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21 Underdown Road, Southwick, Brighton, BN42 4HN

3 sales on record1 planning record

Estimated value

£507,000

  • Since the 2021 sale (£445,000)+14%
  • Against BN42 4HN's recent median (£405,000)+25%

Newest record on this page: July 2026. Land Registry and EPC registers update monthly, so this page can trail them by 2–3 months.

Learn about this valuation
Property type
Semi-detached
Bedrooms
3
Floor area
117 m²
1259 sq ft
Energy rating
D
Score 67
Council tax
Band D
Tenure
Owner Occupied
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Valuation

About this valuation

How the figure is worked out and what it's based on. If you know this home, you can tell other visitors what you think it's worth.

Our estimate

£507,000

  • Against its 2021 sale (£445,000)+14%
  • Against BN42 4HN's recent median (£405,000)+25%

Your note and figure are shown publicly on this page.

How the estimate is made

The estimate for 21 Underdown Road is modelled from its 117 m² EPC floor area, its 3 recorded sales and recent sales of comparable homes in BN42 4HN. It is an automated estimate, not a survey or mortgage valuation: condition, layout and improvements that aren't on record can move the real figure either way.

What it's based on

  • Floor area

    117 m² from the EPC lodged in July 2026

  • Sales of this home

    3 sales recorded, the latest in 2021

  • Recent sales in BN42 4HN

    5 sales, median £405,000 (2025–2021)

This page or the full report?

DataThis pageFull report
SalesLatest sale shown: February 2025Latest available records, read when you order
ValuationEstimate from the last refreshAnalysed against comparable sales
Planning1 applicationFull history, plus nearby schemes
Flood riskNot shownIncluded
Price

Sales history & valuation

Every recorded sale of this home, how its price has moved, and what neighbouring properties have sold for.

Price for 21 Underdown Road has grown more than fourfold since the 1999 starting point.

Sales timeline

  1. 10 December 2021Most recent

    £445,000

    +93.5%over 11 years

  2. 22 January 2010

    £230,000

    +150.1%over 10 years

  3. 9 December 1999

    £91,950

Median price across the last 5 sales in BN42 4HN: £405,000 (2025–2021).

Risks

What this page doesn't show

Nothing is flagged from the data on this page, but these checks are only run in the report. The detail, evidence and what to ask about it are in the Risks Report.
  • Flood risk from rivers, sea and surface waterIn report
  • Subsidence and ground-stability signalsIn report
  • Refusals, enforcement and big schemes nearbyIn report

One time fee only - money back guarantee

Overview

About 21 Underdown Road

A plain-English summary derived from public records, EPC certificates, sold prices and local data.

21 Underdown Road is a three-bedroom semi-detached house in Southwick, Brighton, Brighton (BN42 4HN). It has a recorded floor area of 117 m² (around 1259 sq ft), construction records dating it to 1900-1929 and council tax band D. The latest certificate (July 2026) shows a D (score 67), on the cusp of jumping into the C band. When first surveyed in June 2009 the rating was E, the property has climbed 1 band since. Between certificates, window efficiency went from Poor to Average, hot-water efficiency went from Poor to Good and lighting went from Poor to Good; while roof efficiency dropped from Good to Very Poor. The recommended improvements would lift it to B (score 81), a 2-band jump. This certificate was lodged in the last six months, so the rating reflects current condition. Period features are noted in the property record.

At 117 m² the property is well over the postcode median (70 m² across 40 EPCs), placing it in the larger end of the local stock. Across 1999–2021, sale prices on this property compounded at 7.4% per year. Today's modelled estimate of £507,000 is 13.9% above the 2021 sale price. On a £-per-square-foot basis, the last sale (£353/sq ft) was about 54% above the typical sold price in the postcode. Last sale on file: £445,000 in December 2021. That sale was during the post-pandemic price surge, when transactions cleared materially above pre-2020 trend. One historical planning record sits against the property in 2022.

Specifications

What this property has

Pulled from EPC certificates, claim submissions and our property model. Empty categories are hidden — we only show what's known.

Inside

  • Bedrooms3
  • Dining roomYes
  • FireplaceYes

Outside

  • Private gardenWest-facing
  • DrivewayYes

Building

  • Period featuresYes
  • RefurbishedYes
Before you decide

Everything you need to know about 21 Underdown Road

The true value, the hidden risks and the full sale history, in one report.

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Preview of the full property report

The data behind every report

  • HM Land Registry, source of sold price history
  • Department for Education, source of schools data
  • Police.uk, source of crime statistics
  • Department for Transport, source of stations and transport links
  • Environment Agency, source of flood risk data
  • Department for Environment, Food & Rural Affairs, source of road noise data
  • PlanIt, source of planning application records
Energy

Energy performance

Every EPC certificate filed against this property — current rating, recorded improvements, and where there's headroom to reach a higher band.

Recommended upgrades on file would lift this property by multiple EPC bands.

Current Certificate(1 of 3)
Jul 2026

EPC Rating

A
B
C
D
D67
E
F
G
Main Heating
Gas
Main Fuel
Gas
Hot Water
Good
Windows
Average
CO2 Emissions
4.1 t/year
Occupancy
Owner Occupied

Certificate validity

Valid until 30 July 2036

9 years remaining

Property Improvements

Changes detected from historical EPC data

Jul 2019from Jun 2009
EPC improved fromE43toD59
Heating Controls
Prog + TRVsFull

Heating controls upgraded for better temperature management

Hot Water
Main (No Stat)Main System

Hot water system upgraded

Windows
Partial DoubleFull Double

Windows upgraded, improving insulation

Roof Insulation
InsulatedWell Insulated

Loft insulation upgraded to recommended levels

Low Energy Lighting
15%100%

More low energy lighting installed

Planning

Planning history

Applications and permits filed against 21 Underdown Road, Southwick, Brighton, BN42 4HN, sourced from the PlanIt planning register.

1 application on record at 21 Underdown Road, Southwick, Brighton, BN42 4HN

1decisions7documents2nearby
  1. Nov 2022
    Outline
    Outcome in report

    Application for a Certificate of Lawfulness for a proposed dormer extension to rear and installation of roof lights to front elevation.

    Documents
    7 docs on file
    Reference
    AWDM/1623/22
    Full record in report

Unlock 21 Underdown Road, Southwick, Brighton, BN42 4HN's full planning history

You're seeing the shape of it. The report has the substance.

  • Every decision — granted, refused or withdrawn (1 on record)
  • All 1 application on this property in full, plus 2 notable nearby
  • The 7 documents, officer reports & conditions
  • What the pattern means for extending or converting here
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On the street

Versus other Underdown Road homes

Four headline reads against 21 similar houses on this street, drawn from the latest EPC and Land Registry data.

21 Underdown Road is notably below the street on years held.

Price per m²

£3,803

Street avg £3,905

On par

Floor Area

117 m²

Street avg 110 m²

Above

Habitable Rooms

5 rooms

Street avg 5 rooms

On par

CO₂ Emissions

4.1 t/year

Street avg 5.3 t/year

On par
Area

The neighbourhood at a glance

A condensed read of the local area. Each tile links through to the full breakdown on the Brighton district page.
Full Brighton report

Rail-style transport is unusually close for this postcode.

Crime

45/mo

Falling year-on-year across the wider district.

Nearest stop

0.2 km

St Theresa's Church — bus stop.

Closest school

0.5 km

Shoreham Academy. 16 schools nearby.

Nearest schools

  • Shoreham AcademySecondary516m
  • Glebe Primary SchoolPrimary544m
  • Holmbush Primary AcademyPrimary714m
  • Eastbrook Primary AcademyPrimary828m

Nearest stops

  • St Theresa's ChurchBus stop176m
  • Kingston LaneBus stop270m
  • Cross RoadBus stop329m
  • Kingston BroadwayBus stop372m

Most reported crime locally

  • Violence & Sexual Offences226 reports36%
  • Anti-social Behaviour105 reports17%
  • Public Order58 reports9%
  • Criminal Damage & Arson57 reports9%

Go deeper on the local area

A Local Area report breaks down crime, transport links, schools and air quality in depth.

Noise

Road noise across the postcode

Modelled day and night-time noise levels around BN42 4HN from Defra's strategic mapping. The pin marks this postcode's centroid.
Daytime road noise heatmap for BN42 4HN

Daytime· 07:00 – 23:00

52.3dB

Low
Night-time road noise heatmap for BN42 4HN

Night-time· 23:00 – 07:00

42.3dB

Low
55 dB
60 dB
65 dB
70 dB
75 dB
80 dB
Defra Road Noise Strategic Mapping, Round 4
SDL Surveying

Get a survey for this property

Level 3 Building Survey

Victorian-eraSemi-Detached HouseEPC DPre-1919 buildSolid (non-cavity) walls

Because the property was built before 1919 and has solid (non-cavity) walls, we believe a Level 3 building survey should be considered.

From £1,085 · Includes VAT

Comparables

Similar properties nearby

A handful of close matches in the same postcode area, ranked by likeness on bedrooms, type and floor area.
£477k

1 Hill Farm Way, Southwick

BN42 4YJ

3 bed1 bath
£557k

1 Hill Farm Cottages, Upper Kingston Lane, Southwick

BN42 4YN

3 bed
£614k

1 Albert Road, Southwick

BN42 4GE

3 bed2 bath
£415k

1 Farm Way, Southwick

BN42 4NU

3 bed2 bath
£415k

1 Green Close, Southwick

BN42 4GR

3 bed
£512k

1 Downland Close, Southwick

BN42 4RH

4 bed2 bath
£390k

1 Cardigan Villas, Southwick

BN42 4GG

2 bed1 bath
£294k

1 Green Court, The Green, Southwick

BN42 4GS

2 bed

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Method

How to read this page

Where every figure above comes from, how current it is and what it can't tell you.
Valuation method in detail
How the estimate is made
The estimate for 21 Underdown Road is modelled from its 117 m² EPC floor area, its 3 recorded sales and recent sales of comparable homes in BN42 4HN. It is an automated estimate, not a survey or mortgage valuation: condition, layout and improvements that aren't on record can move the real figure either way.
Where sold prices come from
Sold prices are HM Land Registry Price Paid Data, which covers residential sales in England and Wales since 1995. 3 sales are recorded for 21 Underdown Road. Sales normally appear two to three months after completion, so the most recent ones take time to show up anywhere.
Reading the EPC
Energy Performance Certificates rate homes from A (most efficient) to G and last 10 years. The latest one for 21 Underdown Road was lodged in July 2026 at band D and is valid until July 2036. 3 certificates are on record, which shows how the home has changed.
Planning records
Planning applications are collected from local authority registers through PlanIt. 1 application is matched to 21 Underdown Road. Councils sometimes file applications under a different address format, and applications on neighbouring land aren't listed here; the report covers both.
Area figures
Crime is police-recorded street-level data over the last 14 months, which places each incident at an approximate point. The 16 schools and 30 stops listed are measured in a straight line from BN42 4HN, not by walking route. Road noise is Defra's strategic noise modelling, averaged across the postcode.
Council tax band
21 Underdown Road is in council tax band D. Bands are set by the Valuation Office Agency from historic values (1 April 1991 in England, 1 April 2003 in Wales), not today's price; the amount you pay depends on the council's rate for the band.
FAQ

Common questions

The questions buyers, sellers and homeowners most often ask about 21 Underdown Road, Southwick, Brighton, BN42 4HN. Each answer is also embedded as structured data for search engines.

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