51a, Harmer Green Lane, Welwyn, AL6 0AP
About 51a
51a is a detached house in Welwyn (AL6 0AP). It has a recorded floor area of 672 m² (around 7233 sq ft) and construction records dating it to 2024. The latest certificate (March 2025) returns an A (score 92), the top energy band on the EPC scale. Main heating runs on electricity: electricity, unspecified tariff.
Held since September 1998 — that's 28 years off the open market, well above the local norm. Only one transfer is on record with HM Land Registry, suggesting it has stayed in the same hands for a long time. At 672 m² the property is well over the postcode median (423 m² across 6 EPCs), placing it in the larger end of the local stock. On energy efficiency it sits in the top 10% of properties in this postcode. Today's modelled estimate of £4,067,000 sits 364.8% above the 1998 sale of £875,000. On a £-per-square-foot basis, the last sale (£121/sq ft) was about 67.1% below the postcode norm. One historical planning record sits against the property in 2013.
Know exactly what you're buying at 51a
Before you offer, see what the listing won't tell you, the true value, the red flags and the full history.
Already flagged here
Valuation
against the asking price
Risks
planning & flood
Sold prices
similar homes nearby
Trends
the local market
Energy performance
51a ranks among the most efficient homes in the postcode for energy use.
EPC Rating
Planning history
- Jun 2013ConditionsIn report
Discharge of conditions 7 (Landscape Method) N6/2012/1090/FP - Erection of two detached dwellings (House A & B) following demolition of existing
- Reference
- N6/2013/0944/DS
We flagged 1 thing worth checking at 51a
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.
- Larger development activity nearby
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Sales history & valuation
51a's modelled value sits at over four times its earliest registered sale price (1998).
£4,067,000
Modelled from EPC, postcode comparables.
£875,000
Recorded with HM Land Registry.
Sales timeline
2 September 1998Most recent
£875,000
Median price across the last 5 sales in AL6 0AP: £2,080,000 (2023–2006).
Nearby sales in AL6 0AP
Everything we know about 51a, in one report
What it's really worth, what could be wrong, and the planning, sales and area data in full.
What we flagged
- Larger development activity nearby
Versus other Harmer Green Lane homes
51a is notably below the street on price per m².
Price per m²
£1,302
Street avg £4,688
Floor Area
672 m²
Street avg 402 m²
CO₂ Emissions
0.9 t/year
Street avg 9.4 t/year
Years Held
28 years
Street avg 8 years
Similar properties nearby
The neighbourhood at a glance
Rail-style transport is unusually close for this postcode.
Crime
2/mo
Steady year-on-year across the wider district.
Nearest stop
0.3 km
New Road — bus stop.
Closest school
1.2 km
St John's CofE Primary School. 12 schools nearby.
Go deeper on the local area
The full report breaks down crime, transport links, schools and air quality in depth.