How to Architect a £10M Coverage Tower: A Strategic Guide to Primary and Excess Layers

For a corporate risk manager or CFO, constructing a £10 million insurance tower is a familiar, yet increasingly complex, challenge. As single-insurer capacity shrinks, particularly for high-risk sectors, layering coverage seems like the only logical solution. The conventional wisdom is to find a primary insurer, then stack excess layers on top until the required limit is achieved. This approach, however, often treats the process like assembling a set of generic building blocks, ignoring the crucial architectural principles that ensure a tower can actually withstand the pressure of a major claim.

Many advisers focus on the basics: the primary policy, the excess layers, and the general need for ‘follow form’ wordings. But what if the true vulnerability of your risk architecture lies not in the height of the tower, but in the unseen connections between its layers? What if the choice of your lead insurer has more impact on a claim payout than the wording of the 10th excess policy? This is where an architectural mindset supplants mere assembly. It involves understanding the structural integrity of your tower, from the foundation of the primary wording to the load-bearing capacity of each excess layer and the market dynamics that bind them.

This guide moves beyond the basics. We will dissect the engineering behind a resilient coverage tower. We will explore how to strategically manipulate attachment points, analyse the profound impact of market structure on claims, identify hidden gaps in wording, and determine the optimal time to restructure your programme. This is not about stacking blocks; it’s about becoming the architect of your company’s financial resilience.

This article provides a detailed blueprint for constructing a robust insurance tower. Below is a summary of the key architectural components we will explore.

Why Does Your Excess Insurer Only Pay After the First £1M Is Exhausted?

The concept of an excess insurer’s liability only triggering after the primary limit is exhausted seems simple, but it represents the fundamental principle of risk architecture. The primary policy’s limit—whether it’s £1M, £5M, or another figure—acts as your organisation’s initial layer of defence and, often, a significant part of your risk retention strategy. The point at which an excess layer begins to pay is known as the attachment point. This is not an arbitrary number; it’s a carefully calculated threshold below which the excess insurer has zero exposure.

From the excess underwriter’s perspective, their entire business model is predicated on accurately pricing the probability that a loss will breach this attachment point. They are not insuring your everyday claims; they are insuring against severity. Their analysis focuses on the likelihood of large, complex events that completely erode the primary coverage. This is why they scrutinise the primary insurer’s stability, claims-paying history, and the quality of the underlying policy wording so intensely. The primary layer is their buffer against attritional losses.

The importance of this buffer is growing as claim severity trends upwards. For instance, in the complex world of Umbrella and Excess liability, GenRe data shows the severity trend increased dramatically from 3.4% (2009-2019) to 9.3% between 2020 and 2022. This means larger losses are becoming more frequent, putting increasing pressure on higher layers of coverage and making underwriters more sensitive than ever about where their liability begins. The exhaustion of the primary limit is the engineered event that activates their participation.

How to Lower Your Excess Layer Premium by Increasing the Attachment Point?

One of the most direct tools a risk manager has for optimising the cost of their coverage tower is the strategic negotiation of attachment points. The relationship is simple in theory: the higher the attachment point for an excess layer, the lower the premium for that layer should be. By increasing the amount of underlying limit (or self-insured retention) that must be exhausted before an excess policy is triggered, you are fundamentally reducing the insurer’s exposure. You are moving their position further away from the frequency of losses and deeper into severity-only territory.

This is more than just asking for a discount; it is a form of premium arbitrage. You might find, for example, that the cost savings from raising an excess layer’s attachment point from £5M to £6M are greater than the additional premium required to increase your primary limit from £5M to £6M. This creates an opportunity for net savings on the total programme cost without reducing the overall limit. It requires a detailed analysis of your loss history and a market-savvy broker who can model the potential outcomes and negotiate effectively with carriers.

The negotiation is a delicate balance. A higher attachment point signals confidence in your risk management and the stability of your primary layer. It tells the excess market that you are willing to take on more of the “working” part of the risk, leaving them with the more remote, catastrophic portion. This can make your risk profile more attractive and open doors to more competitive pricing from a wider range of carriers, especially in a hardening market.

However, this strategy carries its own risks. You must be completely confident that the underlying layer can fully respond to a loss up to the new, higher attachment point. Any gaps or insolvencies in the lower levels could leave your organisation with an unexpectedly large uninsured loss. Therefore, the decision to increase an attachment point must be coupled with rigorous due diligence on the financial strength and claims-paying ability of all insurers below that point. It’s a strategic lever that must be pulled with precision.

Lloyd’s Lead vs Company Lead: How Does the Market Structure Affect Your Tower?

The choice of lead insurer for your primary or first excess layer is one of the most critical architectural decisions you will make. It dictates not only the initial terms but also the entire claims philosophy of the tower. The two primary market structures you will encounter in the UK are the Company Market (e.g., a traditional insurer like Aviva or Allianz) and the Lloyd’s Market. They operate in fundamentally different ways that have significant downstream consequences.

A Company Market lead provides a single, corporate counterparty. Their claims department operates as a unified entity under a single management structure. A decision is made by ‘the company’. This can offer simplicity and a clear line of communication. Conversely, the Lloyd’s market is a unique ecosystem. As official Lloyd’s data confirms, the market comprises 84 syndicates managed by 51 different managing agents, all operating under one roof. When you have a Lloyd’s lead, you are not dealing with one company but with a specific syndicate (or several) that has taken a share of your risk.

This is where the concept of claims philosophy alignment becomes paramount. The following markets in your tower, whether they are also at Lloyd’s or in the company market, will pay close attention to the actions and decisions of the lead. The lead’s interpretation of the policy wording and their approach to handling a claim sets the precedent.

Therefore, when selecting a lead, a risk manager must ask: do we prefer the single-point-of-contact efficiency of a company lead, or the specialist, collective-but-complex approach of a Lloyd’s syndicate? The answer will depend on the nature of your risks, your desired claims experience, and the overall risk architecture you aim to build.

The Coverage Gap That Appears When Primary and Excess Wordings Don’t Align

The term ‘follow form’ is one of the most reassuring yet potentially misleading phrases in insurance. It suggests that your excess policies will seamlessly and automatically adopt all the terms, conditions, and coverage of your primary policy, creating a perfect, uninterrupted tower of coverage. In reality, the structural integrity of the tower often fails at these connection points. An excess policy may state it ‘follows form’ but then include its own endorsements, exclusions, or different definitions that subtly but critically alter the coverage.

As one analysis points out, this is a common point of failure. LegalClarity.org’s coverage analysis notes:

Follow form sounds like a guarantee of consistency, but gaps between layers are more common than the label suggests.

– LegalClarity.org Coverage Analysis, What Does Follow Form Mean in Insurance Policies?

These gaps can manifest in numerous ways. An excess policy might have a more restrictive definition of ‘occurrence’, a different notice period, or a sub-limit for a specific peril that doesn’t exist in the primary policy. For example, your primary policy might provide a full £5M limit for a certain type of liability, but the first excess layer, attaching at £5M, might introduce a new sub-limit of only £1M for that same liability. In this scenario, you have a £4M gap in your tower for that specific risk. These are the details that can turn a fully-covered claim into a multi-million-pound uninsured loss.

Ultimately, ensuring true alignment requires a painstaking, line-by-line review of every policy in the tower by a broker with deep technical expertise. It is a critical piece of due diligence that validates the architectural soundness of the entire programme. Never assume ‘follow form’ is a guarantee; verify it.

When Should You Restructure Your Coverage Tower: After a Loss or at Soft Market?

The timing of a major restructuring of your coverage tower is a strategic decision that can have significant financial and operational impacts. Too often, this exercise is undertaken reactively, in the chaotic aftermath of a major loss that exposed unforeseen gaps or inadequacies in the programme. While a loss is a powerful catalyst for change, it is often the worst time to be negotiating. The business is under pressure, and insurers are on high alert, potentially leading to more restrictive terms and higher premiums.

The architecturally sophisticated approach is to treat your coverage tower as a dynamic structure that must be reviewed and optimised proactively. The most opportune moment for this is not after a loss, but during a soft market cycle. A soft market, characterised by increased insurer competition and capacity, provides the leverage you need to negotiate favourable terms, broader coverage, and more competitive pricing. It’s an opportunity to fix the roof while the sun is shining.

For example, during a soft market, you can stress-test different tower configurations with your broker. You could explore consolidating layers, increasing limits on certain layers while raising attachment points on others, or introducing new, more favourable carriers into the programme. The market’s appetite for risk is higher, making underwriters more receptive to creative solutions. Recent market trends highlight this window of opportunity; a Risk Placement Services market analysis indicates average rates for E&S property decreased by 5% to 12.5% in Q3 2024, a clear sign of softening conditions that a savvy buyer can exploit.

Restructuring in a soft market allows you to fortify your risk architecture from a position of strength, not desperation. It enables you to lock in multi-year deals, broaden wordings, and build stronger relationships with your chosen carrier partners. This proactive stance ensures that when a hard market inevitably returns—or a major loss occurs—your programme has the structural integrity to withstand the pressure.

Why Does Your Current Policy Leave Critical Gaps Every Time You Expand?

A common frustration for risk managers in growing businesses is the recurring discovery of coverage gaps, especially following an acquisition, a new product launch, or expansion into a new territory. The root cause of this issue is often a fundamental misunderstanding of the nature of an insurance policy. A standard annual policy is not a living, breathing contract that automatically adapts to your evolving business. It is a static snapshot.

As one expert analysis succinctly puts it:

Most standard policies are a snapshot of your business at a single point in time. They are not living documents.

– Insurance Policy Analysis, Understanding Dynamic Business Risk

This static nature creates a significant structural problem. When your business undergoes a material change mid-term, your policy may no longer accurately reflect your risk profile. This triggers a duty to notify your insurers, which presents a strategic dilemma. Do you inform them immediately and risk a mid-term premium hike or the imposition of new restrictions? Or do you wait until renewal and risk having a claim denied because you failed to disclose a material change? This is a classic vulnerability in a non-modular programme.

Without such a framework, every expansion creates a new point of potential failure in the risk transfer mechanism. The policy, designed for the business of yesterday, is ill-equipped to protect the business of today, leaving critical new assets or operations dangerously exposed.

Lloyd’s Syndicate vs Gibraltar-Based Insurer: Which Offers Better Security?

When constructing the lower, load-bearing layers of your tower, the financial security of your chosen insurer is paramount. A £5M primary limit is worthless if the insurer becomes insolvent when a major claim arises. Risk managers are often presented with a wide array of carriers, from major PLC insurers to specialist syndicates at Lloyd’s and, increasingly, carriers based in other jurisdictions like Gibraltar. But how do you compare their security?

The security behind a Lloyd’s syndicate is a unique, multi-layered structure. It is a core part of its value proposition. While each syndicate has its own assets, they are also backed by a “chain of security”. This includes members’ funds held at Lloyd’s and, ultimately, the Lloyd’s Central Fund—a mutual fund of last resort financed by all members of the market. This collective strength is why independent rating agencies confirm that Lloyd’s syndicates carry collective security ratings, such as S&P ‘A+ Strong’ and A.M. Best ‘A Excellent’. You are not just buying the financial strength of one syndicate, but the backing of the entire market.

A Gibraltar-based insurer, or any other standalone carrier, operates differently. Its security rests on its own capital, reserves, and its reinsurance programme. While many are well-capitalised and highly rated, their security structure is a single entity. They are ultimately backed by their jurisdiction’s financial compensation scheme, which may have different limits and triggers than the UK’s FSCS or the robust Lloyd’s Central Fund. This structural difference is critical in a true worst-case scenario. A detailed comparison, based on a recent analysis of Lloyd’s security, highlights these architectural differences:

This does not mean one is inherently ‘better’ for all situations. A highly-rated Gibraltar insurer might offer more competitive terms on certain risks. However, from a pure risk architecture perspective, the Lloyd’s model offers a unique, collectivised security structure that is fundamentally different from a standalone carrier. The choice depends on your organisation’s appetite for counterparty risk.

How to Build a Modular Insurance Programme That Scales with Your Business?

The ultimate goal of a sophisticated risk manager is to move away from a static, reactive insurance programme towards a dynamic, modular risk architecture that can scale with the business. A modular programme is not a single, rigid policy but a flexible framework designed with growth in mind. It anticipates change rather than being broken by it. This requires shifting the focus at inception from simply securing a limit to building in scalability.

The foundation of a modular programme is an exceptionally broad and flexible primary wording. Using an ‘all risks’ structure with clearly defined exclusions, rather than a ‘named perils’ approach, creates a wider initial scope of cover. This means that as new, unforeseen risks emerge from business expansion, they are more likely to fall within the existing coverage grant, rather than being automatically excluded. Another key element is negotiating a framework for sub-limits and extensions. This allows the business to quickly and efficiently add specific coverages for new ventures or projects at pre-agreed terms, rather than having to go to the market for a separate, standalone policy each time.

Building this modularity requires specific negotiation at the outset. Key features to embed in your primary and low-level excess layers include:

• ‘Right to Add’ Clauses: Secure a contractual right to add new entities or increase limits mid-term, based on a pre-agreed premium formula. This prevents insurers from refusing capacity or price-gouging when you need to expand.
• Standardised Connection Points: Structure your policies with clear, standardised definitions and attachment points that can easily ‘plug into’ different types of excess layers or specialised policies as your needs evolve.
• Flexible Reporting: Establish a clear, non-punitive protocol for notifying insurers of material changes, turning it into a routine administrative task rather than a high-stakes strategic dilemma.

This proactive design work transforms your insurance tower from a rigid structure into an adaptable platform. It’s the difference between a brick wall and a sophisticated, scalable system. This is particularly relevant given that, according to WTW client data, the average lead umbrella limit purchased by Q1 2024 was £10.6 million, showing that building substantial towers is a common, critical task for which modular design is essential.

By adopting an architect’s mindset, you can engineer a coverage tower that is not only high but also resilient, adaptable, and structurally sound. The next logical step is to apply this framework to your own programme through a detailed audit with a specialist broker.