HM Land Registry records the plot of land for 9, Knowle Drive, Harpenden as measuring 224 m².

That makes it the 8th largest plot in the postcode, where 32 of the 34 other houses have recorded plot data.

9, Knowle Drive, Harpenden has an Energy Performance Rating (EPC) of C. This is based on the most recent assessment, dated 23 Apr 2024.

The property is connected to mains gas and has fully double glazed windows. It is heated using a boiler and radiators (mains gas).

The most recent sale of 9, Knowle Drive, Harpenden completed on 28th June 2024 at £625,000 and was recorded by HM Land Registry as a freehold house.

Since 1995 the property has sold twice.

Values of comparable properties have risen by 27.2% over the period since June 2024.

• Sold Jun 2024£625,000
• Sold Jul 1996£90,000

Since 2017 206 properties similar to 9, Knowle Drive, Harpenden have sold within a radius of 600 metres, per the Land Registry and our network of Estate Agents.

The latest, on the 4th November 2025, was 6, Broadstone Road, Harpenden, AL5 1RG, a freehold house which sold for £625,000.

Read more about house prices in AL5.

• Sold Nov 2025£625,000 | 3 Bed House6, Broadstone Road, Harpenden, AL5 1RG6, Broadstone Road, Harpenden, AL5 1RG
• Sold Dec 2024£595,000 | 3 Bed House8, St. Michaels Close, Harpenden, AL5 1EW8, St. Michaels Close, Harpenden, AL5 1EW
• Sold Nov 2024£535,000 | 3 Bed House24, Broadstone Road, Harpenden, AL5 1RG24, Broadstone Road, Harpenden, AL5 1RG
• Sold Aug 2024£550,000 | 3 Bed House50, Knowle Drive, Harpenden, AL5 1RW50, Knowle Drive, Harpenden, AL5 1RW
• Sold Aug 2024£700,000 | 3 Bed House37, Coleswood Road, Harpenden, AL5 1EF37, Coleswood Road, Harpenden, AL5 1EF
• Sold Jul 2024£550,000 | 3 Bed House14, Tarrant Drive, Harpenden, AL5 1RP14, Tarrant Drive, Harpenden, AL5 1RP
• Sold Nov 2023£560,000 | 3 Bed House33, Tarrant Drive, Harpenden, AL5 1RP33, Tarrant Drive, Harpenden, AL5 1RP
• Sold Dec 2022£695,000 | 3 Bed House18, Tarrant Drive, Harpenden, AL5 1RP18, Tarrant Drive, Harpenden, AL5 1RP
• Sold Oct 2022£590,000 | 3 Bed House44, Knowle Drive, Harpenden, AL5 1RW44, Knowle Drive, Harpenden, AL5 1RW
• Sold May 2022£550,000 | 3 Bed House7, Kingcroft Road, Harpenden, AL5 1EH7, Kingcroft Road, Harpenden, AL5 1EH
• Sold Apr 2022£575,000 | 3 Bed House14, Broadstone Road, Harpenden, AL5 1RG14, Broadstone Road, Harpenden, AL5 1RG
• Sold Nov 2021£540,000 | 3 Bed House16, Knowle Drive, Harpenden, AL5 1RW16, Knowle Drive, Harpenden, AL5 1RW
• Sold Sep 2021£548,000 | 3 Bed House25, Tarrant Drive, Harpenden, AL5 1RP25, Tarrant Drive, Harpenden, AL5 1RP
• Sold Jun 2021£490,000 | 3 Bed House42, Knowle Drive, Harpenden, AL5 1RW42, Knowle Drive, Harpenden, AL5 1RW
• Sold Apr 2021£568,000 | 3 Bed House46, Coleswood Road, Harpenden, AL5 1EQ46, Coleswood Road, Harpenden, AL5 1EQ
• Sold Dec 2020£470,000 | 3 Bed House14, Knowle Drive, Harpenden, AL5 1RW14, Knowle Drive, Harpenden, AL5 1RW
• Sold Jul 2020£535,000 | 3 Bed House1, Tarrant Drive, Harpenden, AL5 1RP1, Tarrant Drive, Harpenden, AL5 1RP
• Sold Aug 2019£475,000 | 3 Bed House6, Tarrant Drive, Harpenden, AL5 1RP6, Tarrant Drive, Harpenden, AL5 1RP
• Sold Nov 2018£450,000 | 3 Bed House2, Knowle Drive, Harpenden, AL5 1RW2, Knowle Drive, Harpenden, AL5 1RW
• Sold Aug 2017£558,000 | 3 Bed House12, Tarrant Drive, Harpenden, AL5 1RP12, Tarrant Drive, Harpenden, AL5 1RP

Of the 34 addresses on Knowle Drive, Harpenden, AL5, 9, Knowle Drive, Harpenden comes out as the 29th largest and the 17th most expensive in our analysis of the public data.

It is also £394k less expensive than the average property across the AL5 district.

• The Grove Infant and Nursery School

  400 m away
• The Grove Junior School

  400 m away
• High Beeches Primary School

  1.0 km away

• Sir John Lawes School

  2.0 km away
• Katherine Warington School

  2.0 km away
• St George's School

  2.2 km away

• Harpenden

  |

  1.4 km away
• St Albans City

  |

  6.1 km away
• St Albans Abbey

  |

  6.7 km away

The flood risk here is rated Very Low, based on Environment Agency data.