House and office – SuDS retrofit

Tell us about your project: 4 Green Roofs, Hydration Channel, Water butts at every downspout, additional 1m³ IBC tank, Rain garden/pond, Permeable driveway.

Where?: Fairly standard 70’s detached house/garden office and domestic landscape, in a rural East Yorkshire village. Total plot size approx. 0.1 hectares

When?: The scheme has developed over time – the oldest green roof is about 13 years old, the newest interventions are about 4 years old.

Design and implementation: 2B’s office is in the garden of our Directors’ house. 

Over a decade-ish, the property has been retrofitted in every way to catch and manage rainfall, to learn first-hand about constructing and living with SuDS. 

Two larger green roofs (garage/office), and two on sheds, experiment with different constructions and planting styles. 

A crated hydration channel does a specific job, preventing the insurance company felling a mature tree, by ‘attracting’ tree roots. It receives rain water from a major part of the house roof, distributes it into an underground channel, and allows water to permeate.

Every downspout is diverted via water butt; from a typical domestic one, to two large rectangular butts. The ‘pièce de résistance’ is a 1m³ IBC tank, mounted on brick pillars and fed by the house roof. This has been incorporated into a fencing/pergola system at the side of the house.  

Overflow from all water butts runs into either the hydration channel at the front, or rain garden at the rear of the house.

The rain garden takes rainfall from impermeable roof and patio areas, via a pond made from an old bathtub, to a depression in the lawn. The contingency overflow is a bordering agricultural ditch.

More detail available at

Benefits and constraints: The scheme performs really well on all 4 pillars of SuDS (Water quantity, quality, amenity and biodiversity), we’re very pleased with it. 

The only downside is that we can’t control what happens outside of our property boundary…we have flooded since these interventions, when a substantial overland flow of rainwater from already-saturated fields, which ran down our lane and across ours and our neighbours’ drives. This is why we need a whole catchment approach (and one of the reasons we have set up West Wolds Slow The Flow! See

Further opportunities: We think we’ve done just about everything possible!

Costs: It’s varied over time, and a bit hard to say: we’ve done it when we were doing other work anyway, e.g. when we were building an office, we chose a green roof, when we needed the drive doing, we chose permeable paving…

Who?: 2B Landscape Consultancy Ltd / Bill and Elizabeth Blackledge