Acquisition Due Diligence
Pre-purchase waterproofing surveys.
Asset-grade independent assessment of below-ground waterproofing condition and risk. Before you sign.
What this service is
Specialist assessment, not a damp survey.
A pre-purchase waterproofing survey is CLW's independent assessment of the waterproofing condition and risk profile of an existing below-ground structure, commissioned by a prospective purchaser, investor, or developer before they acquire a property with basement or below-ground elements. The survey provides a clear-eyed assessment of the current waterproofing performance, identifies existing defects and latent risks, evaluates the as-built waterproofing strategy against current standards, and quantifies the likely cost and complexity of any remedial works required.
This is not a damp survey. It is a specialist assessment by waterproofing engineers who understand the structural, material, and hydrogeological factors that determine waterproofing performance – and who have the forensic experience to identify problems that a general building survey would miss.
When is it needed?
During due diligence. Before the purchase decision is made.
A pre-purchase waterproofing survey is needed before acquiring any commercial property that includes below-ground spaces – basements, underground car parks, service tunnels, vaults, or any structure below the external ground level. The need is amplified in situations where: the intended use of below-ground spaces will change (particularly where the new use is more moisture-sensitive than the current use); the property includes historic below-ground structures whose original waterproofing is unknown; the vendor's disclosure of waterproofing condition is limited or absent; there is visible evidence of dampness, water ingress, or previous remedial works; or the acquisition involves significant below-ground space that materially affects the property's value.
The survey should be commissioned during the due diligence phase of the acquisition, in time for the findings to inform the purchase decision and, if the acquisition proceeds, the remedial works budget and programme.
What CLW delivers
Six survey outputs.
Desktop review
A review of available information including as-built drawings, previous survey reports, maintenance records, and any available information on the original waterproofing construction.
Visual inspection
Inspection of all accessible below-ground areas, assessing: evidence of current or historic water ingress, condition of visible waterproofing elements, condition of drainage systems, evidence of previous remedial works and their effectiveness, and structural condition relevant to waterproofing performance.
Condition assessment
A clear, factual assessment of the current waterproofing performance, distinguishing between systematic issues (indicating fundamental design or construction deficiencies) and isolated defects (indicating localised problems that can be addressed discretely).
Risk assessment
Evaluation of the waterproofing risks associated with the property, including: the adequacy of the as-built waterproofing strategy against current standards (BS 8102:2022), the risk of future waterproofing failure based on observed conditions and known ground conditions, and the implications of any proposed change of use.
Options appraisal
Where remedial works are likely to be required, CLW provides an options appraisal setting out the available remedial strategies, their relative cost and effectiveness, and their implications for the property's use and programme.
Cost guidance
Outline cost guidance for remedial works, suitable for informing the acquisition decision and budget planning.
How it connects
Survey today, design tomorrow.
A pre-purchase survey frequently leads to further CLW involvement. Where the acquisition proceeds and remedial waterproofing works are required, CLW can develop the remedial strategy into a structural waterproofing design, produce a performance specification for the remedial works, advise on procurement of a specialist remedial contractor, and provide construction monitoring during the remedial installation. The survey findings also provide the baseline condition assessment that is essential if waterproofing-related issues subsequently arise in the context of dispute resolution – establishing what was known about the waterproofing condition at the time of acquisition.
Considering a Property Purchase?
Our pre-purchase waterproofing surveys identify risks before you commit. Protect your investment with independent expert assessment.
Book a Survey