Structural Waterproofing Design

BS 8102:2022
Compliant Design

CSSW Accredited · Co-author of the standard · Expert Witness

Independent Waterproofing Consultants

Major developers appoint CLW to own the waterproofing risk on their basements.

Q: How is CLW different from a manufacturer or contractor?

CLW holds no product affiliations and does not work for waterproofing contractors. This independence means CLW can challenge contractor quotes and write performance specifications that open competitive tender rather than locking the project into a single supplier.

Q: What does a typical engagement involve?

Three stages. Design (RIBA 2-4): waterproofing strategy, grade selection per zone, and risk assessment. Specification: a performance specification that enables open tender. Construction monitoring: client-side through the build, challenging departures from design intent.

Q: What does the Waterproofing Wisdom Agent do?

The Waterproofing Wisdom Agent is CLW's specialist AI for waterproofing, grounded in BS 8102:2022. Architects and project managers use it to determine BS 8102 grade, compare fee proposals and contractor tenders, generate hydrogeology risk assessments, and read general arrangement drawings. Access is granted via a short intake form.

Our unique approach delivers robust design, best value procurement and contractor accountability.

Our process

CSSW Accredited
25+ Years Experience
BS 8102:2022 Co-author

Recommended by

What we do

We own the waterproofing risk.

All too often waterproofing design falls through a scope gap, is badly procured and ultimately fails. Resulting in tenant disruption and remediation. CLW closes the gap.

Structural Waterproofing Design

'Goldilocks' design — never over-specified, never under-engineered. Precisely the waterproofing your scheme needs, set out as a clear performance specification.

BS 8102:2022 · CSSW + WDS

Best-Value Procurement

Outstanding performance specifications open the tender to competent specialist contractors — avoiding single-supplier lock-in and driving genuine competition.

Open tender · Independence preserved

Contractor Accountability

Client-side throughout construction. Inspections at critical stages. Authority to challenge when work departs from design intent.

Site inspection · Submission review

Selected projects

Commercial developments across London.

CLW are trusted by leading commercial developers and project managers to take responsibility for basement waterproofing and ensure the delivery of dry basements.

Office · Southwark

220 Blackfriars Road

Client: JTRE London · Architect: EPR Architects

Office · EC2

75 London Wall

PM: Opera PM · Client: Castleforge Partners · Architect: ORMS

Civic · Fleet Street

Salisbury Square

PM: Avison Young · Client: City of London Corporation

Mixed Use · Soho

Holden House

Client: Derwent London · Architect: DSDHA

Office · Mayfair

33-35 Piccadilly

Client: Kier · Architect: DSDHA

Office · St James

10 Piccadilly

PM: Dendy Byrne · Client: Crown Estate

View all projects →

Have a basement question that can't wait for a consultant's diary?

Put the Waterproofing Wisdom Agent on it — CLW's specialist AI, trained personally by Ben Hickman (contributor to BS 8102:2022) and free to use on your own scheme. Architects and project managers use it to:

Determine BS 8102 grade and waterproofing type for your scheme
Review and benchmark a fee proposal or contractor quote
Generate a waterproofing risk assessment — upload your ground investigation report and flood risk assessment
Get a high-level sense-check of an existing waterproofing design

A specialist tool, not a generic chatbot. It reasons in BS 8102:2022, because that's what it was built from.

Request access to the agent

We keep the agent for working design and development professionals, so we review every application. Three fields, one minute — most applicants are approved within one working day.

What clients say

“CLW have done a good job on the BM project and have provided sound advice on fairly complicated waterproofing issues and have provided responses quickly and succinctly. The BM is very appreciative of CLW's input on the project and it is invaluable. At Civic we have enjoyed working with you.”

James Bloomfield · Associate · Civic British Museum

“I've worked with CLW on several projects now. They have shown outstanding value in picking up on issues early, guiding the design team and ensuring work on site complies with best practice. Working with CLW has given me confidence in our development and the basement waterproofing. I will absolutely be working with them again on the next project.”

John Linklater · Project Director · Urbanest 2 Trafalgar Way

“I know the CMT role is not a competition between disciplines, but I have felt that CLW as its own discipline has really excelled and ensured that the requirements and best interests of the Employer have continuously been upheld by Ben and his team.”

Kiran Ragupathy · Associate · AECOM Salisbury Square Development

“I've worked closely with CLW on the Salisbury Square Development scheme, and they have shown outstanding value in picking up on issues early, guiding the design team and ensuring work on site complies with best practice. Working with CLW has given me confidence in our development and the basement waterproofing.”

Jianxi Cheng · Director · Avison Young Salisbury Square

“Johnny has put the interest of the client first. In a complicated civil engineering project he has ensured that all due considerations have been made. He has managed the contractor well and ensured his design is well communicated. Should a project require it I will in future be reaching out to CLW.”

Laurance Townsend · Senior Project Manager · Oxford Science Park

“Derisking basement reuse required specialist waterproofing early in our design. CLW were a great addition to the design team and immediately showed their worth. The team have continued to show great value through collaboration with the main contractor during the PCSA; ultimately bringing clarity to the risk and enabling robust mitigation.”

Will Jarrett-Kerr · Project Director · Opera 75 London Wall

“I worked with CLW on the 220 Blackfriars Road project and found their team to be very competent and professional. Their technical expertise on waterproofing design was valuable and allowed us to overcome some complex challenges.”

Miguel Bronze · Project Director · EPR Architects 220 Blackfriars Road

CLW credentials

The authority on basement waterproofing design.

CLW's team includes three registered Waterproofing Design Specialists and an ARB-registered Architect. Ben Hickman contributed to BS 8102:2022.

White papers & resources →

Registered WDS Specialists

25+

Years specialist experience

£10m

Professional indemnity

BS
8102

2022 contributor

65,000+ hrs

Hours of specialist waterproofing consultancy delivered by CLW since 2016

FAQ

Common questions

Practical answers on engagement, scope, BS 8102 and the Waterproofing Wisdom Agent.

What is BS 8102:2022 and why does it matter?

BS 8102:2022 is the British Standard for protection of below-ground structures against water ingress. It is the primary reference standard for basement waterproofing design in the UK. Ben Hickman contributed to the 2022 revision. We design to its requirements on every project, which means our clients can be confident their buildings comply with current best practice. See our full BS 8102 grade reference →

When should CLW be appointed on a project?

As early as RIBA Stage 2. The earlier the appointment, the more options remain on the table. By Stage 4, key Type A/B/C decisions and structural interfaces are often locked in — sometimes against waterproofing best practice. We can still help later in the programme, but the framing shifts from prevention to triage. How our process works stage by stage → · When to appoint a waterproofing consultant →

How is CLW different from a manufacturer or contractor?

We hold no product affiliations and we do not work for waterproofing contractors. Our independence is the moat: it means we tell you when a contractor quote is wrong, and we can write performance specifications that open competitive tender rather than locking the project into a single supplier. Why independence matters → · White paper: contractor risk →

What does a typical engagement involve?

Three stages. Design (RIBA 2–4): we develop the waterproofing strategy, grade selection per zone, and risk assessment. Specification: we write a performance specification that enables open tender. Construction monitoring: we remain appointed client-side through the build to challenge departures from design intent. Structural waterproofing design → · Construction monitoring → · Full process overview →

What does the Waterproofing Wisdom Agent do?

The Waterproofing Wisdom Agent is our specialist AI for waterproofing, built on two decades of CLW's basement waterproofing experience and grounded in BS 8102:2022. Architects and project managers use it to determine BS 8102 grade, compare fee proposals, generate risk assessments, and read GAs and pre-construction packs. Most applicants are approved within one working day — request access via the form above. Learn more about the Wisdom Agent →

CPD for architects, engineers, project managers

Book a 45-minute CPD on basement waterproofing risk.

Run for design teams in-house. Real failure case studies, not slides about products. BS 8102:2022 in practice.

Request a CPD Or talk to us