Planning drawings in Three Rivers, £895 fixed

What is the householder approval rate in Three Rivers?

Three Rivers District Council granted 561 of 617 householder decisions (90.9%) from 1 July 2025 to 30 June 2026, counting householder planning applications and larger home extension prior approvals together. Across London the same measure was 85.8% (20,556 of 23,967). Source: MHCLG live table PS2, district planning application statistics, 1 July 2025 to 30 June 2026. See the other Hertfordshire councils on the Hertfordshire planning page.

What does Three Rivers District Council need to validate an application?

• Every application, householder included, needs the council's completed Local Biodiversity Checklist with its conclusion (Part D of the validation checklist adopted 1 August 2024). (source)
• A street scene elevation for any extension that raises the ridge height, showing the buildings either side. (source)
• Existing and proposed plans and elevations at 1:50 or 1:100, each drawing showing paper size, scale and a scale bar. (source)
• A tree survey where there is a Tree Preservation Order, a conservation area, or trees on or next to the site over 75mm in diameter. (source)
• In the Moor Park Conservation Area, any basement needs a flood risk assessment covering underground watercourses. (source)

Article 4 directions in Three Rivers

An Article 4 direction removes permitted development rights, so work that needs no application elsewhere needs one here. Check yours with the permitted development checker.

• Chorleywood Common Conservation Area. Some normally permitted alterations need permission, including windows, chimneys, front boundaries and hardstanding. (source)
• Moor Park Conservation Area. A direction, published with the conservation area appraisal, restricts permitted development rights. (source)
• Chorleywood Station Estate Conservation Area (2006). A 2006 direction removes some permitted development rights. (source)
• Loudwater Estate (2002) and Trout Rise Farm, Loudwater. Directions restrict permitted development rights at both. (source)
• Dickinson Square, Croxley Green (1996). A 1996 direction restricts permitted development rights. (source)
• Nightingale Road and Upper Nightingale Road. Two directions in the Upper Nightingale Road and Cedars Avenue Conservation Area. (source)

The council says there are 22 conservation areas in Three Rivers, from Rickmansworth and Moor Park to Sarratt and Chorleywood Common. (source)

How long does a planning decision take in Three Rivers?

Eight weeks is the statutory period for a householder application. Of the 503 householder planning applications Three Rivers decided from 1 July 2025 to 30 June 2026, excluding prior approvals, 494 (98.2%) were decided within eight weeks.

• The council aims to decide applications within eight weeks of validation (13 for major applications); neighbours get at least 21 days to comment. (source)
• From 1 April 2026, householder pre-application advice costs £115 including VAT for a site visit and written note, aiming to visit within 10 and reply within 25 working days. (source)

Design guidance: Development Management Policies LDD (2013), Appendix 2: Design Criteria. Single-storey rear extensions generally up to 3.6m deep (4m for detached houses), first-floor side extensions at least 1.2m off the boundary, and a 45-degree splay for two-storey rear extensions.

Other local costs and documents in Three Rivers

• The council offers a free householder duty planner service in addition to paid pre-application advice. (source)
• The development plan is the Core Strategy (2011), Development Management Policies LDD (2013) and Site Allocations (2014), plus neighbourhood plans for Croxley Green, Chorleywood, Batchworth, Sarratt and Abbots Langley. (source)

Planning and building regulations drawings in Three Rivers

The same published prices apply in Three Rivers as everywhere we work.

• fixed-fee planning drawings: £895, survey to submission, with the council fee paid separately.
• full plans drawings for building control: £795, drawn to the Approved Documents once planning is settled.
• check what an extension needs: what a rear, side or wraparound extension needs, from permitted development to a full application.

Where your work is permitted development, a certificate of lawfulness starts at £950. Not sure which applies? Read do I need planning permission? first.

Neighbouring councils

Three Rivers shares a boundary with four council areas where we publish the same council data. Each has its own approval rate, validation checklist and Article 4 areas, so check which council your address falls under before relying on any one page.

Council facts checked 13 October 2026.