If you are dealing with a failed or defective deck, roof terrace or balcony decking installation and need an independent, evidence-led technical opinion, I can help.
I undertake measured site inspections to identify defects, establish their likely causes, assess the extent of the problem and determine whether repair, partial replacement or complete replacement is reasonably required.
I accept instructions from solicitors, homeowners, contractors and insurers and provide Independent Expert Opinions, technical assessments and, where formally instructed, CPR Part 35 expert reports.
Where appropriate, I can also advise on the remedial works required and provide a reasonable assessment of the likely cost of putting defective work right.
What I Investigate
My specialist areas include:
- Timber, composite and alternative decking systems
- Defective workmanship and installation
- Material and product failure
- Decking subframes, joists, beams and support arrangements
- Fixings and fastening systems
- Board spacing, movement and expansion
- Ventilation and moisture management
- Timber durability and treatment
- Falls, drainage and surface-water management
- Steps, thresholds, edging and restraints
- Balustrades and associated decking details
- Roof terraces and balcony decking
- Manufacturer installation requirements
- Relevant standards, technical guidance and accepted industry practice
Where a matter involves structural engineering or another specialist discipline beyond my expertise, I will identify this and recommend appropriate specialist input where necessary.
Expert Witness Services
Depending upon the nature and stage of the dispute, I can provide:
- Independent Expert Opinions
- Preliminary and pre-action technical assessments
- Site inspections and defect investigations
- CPR Part 35 expert reports, where formally instructed
- Single Joint Expert appointments
- Supplementary expert reports
- Scott Schedule input
- Experts’ meetings and Joint Statements
- Repair-versus-replacement assessments
- Remedial scope recommendations
- Outline remedial specifications
- Reasonable remedial cost assessments
What an Investigation May Address
Cause
Whether the problem arises from workmanship, design, specification, materials, maintenance, misuse or a combination of contributing factors.
Extent
Which elements of the installation are affected and whether the defects appear isolated or systemic.
Safety
Whether any immediate hazards are apparent and whether interim precautions may be appropriate pending remedial work.
Remedial Works
Whether defects can reasonably be repaired or whether partial or complete replacement is required, together with an appropriate outline remedial methodology.
Quantum
Where instructed, a reasonable assessment of the likely cost of appropriate remedial works, taking account of labour, materials, access, waste removal, making good and other relevant project costs.
Evidence
Measured site observations supported by a photographic record identifying and illustrating the defects found.
Independent Expert Evidence
An expert witness is not an advocate for the person instructing or paying them.
My role is to provide an independent, objective and evidence-based professional opinion within my area of expertise.
Where CPR Part 35 applies, my overriding duty is to assist the court on matters within my expertise. That duty takes precedence over any obligation to the party instructing or paying me.
Professional Standing
- Holder of the RICS Expert Witness Certificate
- Fellow – Professional Garden Consultants Association (FPGCA)
- Accredited Member – Association of Professional Landscapers (MAPL)
- Member – Institution of Engineering and Technology (MIET)
- Graduate – City & Guilds Institute (GCGI)
About Karl Harrison
Karl Harrison is a professional landscape consultant and independent expert witness with more than 20 years’ experience in landscape construction and specialist decking systems.
Working professionally within the landscape industry since 2003, Karl has extensive practical experience in the design, specification, construction and investigation of timber, composite and alternative decking installations.
He is the founder of The Decking Network and has developed a particular specialism in diagnosing decking failures, defective construction, inappropriate materials and installation methods, substructure problems, moisture management, movement and remedial construction.
Karl has also given expert evidence in the Royal Courts of Justice, where his opinions and methodology have been tested under cross-examination by barristers.
His wider professional experience in landscape construction also enables him to consider associated external works where these form part of a decking dispute.
Areas Covered
Karl accepts instructions throughout the UK by arrangement, with regular coverage across Buckinghamshire, Hertfordshire, London, Berkshire and Oxfordshire.
Contact Karl Harrison
Professional Landscape Consultant & Independent Expert Witness
Telephone / WhatsApp: 07581 193034
Email: karl@landscapingexpert.co.uk
landscapingexpert.co.uk
