10 Harmer Green Lane, Welwyn, AL6 0AX
About 10 Harmer Green Lane
10 Harmer Green Lane is a four-bedroom detached house in Welwyn (AL6 0AX). It has a recorded floor area of 106 m² (around 1141 sq ft), construction records dating it to 1950-1966 and council tax band F. The latest certificate (July 2021) shows a D (score 62), on the cusp of jumping into the C band. When first surveyed in January 2009 the rating was F, the property has climbed 2 bands since. Between certificates, roof efficiency went from Very Poor to Average, hot-water efficiency went from Average to Good and lighting went from Good to Very Good. The recommended improvements would push it to C (score 79). Other recorded features include attached land beyond the plot.
3 planning records sit against the property, 3 approved, 0 refused. Past consents include an extension, meaningful when judging how the property has evolved. Across 2009–2022, sale prices on this property compounded at 6.4% per year. On a £-per-square-foot basis, the last sale (£701/sq ft) was about 33.2% above the typical sold price in the postcode. Sold October 2022 for £800,000. That sale was during the post-pandemic price surge, when transactions cleared materially above pre-2020 trend.
Know exactly what you're buying at 10 Harmer Green Lane
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
What this property has
Inside
- Bedrooms4
- Bathrooms2
- Open-plan layoutYes
- Dining roomYes
- EnsuiteYes
- StudyYes
Outside
- ParkingYes
- LandYes
Energy performance
EPC Rating
Property Improvements
Changes detected from historical EPC data
Hot water efficiency improved
Loft insulation installed or upgraded to 250mm+
More low energy lighting installed
Planning history
- May 2023ExtensionFullIn report
Erection of two storey rear extension, single storey side and front extensions, front and rear dormer windows, increased roof ridge heights, elevational alterations and conversion of garage to provide ancillary living accommodation to the main house.
- Reference
- 6/2023/0336/HOUSE
- Jul 2014ExtensionOutlineIn report
Extension: Rear of property
Certificate of lawfulness for proposed single storey rear extension, insertion of rear dormer and replacement garage
- Documents
- 8 docs on file
- Reference
- N6/2014/0983/LUP
We flagged 1 thing worth checking at 10 Harmer Green Lane
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
30-day money-back guarantee
Sales history & valuation
Sale price has at least doubled since 2009.
£820,000
Modelled from EPC, postcode comparables and a sale-price growth of 6.4% per year over 13 years.
£800,000
Growth on file: 6.4% per year over 13 years.
Sales timeline
16 October 2022Most recent
£800,000
+128.6%over 13 years16 July 2009
£350,000
Median price across the last 5 sales in AL6 0AX: £480,000 (2024–2003).
Everything we know about 10 Harmer Green Lane, 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
On price per m², 10 Harmer Green Lane stands well clear of the street.
Price per m²
£7,547
Street avg £5,791
Floor Area
106 m²
Street avg 97 m²
Habitable Rooms
5 rooms
Street avg 5 rooms
CO₂ Emissions
4.9 t/year
Street avg 6.0 t/year
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
0.0 km
Welwyn North Railway Station — bus stop.
Closest school
0.5 km
St John's CofE Primary School. 15 schools nearby.
Go deeper on the local area
The full report breaks down crime, transport links, schools and air quality in depth.