£900 for a structural engineer if the opening is being enlarged or a lintel/RSJ is required, and £8–£15 per door for FENSA/CERTASS notification. All prices exclude VAT.

Detailed Guidance

Why genuine steel doesn't price like aluminium or uPVC

The instinct on a first look is to price a Crittall-style door the way you'd price any other bespoke door — measure, get a trade quote, add a day rate. That undercharges on two things specific to steel. First, fabrication lead time and setup cost is baked into every steel unit even at trade rates, because nothing is off a shelf; there's no volume-manufactured stock line to fall back on for a rush job, and if a client wants speed you either can't deliver it or you pay a rush-fabrication premium that needs to be quoted separately, not absorbed. Second, weight and handling change the labour profile — a steel door leaf can be 2–3x the weight of an equivalent aluminium leaf, which means a two-person team, careful lifting equipment on larger screens, and longer time to align and pack a heavier frame accurately. Both of these are invisible on a spec sheet and are exactly where underpriced quotes lose money.

Thermally broken vs non-thermally-broken: get the spec right before quoting

This is the single highest-risk area on Crittall-style pricing. Two versions of "a steel door" exist commercially:

• Non-thermally-broken (traditional hot-rolled steel) — the classic Crittall aesthetic, narrowest possible sightlines, but a continuous steel section conducts heat straight through the frame. U-values commonly sit at 3.0–5.0 W/m²K, nowhere near the 1.4 W/m²K Part L1B requirement for replacement doors. This spec is only appropriate where the property is listed or in a conservation area and a like-for-like match has been agreed with the conservation officer as the accepted route around full Part L compliance — get that agreement in writing before ordering, not after.
• Thermally broken steel composite — modern ranges insert a low-conductivity break within the steel section, closing most of the thermal gap while keeping close to the traditional narrow sightline. This is the only steel option that realistically supports Part L compliance for a standard replacement or new opening. Confirm the specific fabricator's tested U_w figure — don't assume, because thermal-break performance varies significantly by system.

Quoting the non-thermally-broken option on a non-listed job, or on a new opening rather than a heritage match, is a compliance failure that will fall over at Building Control notification. Confirm the property's listed status and the compliance route in the first site visit, before pricing.

Fixed screens, French doors and full glazed walls — pricing the combinations

Crittall-style jobs rarely stop at a single door. The common architect-led spec is a door flanked by fixed glazed screens forming a full glazed wall — kitchen extensions and garden-room links are the classic use case. Price these as their true combined scope, not a discounted bundle of the individual line items, because the labour doesn't scale down: a wider opening means more structural consideration (a steel lintel or RSJ is common where the opening exceeds standard sizes — budget £350–£900 for a structural engineer's calculation, separate from the door price), more panels to align square to each other, and a longer single continuous fitting day rather than two shorter ones. A full glazed wall combining a French door pair with two side screens should always price above the French doors alone and above any individual screen — if your combined quote comes out cheaper than the door pair on its own, the sums are wrong.

Corrosion protection and finish — don't let this get value-engineered out

Steel rusts. The entire durability of a genuine steel door rests on the corrosion protection spec, and it's the first thing a client or a competing quote will try to cut to save money. Hot-dip galvanising to BS EN ISO 1461 followed by powder coating to BS EN 13438 is the durable UK-climate specification; primer-and-paint-only steel will show corrosion at cut edges, weld points and fixing holes within a few years, faster in coastal or exposed sites. Quote the galvanised spec as standard and be explicit in writing if a client insists on a cheaper primer-only route — that's a decision they need to own, not one that should be silently substituted to hit a lower headline price.

Aluminium "Crittall-look" as the value alternative

Where budget won't stretch to genuine steel, or the property isn't listed and there's no heritage-match requirement, aluminium systems replicating the narrow-sightline, glazing-bar aesthetic are a legitimate and increasingly common alternative. They're roughly 40–50% cheaper, achieve modern Part L U-values without a thermal-break compromise, and fit and handle like a standard aluminium door — no special lifting plan, standard lead times. The trade-off is authenticity: a conservation officer will not accept aluminium as a like-for-like match for genuine steel windows on a listed building, and a trained eye can tell the difference at close range (steel sections are genuinely thinner than an aluminium replica can achieve while remaining structurally sound). Set the client's expectation on this distinction before they choose — it avoids the awkward conversation after installation.

Worked example: single thermally broken steel door

• Trade supply (door leaf + frame, thermally broken, double glazed, powder coated, ironmongery): £2,800
• Fitting labour — 2 fitters × 1.5 days × £280/day: £840
• Consumables (sealants, glazing tape, flashing): £150
• Disposal of old door/frame: £80
• Total cost: £3,870
• Margin at 30%: £3,870 × 1.30 = £5,031
• Quoted price: approximately £5,000, near the lower end of the £4,850–£6,200 table row.

For the French door pair: trade supply £5,200, labour (2 fitters × 2 days × £280) £1,120, consumables £220, disposal £100 — total cost £6,640, margin at 30% gives £8,632, quoted around £8,600, near the lower end of the £8,300–£10,500 table row.

Frequently Asked Questions

Do I need FENSA or CERTASS for a Crittall-style door?

Yes, if it's a replacement external door in an existing dwelling — it's a controlled fitting under Building Regulations Part L, the same as any replacement door. A FENSA or CERTASS-registered installer self-certifies the work; if you're not registered, the job needs full Building Control notification instead, which adds cost and time to the programme. Check the fabricator's registration status before quoting, as not every specialist steel fabricator is a registered Competent Person Scheme installer.

Can I fit non-thermally-broken steel on a non-listed property?

Not compliantly for a standard replacement. Non-thermally-broken steel typically won't achieve the 1.4 W/m²K Part L1B requirement, so it will fail Building Control notification on a straightforward replacement. It's only appropriate where listed building or conservation area status makes a like-for-like heritage match the accepted route — and that route needs to be agreed with the conservation officer or Building Control in writing, not assumed.

Why is the lead time so much longer than a standard door?

Because nothing is stock. Every genuine steel door or screen is fabricated to the specific opening size from raw sections, galvanised, powder coated and glazed as a bespoke unit. 8–14 weeks is normal for a specialist fabricator; putting a standard 3–4 week lead time on a quote for genuine steel will set an expectation you can't meet.

Is the aluminium "Crittall-look" alternative acceptable to a conservation officer?

Generally no, for a listed building where the original glazing was genuine steel. Aluminium replicas achieve a similar look but cannot match the true sightline width of steel, and conservation officers assessing like-for-like replacement will usually require genuine steel (or, on some heritage-grade ranges, timber). Aluminium is a strong option for non-listed properties or new openings where the aesthetic is wanted without the heritage-match constraint.

What's the biggest way tradespeople lose money on these jobs?

Under-quoting the corrosion protection spec and the structural opening cost. Quoting primer-only steel to hit a lower headline price creates a comeback risk within a few years; quoting a wide opening without a structural engineer's lintel calculation risks a mid-job discovery that adds cost you can't recover once the price is agreed. Both should be scoped and priced explicitly at the first site visit.

Regulations & Standards

• Building Regulations Part L1B (2021, effective 2022) — whole-door U-value ≤1.4 W/m²K for replacement doors in existing dwellings; non-thermally-broken steel typically does not meet this

• Building Regulations Part K — protection from falling, collision and impact in critical glazing locations

• Building Regulations Part Q — security requirements for doors and windows in new dwellings

• FENSA / CERTASS — Competent Person Schemes for self-certifying replacement glazing under Part L; the alternative route is full Building Control notification

• BS EN ISO 1461 — hot-dip galvanised coatings on iron and steel articles; the durable corrosion-protection specification for steel sections

• BS EN 13438 — powder organic coatings for hot-dip galvanised or sherardised steel products

• BS 6375 Parts 1–3 — performance of windows and doors: weather, operation and security

• BS EN 12210 — windows and doors: resistance to wind load classification

• Listed Building Consent (Planning (Listed Buildings and Conservation Areas) Act 1990) — required for alterations to listed buildings, including fenestration replacement — always confirm with the local conservation officer before quoting

• Building Regulations Approved Document L (Volume 1: Dwellings)

• Historic England: Windows advice for historic buildings

• FENSA installer and homeowner guidance

• BSI Group: standards for metal windows and doors

• Planning Portal: listed buildings and conservation areas

• upvc vs aluminium vs timber windows — comparison of mainstream frame materials, useful context for positioning steel against the standard alternatives

• glazing u values explained — full detail on U_w vs U_g and Part L compliance thresholds referenced in this guide

• bifold door pricing guide — pricing approach for aluminium bifold/slider systems, the nearest mainstream comparator product

• patio doors pricing guide — companion pricing guide for standard patio door replacement