External Weatherproofing
external weatherproofing
What is external weatherproofing?
Occasionally, moisture can seep through the walls of the building. It’s the result of wind-driven rain rather than dampness below ground. Properties that are particularly exposed, or contain porous building materials often suffer from wet internal walls.
The problems caused by moisture through the walls include:
- Damage to internal plaster
- Water stains and tarnished decorations
- Fungal decay in timbers
Our trained surveyors will identify the cause of the problem and find a solution that stops damp returning.
How we can help
We’ll give you the external weatherproofing you need to make sure your walls are robust for the long-term. Our surveyors will advise you on the most appropriate solution for your property, which may include:
- Applying a breathable, acrylic-based surface coating to the exterior of the building
- Specialist replastering to rectify damage to internal surfaces
Quality Guaranteed
Trusted, qualified experts
With over 30 years’ experience, it’s unlikely that we meet a problem we haven’t fixed before. We’ll give you an accurate estimate of the work involved in your external weatherproofing and how much it will cost.
Verified for quality
All of our surveyors are CSSW certified, which is the gold-standard qualification for waterproofing. We’re also a long-standing member of the British Structural Waterproofing Association, and we’re approved contractors for all Delta waterproofing systems. You can rely on the quality of our work, which is validated by the key players in our industry.
Trusted Across Bath, Bristol & the South West
Cannon Clarke delivers domestic and commercial structural waterproofing across:
- Bath — heritage properties, basement conversions, retaining walls
- Bristol — modern developments, commercial units, residential refurbishments
- Somerset & Wiltshire — rural properties, cellars, below‑ground extensions
Trusted by:
- Surveyors
- Insurers
- Property managers
- Homeowners across the South West
Our reputation is built on technical accuracy, reliability and long‑term results.
Case Study Snapshots
Bath — Basement Conversion
Installed a full cavity drainage system with sump and pump, resolving long‑term damp issues and enabling a habitable living space.
Bristol — Commercial Unit
Applied cementitious waterproofing to retaining walls experiencing hydrostatic pressure, preventing water ingress during peak rainfall.
Somerset — Heritage Property
Designed a non‑intrusive waterproofing solution compatible with historic masonry and conservation requirements.
Compliance & Standards
Our waterproofing systems meet:
- BS 8102:2022 — Code of practice for protection of below‑ground structures where applicable
- Manufacturer installation standards
- Insurance‑backed guarantee requirements
All work is carried out by our employed trained specialists with extensive experience in below‑ground protection.
FAQs
What causes basement leaks?
Basement leaks are typically caused by hydrostatic pressure, poor drainage, failed membranes or structural cracks.
Do you follow BS 8102?
Yes. Where Applicable all waterproofing systems are designed and installed in accordance with BS 8102:2022.
Can waterproofing be added to existing basements?
Absolutely. We regularly retrofit waterproofing systems to older properties and heritage buildings.
How long does installation take?
Most projects take between 5–10 days depending on size and complexity. (larger projects will take longer.
Do you offer guarantees?
Yes. We provide manufacturer-backed and insurance-backed guarantees where applicable.
More information?
For reliable structural waterproofing, call Cannon Clarke or book a professional survey. We’ll assess your property, explain your options and provide a clear, compliant plan.
Our Process
Survey
We start by conducting a thorough survey of the space you want inspected. There's usually a fee for our initial consultation.
01
Scoping discussion
We collaborate with you to marry your objectives with our findings from the survey. We’ll discuss how you want to use the space when it’s finished and the best way of achieving your vision.
02
Design
Once we have the physical specifications, and your input on your requirements, we’ll design a system that works for you.
03
Approval
We’ll send you a specification, together with a report which explains the technical aspects. We’re happy to chat through this with you and make any changes you’ve identified.
04
Work begins
With an approved plan in place, we’ll get to work on the date we’ve agreed between us.
05