A special four-part series to master garden drainage with Paul Greenyer, open to both members and non members of the SGDG.

All four parts are sold as a block:

• COST: Early-bird rate: £120, if booked by 31st December 2025
  Standard rate: £140
  Please book tickets below
• TIME: All talks will be at 10am to 12.30pm, including a 15 minute break.
• DATES: February 5th, 12th, 19th, 26th.

1) Thursday 5th February — “What Lies Beneath”
Materials, Layers & the Structural Principles Behind Effective Drainage

A technically grounded look at the essential components that make drainage systems work: geotextiles, membranes, pipework, bedding layers, chambers and sub-bases.
We’ll reference how the updated BS 7533-102 and upcoming BS 7533-103 (in draft) inform modern construction layers and material selection.

Designers will gain clarity on the unseen structures that determine performance, longevity and compliance.

2) Thursday 12th February — “Interpreting the Site”
Levels, Soil, Water Movement & Reading a Garden with Accuracy

This session focuses on how to understand a site before any design begins.
We’ll cover accurate level assessment, gradients, soil behaviour, infiltration potential and the impact of existing features on water movement.

Attendees will see how early site understanding aligns with the expectations behind the new British Standards and prevents costly errors later in the build process.

3) Thursday 19th February — “Detail Drives Performance”
Falls, Transitions, Interfaces & Technical Detailing That Prevents Failure

An in-depth exploration of the details that make drainage succeed — or fail.
We’ll look at falls, threshold interfaces, changes in surface material, drainage pathways, bedding compatibility and moisture management.

These principles are linked directly to the requirements and intent of BS 7533-102/103, giving designers the confidence to specify with accuracy and avoid common installation pitfalls.

4) Thursday 26th February — “From Design to Reality”
Case Studies, Common Failures & How the Standards Would Have Prevented Them

A series of real examples drawn from Paul’s expert witness investigations into failed patios, terraces, lawns, retaining structures and non-compliant drainage installations.

Each case highlights what went wrong, why it happened, and how correct detailing, material choice and adherence to the updated standards would have prevented the issue.

A practical, experience-led session designed to help designers build resilience into their work.

Recordings and slides will be provided to attendees after the full series concludes. The slides will only relate to the talk and Paul’s knowledge and projects he has built etc and should not be used as a guide for other people’s projects.

Important Note

General questions are welcome, but project-specific drainage advice cannot be given during these sessions, as full site details would be required. Paul will be happy to be contacted for assistance, but unless engaged as a consultant, it may take some time for Paul to respond.

Paul Greenyer

Paul Greenyer began his career as a design engineer, working for 15 years across technical and manufacturing sectors before establishing InsideOut Home & Garden Improvements in 2016. Originally focused on domestic construction and home improvement, his work naturally evolved into garden and landscape design, leading him to join both the Society of Garden Designers (SGD) and the Association of Professional Landscapers (APL), where he remains an active member.

Over the past five years, Paul has benefited from the mentorship of Alan Sargent, one of the UK’s most respected landscaping professionals. This guidance deepened his understanding of the industry as a whole, helping him recognise recurring technical failures, weak detailing, contractual misunderstandings and the common causes of landscape disputes. This experience created a natural pathway into expert witness work.  Determined to raise standards within the domestic landscaping sector, Paul completed formal training with the Royal Institution of Chartered Surveyors (RICS) in Expert Witness practice and Evaluative Mediation. He is now an accredited RICS Expert Witness and Mediator, providing consultancy, expert reporting, dispute resolution and training through Paul Greenyer Consultancy Ltd.  Paul’s approach to teaching and consultancy blends his engineering background, landscaping and design experience, and his expert witness casework. He brings additional focus on emerging industry standards, including the new BS 7533-102 and BS 7533-103, which cover paving strata, construction layers, laying systems, bond bridges, bedding mortars, moisture management, capillary action and overall water movement across a site.  He hopes to incorporate these technical insights into the four talks, helping designers better understand how drainage interacts with construction methods, moisture pathways and the wider SuDS landscape.

Paul also comes from deep horticultural roots. His family once operated Greenyer Brothers Nurseries in Worthing, part of the historic glasshouse movement, and the Greenyer horticultural lineage in Sussex dates back to 1706. Although the nurseries no longer exist, his love of plants, growing and gardens is still very much alive. He has spent the past four years slowly building his own garden, and he also enjoys tending his allotment when he can. In 2020, Paul raised funds for the horticultural charity Perennial by appearing in their 2023 “Naked Gardeners” calendar, a light-hearted but meaningful contribution to an industry he cares deeply about.

Paul proposed to his beautiful wife Laura at the 2022 RHS Chelsea Flower Show in the ‘With Love’ garden by Richard Miers.

Coming up in 2026, along with 2 colleagues, Paul will be revealing far more than a bit of flesh; he’ll be raising a discussion within the industry on neurodiversity and hoping to dispel some of the myths around it and ways we can help ourselves, our staff and our community as a whole.