Specification Writing Services

What is a Specification?

A specification often serves as the backbone of your procurement or tendering process! It provides a detailed statement of requirements that suppliers must meet. This document will clarify exactly what suppliers need to deliver, it will establish measurable standards, and becomes a legally binding document to protect your interests throughout the entire project lifecycle. This is what can be achieved with a tailored, relevant, considered and well-written specification! 

The Cost of Poor Specifications

 When specifications lack clarity or precision, suppliers can legally deliver substandard work whilst technically meeting the minimal contractual requirements. Contract management becomes virtually impossible without clear performance measures, leaving you with limited recourse when problems arise.

Projects frequently experience cost overruns, quality deficiencies and extended timelines as disputes emerge from ambiguous requirements. The relationship between client and supplier often deteriorates, and legal challenges may follow - all stemming from documentation that failed to properly articulate project requirements. Get the foundations in place - and this requires a good spec! 

Thornton & Lowe's Specification Writing Expertise

At Thornton & Lowe, we write specifications that actually work. No fluff, no jargon – just clear, practical documents that protect your interests throughout the procurement process.

Our approach is straightforward but effective. We understand what you need, then create specifications that tell suppliers exactly what to deliver. By working with buyers and suppliers across thousands of tenders we understand what is required to produce a really effective specification, and this include engaging the right subject matter expertise. We focus on three things that matter most:

First, we ensure compliance while promoting fair competition. We never bias specifications toward particular suppliers or unnecessarily reference specific brands. This creates a level playing field that attracts quality bids while clearly communicating your requirements.

Second, we establish measurable requirements with enforceable criteria. We define clear success parameters using specific metrics rather than vague descriptions. This gives both you and suppliers certainty, allowing for accurate pricing and straightforward performance tracking.

Third, we build contract management tools directly into your specifications. By including robust performance indicators from the start, we provide the framework you need to manage the contract effectively after award. This ensures suppliers deliver what was promised rather than what they thought you wanted.

Our specifications our practical tools that reduce risks, improve value, and deliver better procurement outcomes – without the unnecessary complexity that often plagues technical documentation.

Elements of Effective Specification Writing

Creating really effective specifications requires a methodical approach that balances technical detail with practical outcomes. We break down objectives into logical components, which are based around what is important for the contract - from requirements and goals, to risks and compliance. 

Communication clarity stands at the heart of good specification writing. We write in clear, direct language without unnecessary technical jargon. This ensures all parties interpret the specification in exactly the same way, eliminating costly misunderstandings that can plague projects from inception through to completion.

Perhaps most importantly, we focus on outcomes - what will it actually produce? By specifying what outcomes you need - not how contractors should achieve them - we place responsibility appropriately whilst encouraging innovation in delivery methods. This approach prevents suppliers from claiming that by following prescribed methods, they've met their obligations despite failing to achieve the desired results. There are other types of specifications which can also help with - detailed below. 

Our Specification Development Process

When developing specifications that truly serve your interests - you should begin with a: 

• Thorough requirements gathering involves working closely with stakeholders to understand precise needs and objectives - this may include surveying customers, but certainly working with technical team members
• Research and planning phase identifies all relevant technical standards and regulatory requirements, ensuring compliance from the outset
• Review and refinement process ensures all requirements are accurately captured and presented in a logical, accessible format. This is then ready for final delivery. A specification document ready for immediate use in procurement, saving you time and reducing risk.

Types of Specifications: Making the Right Choice

Understanding the different types of specifications and when to use them is essential for effective procurement. Each type has distinct advantages, limitations, and implications for both buyers and suppliers.

Prescriptive Specifications

Prescriptive specifications (also called conformance or technical specifications) provide detailed instructions about exactly what is required, including specific materials, dimensions, manufacturing processes, and workmanship standards. Think of these as detailed recipes that suppliers must follow precisely.

Advantages:

• Give buyers greater control over the final product or service
• Provide clarity and certainty about what will be delivered
• Make it easier to compare supplier bids on a like-for-like basis
• Better suited for complex, safety-critical, or specialised requirements

Disadvantages:

• Place most risk with the buyer - if the specification is wrong, the outcome will be wrong
• Limit supplier innovation and potentially more cost-effective solutions
• Require more technical knowledge from the buyer
• May lead to higher costs as suppliers have less flexibility to optimise

Prescriptive specifications are generally more challenging to write well as they require comprehensive technical knowledge and attention to detail. They're most appropriate when you know exactly what you want and how it should be produced.

Performance Specifications

Performance specifications focus on what the product or service needs to achieve rather than how it should be made. These outline specific requirements in terms of functionality, outcomes, and measurable performance standards.

Advantages:

• Encourage supplier innovation and potentially better value solutions
• Place more risk with the supplier for achieving the required outcome
• Allow suppliers to use their expertise to meet requirements efficiently
• Often lead to more competitive pricing as suppliers can optimise their solutions

Disadvantages:

• May result in varied solutions that are harder to compare during procurement
• Give less control over the specific approach or materials used
• Require clear, measurable performance criteria to be effective
• May lead to interpretation differences if not carefully drafted

Performance specifications are often easier to write as they focus on outcomes rather than technical details. However, defining appropriate performance metrics requires careful consideration to ensure they're measurable and relevant.

Output Specifications

Output specifications define the specific outputs required from a product or service, focusing on what needs to be delivered rather than how. These are commonly used in service contracts and public-private partnerships.

Advantages:

• Focus on definable, measurable outputs
• Provide clear criteria for contract management
• Allow flexibility in delivery methods
• Work well for service-based contracts

Disadvantages:

• May not capture all aspects of quality or user experience
• Can be difficult to define appropriate metrics
• Risk of focusing on outputs at the expense of outcomes

Outcome Specifications

Outcome specifications describe the broader outcomes or benefits that should result from the product or service. These focus on the ultimate purpose or end result.

Advantages:

• Align procurement with strategic objectives
• Encourage solutions that address the fundamental need
• Allow maximum supplier innovation
• Focus on value rather than just outputs

Disadvantages:

• Outcomes can be difficult to measure directly
• May be too abstract for some suppliers to interpret
• Require sophisticated contract management

Most projects benefit from combining elements of different specification types. For example, using performance specifications for areas where supplier innovation is valuable, while using prescriptive specifications for critical interfaces or safety elements. The right balance depends on your specific requirements, risk appetite, and market capabilities. 

You may also be interested in a specific example of writing a grounds maintenance specification. 

Practical Guidance for Better Specifications

Below we have some highly practical tips and guidance on writing specifications, including how to work from your existing specification, if appropriate. 

Developing Tailored, Effective Specifications

One of the biggest frustrations for suppliers is receiving specifications they know won't work in practice. Generic "off-the-shelf" specifications that haven't been updated or tailored to specific requirements waste everyone's time and rarely deliver value. Effective specification writing requires a thoughtful approach that combines industry standards with project-specific needs.

It's exactly the same if you apply for a job - the specification looks great. 2 weeks in and... "oh dear" - why didn't they just explain practically what they actually needed?

Preliminary market engagement (PME) can play a key role in developing truly effective specifications. By consulting with potential suppliers before finalising requirements, you can gain valuable and practical guidance, often including real innovation. This engagement helps ensure your specification reflects the current state of the market rather than outdated assumptions.

When revising existing specifications, don't simply replicate previous documents. Instead, critically evaluate how the current contract is performing. What issues have arisen? Which aspects work well? What improvements would deliver better value? This reflective approach ensures your specification evolves based on real-world experience rather than theoretical ideals.

Specifications must also of course incorporate the most up to date legislation and government guidance. Regulatory requirements change regularly, and specifications that fail to reflect current standards create compliance risks. A thorough review of relevant legislation, industry standards and government policies should be standard practice before finalising any specification.

Key Elements for Tailored Specifications

Managing Responsibility

Responsibility must be clearly defined to prevent disputes and ensure all parties understand their obligations. Poorly defined responsibilities lead to finger-pointing, delays and additional costs that could have been easily avoided with proper documentation.

The foundation of clear responsibility lies in collaborative planning. Before finalising specifications, bring together key stakeholders to walk through responsibilities for each element of the project. These discussions often reveal assumptions and misunderstandings that can be addressed before they become costly problems. Document these discussions in a formal responsibility matrix that clearly outlines which party is responsible for each aspect of delivery.

Document boundaries with particular care, especially where multiple parties interface on a system. These boundaries represent the greatest risk areas for responsibility gaps or overlaps. Specify exactly where one party's responsibility ends and another's begins, including physical locations, data handoffs, or procedural transitions.

Key Responsibility Documentation Elements

For complex projects, consider including a section in your specification that explicitly addresses responsibility transitions during the project lifecycle. As projects progress from concept to implementation, responsibilities often shift between parties. Documenting these transitions, including timing, handover requirements and ongoing obligations, prevents confusion and ensures continuity.

The verification process serves as the ultimate test of responsibility. For each major deliverable, specify not only what must be delivered but how compliance will be measured, who will conduct verification, what documentation is required as evidence, and the consequences of non-compliance. This verification framework transforms responsibilities from abstract concepts into concrete deliverables with clear acceptance criteria.

By establishing these foundations of tailored requirements and clear responsibility, your specifications will serve their purpose effectively - providing the clarity that prevents disputes, controls costs, and ensures you get exactly what you need from suppliers.

Why Choose Thornton & Lowe?

Our specification writing services are practical, bespoke and based on working on thousands of tenders working with both buyers and suppliers. We understand the important connection between a well written specifications and successful project delivery! It's one of your key tools for effective contract management. 

As part of our procurement consultancy we often work with public and third sector buyers to improve their specifications and wider procurement documentation. See a case study here - of our work with South Lakes Housing, for example. 

Contact Thornton & Lowe today to transform your requirements into precise, effective specifications that protect your interests and ensure suppliers deliver exactly what you need.

"It's been a pleasure working with Steve and the wider team at T&L. Highly practical approach - commercially focused and a great example of procurement consultancy and grounds maintenance expertise. We look forward to working with them" Paul Smith - Head of Assets and Building Safety - South Lakes Housing

“Steven is highly experienced and knowledgeable. Very approachable and responsive - Steven integrated well into the team. Steven provided value add and great input around the commercial and project approach.” Matthew Rains, Head of Procurement, Longhurst Group

"T&L are consummate professionals, taking time to understand business needs. Dave and his team have a pragmatic, outcomes based approach. Highly recommended!” Matthew Eddisford, Chief Executive, Care Housing