About the Old Knebworth Conservation Area
The Old Knebworth Conservation Area covers about 53 hectares and was designated by North Hertfordshire District Council in 2008. Inside the boundary are 30 listed buildings (1 Grade I, 1 Grade II*, 28 Grade II). The most significant is Church of St Mary and St Thomas, Grade I.
What changes inside the conservation area
Conservation areas are “Article 2(3) land”. You keep most permitted development rights, but these are removed or tightened.
- Rear extensionElsewhere: 3 m · 6 m with PANo 6 m / 8 m prior approval
- Two-storey extensionElsewhere: 3 mNeeds planning permission
- Side extensionElsewhere: Half the widthNeeds planning permission
- Loft conversionElsewhere: 50 m³Needs planning permission
- Garden roomElsewhere: 2.5 m high by boundariesNot beside the house
- PorchElsewhere: 3 m²Same limits
- Solar panelsElsewhere: 0.2 m projectionSame limits
- Air source heat pumpElsewhere: 1 unitNot facing the road
- Fences, walls and gatesElsewhere: 2 m · 1 m by a roadSame limits
- External claddingElsewhere: Matching materialsNeeds planning permission
- Tree workElsewhere: No notice6 weeks’ notice to the council
- Demolition (over 115 m³)Elsewhere: AllowedNeeds planning permission
Limits for a semi-detached house under the GPDO 2015. An Article 4 direction can remove more.
Listed buildings in the conservation area
Any work affecting these needs listed building consent, inside or out. Each links to its entry on the National Heritage List.
- Church of St Mary and St ThomasGrade I
- Knebworth HouseGrade II*
- 1 of 6 Tombs in Churchyard of St Mary and St Thomas A to Leonara Robinson LyttonGrade II
- 1 of 6 Tombs in Churchyard of St Mary and St Thomas C to Kenneth Gray BuchananGrade II
- 1 of 6 Tombs in Churchyard of St Mary and St Thomas D to Marion Mackinnon BuchananGrade II
- 1 of 6 Tombs in Churchyard of St Mary and St Thomas E to Edgar and Beryl LafoneGrade II
- 1 of 6 Tombs in Churchyard of St Mary and St Thomas: F Memorial to Anthony James, Viscount KnebworthGrade II
- 1 of 6 Tombs in Churchyard of St Mary and St Tomas B Tombstone to Alice Louisa SleathGrade II
- 188 and 190, Park LaneGrade II
- Barns at Glebe HouseGrade II
- Church LodgeGrade II
- Crom CottageGrade II
- Estate Office, Garage and Cottage, Including Garden Wall at RearGrade II
- Garden Wall, Gates and GatepiersGrade II
- Gardeners LodgeGrade II
- Gates and Gatepiers of King George V Playing FieldGrade II
- Inn CottageGrade II
- Jubilee Lodges, Walls and Gate PostsGrade II
- Knebworth War MemorialGrade II
- Lytton Almshouses (5 Dwellings)Grade II
- Manor Farm CottageGrade II
- Manor Gardens CottageGrade II
- Manor HouseGrade II
- Milepost at Junction of Driver's End Lane and Park LaneGrade II
Show all 30 listed buildings ↓All 30 listed buildings
- Mulberry CottagesGrade II
- Mulberry Tree CottageGrade II
- Nup End Farm CottagesGrade II
- Nup End FarmhouseGrade II
- Park Gate HouseGrade II
- Sheep ShearersGrade II
The council’s appraisal
WEBOld Knebworth Conservation Area AppraisalNorth Hertfordshire District Council’s description of the area’s character — what planners look at when you apply.Open on council site ↗Nearby conservation areas
Boundary and listed buildings from North Hertfordshire District Council and Historic England via planning.data.gov.uk (OGL). Guidance only — not an official council check.