Independence and competence
Every waterproofing consultant will tell you they are independent. Most of them are not.
Independence is a deliberate commercial choice that requires giving things up. This guide sets out what it means, why it matters on a major project, and the six questions you can use to verify it before you sign anything.
Definition
What independence means in structural waterproofing
An independent structural waterproofing consultant has no financial relationship with any part of the waterproofing supply chain. That means no product agency agreements. No contractor referral arrangements. No incentive - explicit or implicit - to specify one product over another, or to recommend a particular contractor.
This matters because the structural waterproofing market is not structured for independence. The dominant commercial model is supply chain-led. Manufacturers offer design services as a route to product specification. Installer networks maintain relationships with consultants who steer work their way. Some firms that describe themselves as consultancies are, in practice, arms of a contractor group or a product supplier.
Independence eliminates the conflict at source. An independent consultant's fee is paid by the client. Their interest is in the outcome of the project - not in selling materials, protecting an installer relationship, or preserving a product agency agreement that generates income alongside the fee.
Why it matters
Three areas where a conflict of interest becomes critical.
Specification
An independent consultant writes an open performance specification: what the waterproofing must achieve, not which product must be used. This keeps the tender competitive, gives the contractor freedom to price efficiently, and gives the client the best available value across the compliant market. A supply chain-linked consultant will specify by brand. The tender field narrows. Competition disappears.
Risk area | Procurement
Procurement advice
Genuine independence means advising on procurement structure without a stake in the outcome - including advising when a contractor-designed-and-installed solution is appropriate, and when it is not. A consultant with installer relationships has no incentive to recommend competitive procurement.
Risk area | Procurement structure
Construction monitoring
A client-side monitoring role requires the consultant to hold the contractor accountable to the specification. A consultant with a relationship to that contractor - or to the product supplier the contractor has selected - cannot fulfil this role impartially. The conflict is structural.
Risk area | CMT role
Accreditation
The technical baseline: WDS and CSSW
The relevant UK accreditation is the Waterproofing Design Specialist (WDS) designation, administered by the Property Care Association. WDS accreditation confirms technical competence in structural waterproofing design to BS 8102:2022. It does not confirm independence - but it is the technical baseline.
CLW holds the UK's highest concentration of WDS-accredited staff. All design team members hold CSSW qualification at minimum. Technical Director Ben Hickman contributed as a committee member to the 2022 revision of BS 8102 itself.
Accreditation answers the competence question. Independence answers the conflict-of-interest question. Both need to be satisfied. They are not the same thing and one does not imply the other.
Professional formation
The foundation beneath the waterproofing accreditation.
Relevant degree
Structural waterproofing sits at the intersection of structural engineering, architecture, geotechnics, and materials science. A consultant advising on a complex commercial basement is making decisions that interact with the structural design, the drainage strategy, the architectural detailing, and the ground investigation findings. That requires a degree in a relevant discipline - structural engineering, civil engineering, architecture, or building engineering - before the waterproofing-specific layer can be applied.
Qualification check | Degree discipline
Chartered body membership
Chartered membership of a professional body - RIBA, ARB, CIOB, CABE, ICE, IStructE, or RICS - means someone is held accountable by an institution with a code of conduct, CPD requirements, a disciplinary process, and a PI framework. A consultant who holds no chartered membership has no professional body holding them to account beyond their own firm.
Qualification check | Accountability
WDS or CSSW on top
WDS and CSSW confirm that the holder understands BS 8102 and can apply it. They can be obtained by experience route without a degree and without chartered membership. That is not the same as professional formation. The waterproofing accreditation should sit on top of a professional foundation - not in place of it.
Qualification check | Waterproofing specialism
Due diligence
Six questions to ask before you appoint.
A genuinely independent, properly qualified consultant will answer all six without hesitation. Evasion or qualification on any of them is a signal.
Do you hold any product agency agreements?
An independent consultant holds none. The answer should be an unqualified no. Any qualified answer - 'not formally', 'we prefer certain products', 'we work closely with a few suppliers' - means the answer is yes.
Independence check
Do you receive any payment from waterproofing contractors or installers?
This includes referral fees, retrocession arrangements, and any commercial benefit from contractor instruction. An independent consultant receives no payment from the supply chain. Any payment structure that involves the consultant benefiting when a particular contractor is appointed is a conflict of interest.
Independence check
Who underwrites your Professional Indemnity insurance?
Some PI policies in the waterproofing sector are underwritten by product manufacturers or trade bodies with commercial interests in the sector. An independent consultant holds PI insurance with an arm's-length insurer. Ask to see the policy summary and check the underwriter.
Independence check
What is the ownership structure of your firm?
Some firms that operate as consultancies are owned by, or hold financial relationships with, contractor groups or product distributors. Companies House is a public register and this is a straightforward verification. The answer should be verifiable in under five minutes.
Independence check | Companies House
Can you write an open performance specification across all compliant products and systems?
A specification that names no specific products and is compliant with BS 8102:2022 is the functional test of independence. Ask to see an example from a recent project. If they cannot produce one, they do not write them.
Competence check | BS 8102:2022
What are the qualifications of the individuals who will actually do the work?
This needs answering at two levels. Does each team member hold a relevant degree? Is each member a chartered member of a recognised professional body - RIBA, ARB, CIOB, CABE, ICE, IStructE, or RICS? Ask for individual CVs, not a summary of firm credentials. Some firms list impressive credentials at firm level that do not reflect the qualifications of the person you will actually be working with.
Competence check | Degree + charter
Waterproofing Wisdom Agent
Run the due diligence check with CLW's AI agent.
If you are currently holding fee proposals from multiple waterproofing consultants - or from specialist waterproofing contractors - CLW's Waterproofing Wisdom Agent includes a dedicated pathway that runs a systematic two-stage due diligence check across every submission.
The agent assesses each proposal against independence criteria and technical competence criteria. It identifies gaps in scope, flags signs of supply chain affiliation, and produces a written comparative report you can use to inform the appointment decision. The technical competence weighting goes beyond surface credentials to assess whether the proposal demonstrates the reasoning that genuine waterproofing expertise produces.
It was built precisely because fee comparison in waterproofing is often misleading. A cheaper consultant who holds a product agency agreement is not cheaper when you factor in the over-specification that follows. The agent normalises proposals to a like-for-like basis so the comparison is honest. If what you are holding is contractor quotes or tender returns rather than consultant fee proposals, start with how to compare waterproofing quotes and tenders.
Compare your fee proposals with the Waterproofing Wisdom Agent →Common misconceptions
Things that sound reasonable but are not.
The main contractor carries the risk anyway.
The main contractor carries contractual risk under the defect liability period. Latent defects in waterproofing typically do not manifest within the DLP. By the time the defect becomes apparent, the DLP has expired, the contractor has moved on, and the remedial cost lands with the building owner. Independent advice structured before the build is the only reliable mitigation.
Supplier warranties cover it.
Supplier warranties are conditional on the product being installed in accordance with the manufacturer's specification. They are also enforced by the supplier - who has a commercial interest in limiting liability. An independent consultant's specification creates contractual obligations that do not depend on a supplier's warranty.
Any WDS-accredited consultant is independent.
WDS accreditation confirms technical competence in waterproofing design. It does not confirm independence. A WDS-accredited consultant can hold product agency agreements. The two criteria are not the same and both need to be satisfied independently.
Years of experience is a reliable proxy for qualifications.
Experience matters. But experience without professional formation produces consultants who have learned inside one firm's way of thinking, without the peer review, examination, and accountability structures that professional body membership requires. An experienced consultant who holds no relevant degree and no chartered membership has never been assessed by anyone outside their own organisation.
Questions and answers
Independence and competence: what you need to know.
Straight answers on what independence means, how to verify it, and what qualifications to look for.
What does an independent structural waterproofing consultant do?
How do I know if a waterproofing consultant is genuinely independent?
What is BS 8102:2022 and why does it matter for independence?
What is the WDS designation and does it confirm independence?
What qualifications should a structural waterproofing consultant hold?
Can I use an AI tool to compare fee proposals from waterproofing consultants?
Does CLW hold any product agency agreements?
CLW
Independent expertise on your side.
Independence in structural waterproofing is verifiable. It requires no product agency agreements, no contractor relationships, and PI insurance held at arm's length from the supply chain. It enables open performance specifications, competitive procurement, and impartial construction monitoring.
Professional competence is separately verifiable. It requires relevant degrees, active membership of recognised chartered bodies, and WDS or CSSW accreditation on top of that foundation.
CLW meets all six of the verification questions above and is able to demonstrate that on request. If you are comparing proposals from multiple consultants now, the Waterproofing Wisdom Agent can run the due diligence check for you.
Disclosure: Ben Hickman is co-founder of Vector Leak Consultants, a sensor-based leak detection and prevention company. CLW and Vector are operationally and commercially separate, and CLW receives no referral fees from Vector. Where CLW’s waterproofing advice intersects with sensor specification — for example, post-construction moisture monitoring — clients should be aware of this relationship and satisfy themselves independently on sensor procurement.