Our Data Sources
18, Mardley Avenue, Welwyn has 21 entries in the Land Registry , most recently in August 2017 and a single entry in the EPC database dated February 2017.
We combine this information with that of neighbouring properties to estimate the property attributes and values.
The local information is scored as 1 out of 5 and is considered of low accuracy.
Price Range & Condition
Decorative condition can have a big effect on a property's value and this effect varies depending on the type, size and location of the property.
If 18, Mardley Avenue, Welwyn is in very good condition we estimate a sale value of £935,270 and a rental value of £3,522 per month.
However, if the property needs a lot of cosmetic work we estimate a sale value of £828,382 and a rental value of £3,120 per month.
Plot Size
According to data from HM Land Registry, 18, Mardley Avenue, Welwyn sits on a plot of 816 m2.
We have plot size data on 12 out of 13 other houses in the postcode and 18, Mardley Avenue, Welwyn sits on the 6th largest plot.
Energy Efficiency
18, Mardley Avenue, Welwyn has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 23 Feb 2017.
The property is connected to mains gas and has fully double glazed windows. It is heated using Boiler and radiators, mains gas.
Sold Prices
According to HM Land Registry, 18, Mardley Avenue, Welwyn was last sold on 8th August 2017 for £665,000 and was recorded as a freehold house.
The property has had 2 sales since 1995.
Since August 2017, the market for similar properties has risen by 37.2%.
- Sold Aug 2017£665,000
- Sold Dec 2005£355,000
Similar Properties Sold Nearby
According to the Land Registry and our network of Estate Agents, there have been 81 sales of properties similar to 18, Mardley Avenue, Welwyn within a radius of 1.3 kilometres over the last 2 years.
The most recent example is 15, Marlborough Close, Welwyn, AL6 0UG, a freehold house which sold for £1,150,000 on the 30th January 2026.
Read more about house prices in AL6.
- Sold Jan 2026£1,150,000 | 5 Bed House15, Marlborough Close, Welwyn, AL6 0UG15, Marlborough Close, Welwyn, AL6 0UG
- Sold Oct 2025£827,500 | 5 Bed House39, Robbery Bottom Lane, Welwyn, AL6 0UL39, Robbery Bottom Lane, Welwyn, AL6 0UL
- Sold May 2025£675,000 | 5 Bed House16, Marlborough Close, Welwyn, AL6 0UG16, Marlborough Close, Welwyn, AL6 0UG
•Nearby is defined as the radius comprising the nearest 2,000 addresses.
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Location Comparison
Mardley Avenue, Welwyn, AL6 has a total of 30 addresses. According to our analysis of all the public data, 18, Mardley Avenue, Welwyn is the 3rd largest and the 7th most expensive property on the street.
When compared to the postcode district it is £90k more expensive than the average property in AL6.
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Schools Nearby
- St Michael's Woolmer Green CofE VA Primary School700 m away
- Oaklands Primary School800 m away
- All Saints Church of England Voluntary Aided Primary School, Datchworth2.1 km away
- Monk's Walk School3.3 km away
- Ridgeway Academy4.9 km away
- Barnwell School5.0 km away
More reading links
Public Transport Nearby
- Knebworth|2.4 km away
- Welwyn North|2.5 km away
- Watton-at-Stone|4.8 km away
Available Internet Speeds
According to recent data from Ofcom, Superfast Broadband is available in this area.
According to recent data from Ofcom, Superfast Broadband is available in the area.
Risk of Flooding
According to data from the Environment Agency, the flood risk in this area is considered to be Very Low.
