What kind of home is 20 William Street, SA9 1AT?

20 William Street, SA9 1AT is a 3-bedroom mid-terrace house, set on a cul-de-sac.

What was the last sold price for 20 William Street, SA9 1AT?

20 William Street, SA9 1AT last sold for £125,000 in December 2023, around 2 years ago. Land Registry has 3 sales on record going back to £110,000 in September 2007. Source: HM Land Registry.

Has 20 William Street, SA9 1AT appreciated in value?

Across 3 sales between September 2007 and December 2023, 20 William Street, SA9 1AT rose from £110,000 to £125,000, a change of £15,000. That works out to roughly +0.8% per year compounded over 16 years. Source: HM Land Registry.

What energy rating does 20 William Street, SA9 1AT have?

The current EPC rating for 20 William Street, SA9 1AT is D with a score of 64 out of 100, lodged in December 2022. The assessor estimates the property could reach a B. Source: EPC Register.

How big is 20 William Street, SA9 1AT?

20 William Street, SA9 1AT has a recorded floor area of 76 m² (818 sq ft), around 25 m² per bedroom. That makes it about 11% smaller than the median EPC-recorded property in SA9 1AT. Source: EPC Register.

What heating system does 20 William Street, SA9 1AT use?

The latest EPC at 20 William Street, SA9 1AT records mains gas as the main heating fuel. Source: EPC Register.

What is the council tax band for 20 William Street, SA9 1AT?

20 William Street, SA9 1AT is in council tax band B. That sits at the lower end of the A-H ladder, typically reflecting smaller floor areas or lower 1991 valuations.

Which area is 20 William Street, SA9 1AT in?

20 William Street, SA9 1AT sits in Ystradgynlais, Swansea, Swansea. It falls within the SA9 postcode district.

Is 20 William Street, SA9 1AT in a safe area?

Police records around 20 William Street, SA9 1AT show an average of 6 reported crimes per month over the last 9 months. Violent crime makes up roughly 72% of reports, the most common category. The overall trend is broadly stable. Source: Police UK.

How well connected is 20 William Street, SA9 1AT?

The closest bus stop to 20 William Street, SA9 1AT is Glanrhyd Hospital, 80m away. In total there are 30 bus stops within the surrounding area.

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20 William Street, Ystradgynlais, Swansea, SA9 1AT

3 sales on record

Property type

Mid terrace

Bedrooms

Bathroom

Floor area

76 m²

818 sq ft

Energy rating

Score 64

Council tax

Band B

Tenure

Owner Occupied

Overview

About 20 William Street

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

20 William Street is a three-bedroom mid-terrace house in Ystradgynlais, Swansea, Swansea (SA9 1AT). It has a recorded floor area of 76 m² (around 818 sq ft), construction records dating it to 1930-1949 and council tax band B. The latest certificate (December 2022) shows a D (score 64), on the cusp of jumping into the C band. The recommended improvements would lift it to B (score 85), a 2-band jump. The home occupies a cul-de-sac position.

Across 2007–2023, sale prices on this property compounded at 0.8% per year. Today's modelled estimate of £164,000 is 31.2% above the 2023 sale price. On a £-per-square-foot basis, the last sale (£153/sq ft) was about 71.3% above the typical sold price in the postcode. Sold December 2023 for £125,000.

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Valuation

against the asking price

Risks

planning & flood

Sold prices

similar homes nearby

Trends

the local market

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
Bathrooms1

Outside

Private gardenYes
Cul-de-sacYes

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.

EPC Rating

D64

Main Heating

Gas

Main Fuel

Gas

Hot Water

Good

Windows

Average

CO2 Emissions

3.9 t/year

Occupancy

Owner Occupied

Planning

Planning history

Applications and permits filed against 20 William Street, Ystradgynlais, Swansea, SA9 1AT, sourced from the PlanIt planning register.

20 William Street has no planning applications on record.

Notable planning nearby

2applications of note in the surrounding area

Before you offer

We flagged 1 thing worth checking at 20 William Street

Independent checks surfaced things a buyer would want to understand before offering. The report explains each one in full, with the underlying data and what to ask.

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Price

Sales history & valuation

Recorded transactions, our model's current estimate, and a quick read on what neighbouring properties have sold for.

20 William Street's sale-price growth has lagged the wider UK trajectory across its history on file.

Current estimate

£164,000

Modelled from EPC, postcode comparables and a sale-price growth of 0.8% per year over 16 years.

See how we calculated this

Last sold (2023)

£125,000

Growth on file: 0.8% per year over 16 years.

Sales timeline

15 December 2023Most recent
£125,000
+43.7%over 8 years
22 December 2014
£87,000
-20.9%over 7 years
20 September 2007
£110,000

Median price across the last 5 sales in SA9 1AT: £127,000 (2025–2019).

Nearby sales in SA9 1AT

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Everything we know about 20 William Street, in one report

What it's really worth, what could be wrong, and the planning, sales and area data in full.

What we flagged

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On the street

Versus other William Street homes

Four headline reads against 13 similar houses on this street, drawn from the latest EPC and Land Registry data.

20 William Street outperforms the street on price per m² by a wide margin.

Price per m²

£1,645

Street avg £1,053

Strongly above

Floor Area

76 m²

Street avg 88 m²

Below

Habitable Rooms

4 rooms

Street avg 5 rooms

Below

CO₂ Emissions

3.9 t/year

Street avg 5.0 t/year

Above

Comparables

Similar properties nearby

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

£188k

1 Caehopkin Cottage, Caehopkin Road, Abercrave

SA9 1TX

3 bed1 bath

£240k

1 2 Metz Cottages, Ystradgynlais

SA9 1SB

3 bed1 bath

£248k

1 Abercrave Villas, Heol Tawe, Abercrave

SA9 1TN

3 bed

£256k

1 Brynygroes Cottages, Ystradgynlais

SA9 1LE

3 bed

£272k

1 Brynawel Villas, Brecon Road, Ystradgynlais

SA9 1HQ

3 bed

£164k

1 Brooklands Terrace, Abercrave

SA9 1UF

2 bed

£154k

1 Brewers Cottage, Pelican Street, Ystradgynlais

SA9 1LG

2 bed

£194k

1 Coedlan, Lower Cwmtwrch

SA9 1ED

4 bed

Area

The neighbourhood at a glance

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

Full Swansea report

Crime

6/mo

Steady year-on-year across the wider district.

Nearest stop

0.1 km

Glanrhyd Hospital — bus stop.

Go deeper on the local area

The full report breaks down crime, transport links, schools and air quality in depth.

Map

Everything within walking distance

Schools, transport stops and scenic spots near this property — 30 points of interest in total.

FAQ

Common questions

The questions buyers, sellers and homeowners most often ask about 20 William Street, Ystradgynlais, Swansea, SA9 1AT. Each answer is also embedded as structured data for search engines.