Key Takeaways

• Narrow portico staircases in historic public buildings often create significant access barriers for wheelchair users.

• Mosaic landings, uneven risers, side voids, and subterranean vaults all constrain the design of a suitable accessibility solution.

• A bespoke retracting stairlift is often the most heritage-sensitive method of providing access without altering the character of the building.

• Sesame Access offers multiple engineering options to suit short landings, narrow widths, and conservation requirements.

• Fire escape strategy, anti-trespass measures, and pit depth availability all influence product selection.

Introduction

Historic public buildings across central London often feature narrow portico staircases, shallow top landings, deep vaults below, and tight column spacing. These elements make accessibility upgrades appear impossible, especially when conservation considerations apply.

In reality, several engineered solutions can be used to introduce step-free access while preserving the visual integrity of the entrance. A bespoke retracting stairlift is one of the most effective options because it integrates discretely into the existing architecture and keeps the staircase available 99% of the time.

This guide explains the five most common challenges and the six engineered solutions Sesame Access can provide for real-world heritage projects.

5 Key Challenges in Heritage Portico Staircases

1. Short Top Landings and Mosaic Floors

Many entrances feature a very shallow landing depth, often with historic mosaic tiles. This limits the available space for a standard 1400 mm platform and may require a modified 1100 mm configuration with a 90-degree rotation. Mosaic protection or reinstatement must also be managed sensitively.

2. Narrow Stair Width Between Columns

Some entrances provide as little as 1800 mm between columns. After accounting for handrails and safety barriers, the usable space for a lift platform can shrink significantly. This often rules out full-width lifts unless handrail modifications are approved.

3. Left and Right Voids That Create Fall Risks

Spaces beside the staircase can become exposed when stairs retract. These voids must be blocked using rising side barriers or iron railings that move out of the crush zone during lift operation.

4. Sub-Landing Vaults and Fire Escape Routes

Many heritage buildings contain vaults or lightwells beneath the staircase. These may function as fire escape paths or storage areas. Lift frameworks must be positioned so they do not obstruct emergency egress.

The linked Knowledge Hub guide Platform-lifts-fire-alarm-integration explains how modern lifts are connected to building alarm systems and how fire strategies affect product selection.

5. Anti-Trespass Requirements for Portico Areas

Some public buildings need to deter rough sleeping within the entrance. Designs may therefore need to incorporate gates or bifold iron railings that remain clear of the lift’s moving components. These elements must be locked open before the lift activates.

6 Engineering Solutions for Historic Staircases

1. Full-Width Vertically Retracting Staircase Lift

A complete staircase rises to reveal a platform underneath. This solution works when the full width and pit depth can be used. It is ideal for buildings where minimal aesthetic change is required. A good example of this configuration is the Buckingham Listed Building Lift.

2. Horizontal Retracting Stairs with 90-Degree Platform Rotation

Used when the top landing depth is too short for a standard platform. The platform turns 90 degrees to meet the required manoeuvring space. This is commonly applied in entrances similar to those using the Kensington Stairlift.

3. Narrow-Width Lift with Central Handrail Configuration

If the staircase is too narrow to use the full width, a central handrail can replace side handrails. This allows a compact lift platform to operate safely while maintaining user shoulder clearance.

4. Fully Enclosed Platform Lift for Standing and Seated Users

If both standing and seated users require access, an enclosed platform lift may be feasible. This typically needs around 1750 mm clear space from top to bottom riser and careful consideration of pit depth.

5. Dual Side-Barriers for Voids and Fall Protection

Where left and right voids exist, rising barriers can be installed to protect users when the stairs retract. This method has been used in projects similar to the Westminster Equality Act Lift.

6. Full-Area Drop-Down Platform with Mosaic Preservation

In cases where pit depth is sufficient, the entire upper landing—including mosaic flooring—can be engineered to rise and fall as a single assembly. This option keeps the staircase visually unchanged 99% of the time while providing modern accessibility.

The Knowledge Hub article Bespoke Lift Pit Depth Solutions provides further detail on how pit constraints influence this option.

Comparison Table: Which Lift Type Fits Your Heritage Entrance?

Lift Type	Best For	Minimum Space Required	Heritage Impact
Full-Width Vertical Retracting Stairs	Wide entrances, full pit depth available	Full stair width	Very low – stairs remain unchanged
90-Degree Rotating Platform	Short top landings and staircase	1100 mm landing depth	Low – minimal visual changes
Narrow-Width Lift	Very narrow column spacing	800–900 mm usable width	Medium – handrails repositioned
Fully Enclosed Platform Lift	Standing + seated users	~1650 mm for the Westminster	Medium–High depending on enclosure
Dual Side-Barriers	Entrances with voids	Any width; barriers required	Medium – visible safety elements
Full-Area Drop-Down Platform	Sensitive mosaic/heritage floors	Full pit depth + reinforcement	Very low – mosaic preserved

When to Choose Each Solution (Decision Flow)

If your top landing is shallow (<1100 mm):
→ Choose a 90-degree rotating platform.

If the staircase is narrow (<1800 mm column-to-column):
→ Consider a narrow-width lift with central handrail.

If there are voids beside the staircase:
→ Use dual rising side-barriers.

If both standing and seated users require access:
→ Choose a fully enclosed platform lift.

If mosaic preservation is critical:
→ Use a full-area drop-down platform that reinstates the mosaic.

If maximum heritage sensitivity is required with minimal visible change:
→ Choose a full-width vertically retracting stairlift.

Relevant Knowledge Hub Articles

• Platform Lifts Fire Alarm Integration – how lifts interact with fire alarms and building strategies.

• Bespoke-lift-pit-depth-solutions – how pit depth affects lift selection and engineering.

Frequently Asked Questions

Can a retracting stairlift be installed without altering the staircase?

Often yes. Full-width retracting systems allow the existing stairs to rise as one piece with minimal visible change.

Can historic mosaic flooring be preserved?

Yes. The mosaic can be lifted and reinstated or fully integrated into a moveable platform.

Do narrow entrances restrict which lifts can be used?

Narrow entrances require careful modelling but do not rule out retracting stairlift solutions.

Can these lifts support both standing and seated users?

Yes, with an enclosed platform configuration if space allows.

What approvals are needed for a heritage entrance?

Typically conservation input, building control review, pit depth analysis, and fire strategy review.

Call to Action

If you are assessing accessibility options for a historic or architecturally sensitive entrance, book a meeting with our Project Managers:
https://www.sesameaccess.com/book-a-meeting