5 Castilian Street, Northampton, NN1 1JS

5 Castilian Street is a mid-terrace house in Northampton (NN1 1JS). It has a recorded floor area of 155 m² (around 1668 sq ft), construction records dating it to 1996-2002 and council tax band C. The latest certificate (November 2023) shows a D (score 63), on the cusp of jumping into the C band. When first surveyed in December 2009 the rating was E, the property has climbed 1 band since. Between certificates, roof efficiency went from Average to Very Good and lighting went from Poor to Very Good; while hot-water efficiency dropped from Very Good to Good and main heating dropped from Very Good to Good. The recommended improvements would lift it to B (score 85), a 2-band jump.

At 155 m² the property is well over the postcode median (54 m² across 13 EPCs), placing it in the larger end of the local stock. On the market in December 2017 and unlisted since — roughly 9 years. Across the public record there are 6 sales, relatively high churn for a single property. Across 1997–2017, sale prices on this property compounded at 6.3% per year. Today's modelled estimate of £327,000 is 14.7% above the 2017 sale price. On a £-per-square-foot basis, the last sale (£171/sq ft) was about 31% below the postcode norm. One planning record on file: HMO conversion refused in 2018.