Flat 1, 25 Castilian Street, Northampton, NN1 1JS
About Flat 1
Flat 1 is a semi-detached house in Northampton (NN1 1JS). It has a recorded floor area of 68 m² (around 732 sq ft) and construction records dating it to 2012 onwards. At 68 m² this is the largest unit on EPC record across the building (53–68 m²). The building's EPC ratings span E to D, with this unit at the bottom. The latest certificate (June 2025) shows an E (score 53), well below the UK norm with real room to improve. The rating has held steady at E across 2 certificates since February 2015. Between certificates, wall efficiency went from Average to Very Good. The recommended improvements would lift it to C (score 74), a 2-band jump. Main heating runs on electricity.
At 68 m² it's 25.9% larger than the typical home in the postcode (54 m² median across 13 EPCs). On energy efficiency it sits in the bottom 10% of properties in this postcode — significant headroom for improvement.
Everything you need to know about Flat 1
The true value, the hidden risks and the full sale history, in one report.
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Energy performance
Flat 1 sits at the bottom of the postcode for energy efficiency — meaningful headroom to improve.
EPC Rating
Property Improvements
Changes detected from historical EPC data
Wall insulation improved
Get a survey for this property
Level 3 Building Survey
Because the property has no mains gas supply and has solid (non-cavity) walls, we believe a Level 3 building survey should be considered.
From £820 · Includes VAT
Planning history
Flat 1 has no planning applications on record.
But the area is active
45 notable applications nearby — larger schemes and conversions that could reshape the street. The report maps them all.
Sales history & valuation
Flat 1 has no Land Registry sales on file, suggesting it has stayed in the same hands since registration began.
£176,000
Modelled from EPC, postcode comparables.
No sales recorded with HM Land Registry
That can mean the property has never traded since the registry began publishing in 1995, was a new build that hasn't been registered yet, or is held in the same hands long-term.
Median price across the last 5 sales in NN1 1JS: £225,000 (2025–2016).
Nearby sales in NN1 1JS
Flat 1, 9 Castilian Street, Northampton, NN1 1JS
Sold Mar 2025
£225,0005 Castilian Street, Northampton, NN1 1JS
Sold Dec 2017
£285,000Flat 2, 7 Castilian Street, Northampton, NN1 1JS
Sold Jun 2017
£99,450Flat 3, 7 Castilian Street, Northampton, NN1 1JS
Sold Mar 2016
£113,500Flat 1, 7 Castilian Street, Northampton, NN1 1JS
Sold May 2015
£120,000
Versus other Castilian Street homes
On floor area, Flat 1 stands well clear of the street.
EPC Rating
53 (E)
Street avg 68 (D)
Floor Area
68 m²
Street avg 52 m²
CO₂ Emissions
3.5 t/year
Street avg 2.1 t/year
Habitable Rooms
3 rooms
Street avg 2 rooms
Everything you need to know about Flat 1
The true value, the hidden risks and the full sale history, in one report.
Pick your report · every report is £14.99
One time fee only - money back guarantee
The data behind every report
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The neighbourhood at a glance
Reported crime in the wider district is trending notably upward year-on-year.
Crime
11/mo
Rising year-on-year across the wider district.
Nearest stop
0.1 km
Post Office — bus stop.
Closest school
0.8 km
Spring Lane Primary School. 32 schools nearby.
Go deeper on the local area
A Local Area report breaks down crime, transport links, schools and air quality in depth.
Road noise across the postcode
Daytime· 07:00 – 23:00
57.0dB
Night-time· 23:00 – 07:00
47.6dB