CNJ Construction Consultants

Accurate Costing That Protects Your Margin

Independent construction consultancy for contractors, combining quantity surveying, cost planning and tender support with live commercial control to help protect your margin.

Trusted by contractors, developers, and industry professionals

Who we are

Commercial Cost Support for Contractors

CNJ provides independent construction consultancy for contractors across Surrey, London and the South East. Our quantity surveying and commercial support help you understand project costs, prepare competitive tenders and maintain control from pre-contract planning through to delivery.

Before work begins, we review drawings, specifications and scope to prepare cost estimates, detailed cost reports and bills of quantities. Our pre-contract cost planning and tender support make assumptions, exclusions and pricing risks clearer, so you can submit a considered price rather than rely on incomplete information.

Once a project is underway, our post-contract commercial support covers cost management, interim valuations, variations and final accounts. We help assess changes, track expenditure and keep payment information organised, giving you a clearer view of cash flow and your commercial position.

We understand the pressures of competitive tendering, fixed-price work and changing scope. Our role is to help you spot exposure early, make informed decisions and protect margin with practical cost advice. Learn more about CNJ’s contractor support, or explore our homeowner services when your client needs independent advice.

What we offer

Services for Contractors

Cost Estimates

Drawings-based cost estimates and cost planning using current market rates. Understand scope, allowances and exclusions before committing to a tender price, so you can assess risk and protect your margin.

Detailed Cost Reports

Itemised cost reports and quantity surveying support that clarify labour, materials and project allowances. Use a transparent breakdown to review pricing, compare options and discuss cost decisions with clients.

Tender Package

Tender pricing, bills of quantities and commercial review to support a clear, considered submission. Identify scope gaps, assumptions and exclusions before award, reducing ambiguity and avoidable post-contract exposure.

Reports in 2025

Contractors worked with

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Value of projects for 2025

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Company growth between 2024-2025

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Our Proven 3-Step Approach Gives Contractors Cost Certainty

Building work does not need commercial uncertainty. CNJ’s contractor-focused approach provides clear pricing, structured tender support, and ongoing cost insight, helping you commit to figures with confidence and protect margin from tender stage through delivery.

Step 1: Share Your Scope

Share your drawings, specifications, and tender requirements. We review scope, assumptions, and constraints to understand feasibility, risk, and pricing context.

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Step 2: Receive Clear Pricing

Receive cost estimates, detailed reports and bills of quantities aligned with scope, programme and current market rates. Review assumptions and exclusions with our team before deciding how to price your tender.

Step 3: Deliver With Commercial Control

Keep project costs, payments and scope changes visible during delivery. Our post-contract support covers cost management, variations, interim valuations and final accounts, helping you manage cash flow and protect margin.

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Ready to Discuss Your Project?

01483 339 733

Speak directly with our team or share your project details online. We will quickly assess where we can add commercial value.

Testimonials

Client Feedback & Reviews

“Conceptual Design Associates Ltd have been working with CNJ construction consultants for a number of years now, we have found Joshua Randall and the team at CNJ to be highly professional and knowledgeable in a volatile and uncertain construction industry. During and after Covid material and labour costs seem to increase at an unprecedented rate and we have relied on CNJ to give us and our clients cost certainty for their construction projects. Their advice and value engineering when required has given our clients comfort that their project will come in on budget. Our projects range from large domestic additions, to one off exclusive dwellings to multi-unit residential and mixed use schemes and we use CNJ on all of these types of schemes.”

“GLR has been using CNJ’s Quantity surveying services for 3 years. We have worked collaboratively pricing and winning projects, and have used their Cost Management service to monitor valuations, variations and final accounts on the majority of our projects. This provides financial security throughout the lifecycle of the project.”

“We have been using CNJ Construction Consultants for the past six years, and they have consistently delivered exceptional service. Their professionalism, reliability, and attention to detail set them apart from anyone else we’ve worked with. Their costs are reasonable, especially considering the quality of service they provide. One of the biggest advantages of working with CNJ is their face-to-face approach, which has proven incredibly valuable for our clients compared to online-only alternatives. This personal touch builds trust, improves communication, and ensures projects run smoothly from start to finish. We fully recommend CNJ Construction Consultants to anyone looking for a trustworthy, knowledgeable, and highly professional team. We will certainly continue to work with them for many years to come.”

“CNJ Consultants have helped me grow my business substantially. I have been working with Joshua, the Managing Director, for over 5 years and I can sincerely say that he made my life easier. CNJ are able to price jobs for me and provide valuations incredibly efficiently and are always on time. I can honestly say that CNJ are the 'go to' Consultancy services company who you can truly rely on at all times.”

"CNJ have been a great support to our business, particularly with estimates. Their work is detailed, well-structured, and easy to follow, and they’re always happy to talk through assumptions, exclusions, and any areas that need refining as a project develops. We’d happily recommend them to any contractor looking for a reliable estimating/QS partner"

Construction Consultancy for Contractors: FAQs

From tender pricing to live project cost control, contractors need clear information at every stage. These answers explain how CNJ’s quantity surveying and commercial support can help you manage costs, changes and payments. Explore our construction consultancy services or discuss your project with the team.

What does a construction consultant do for contractors?

A construction consultant helps contractors make informed decisions about pricing, scope and project costs. CNJ combines quantity surveying, cost planning and tender support with live commercial advice, helping you identify risks before award and manage costs, changes and payments during delivery.

Can CNJ help with tender pricing?

Yes. CNJ can review drawings, specifications and tender requirements, prepare cost estimates and bills of quantities, and clarify assumptions or exclusions. Our pre-contract support helps you build a considered tender price and understand the commercial exposure before submitting it.

Can CNJ support live project cost control?

Yes. Our post-contract cost management supports contractors once work is underway. We help monitor expenditure, prepare valuations, reconcile costs and organise payment information so you can understand cash flow and act on developing cost pressures.

Can CNJ help with variations and valuations?

Yes. CNJ helps assess and price scope changes, prepare supporting cost information and manage interim valuations. Keeping variations and payment records clear helps reduce the risk of unpriced additional work and gives you a stronger basis for commercial discussions throughout the project.

How can contractors protect margin during a project?

Margin protection starts with a clear scope, realistic pricing and visible assumptions. During delivery, track expenditure, record instructions and changes, price variations promptly and keep valuations up to date. CNJ’s commercial support helps you identify exposure early and make informed decisions; it cannot remove every project risk or guarantee a profit.

Can CNJ help with final accounts?

Yes. CNJ’s post-contract support includes reconciling project costs and final accounts. Bringing valuations, agreed variations and payment records together helps contractors understand the outstanding commercial position and prepare for final account discussions.

Why CNJ

Why Contractors Choose CNJ

Contractors need practical commercial advice they can use before committing to a price and throughout delivery. CNJ supports you with:

Independent contractor-side advice: clear cost information to support your own commercial decisions.
Detailed pricing and scope review: cost estimates, reports and tender support that make assumptions and exclusions visible.
Continuity from tender to final account: quantity surveying support for valuations, variations and ongoing cost management.
A focus on margin and cash flow: timely cost insight to help you identify exposure and manage changes.

Meet CNJ and explore our contractor experience, or discuss the support your project needs.