Nos. 18 & 20 Lon Isa is a Grade II listed building in the Cardiff local planning authority area, Wales. First listed on 30 November 2001. House.

Nos. 18 & 20 Lon Isa

WRENN ID
secret-storey-owl
Grade
II
Local Planning Authority
Cardiff
Constituency
Cardiff North MP: Anna McMorrin (Lab)
Country
Wales
Date first listed
30 November 2001
Type
House
Address
Nos. 18 & 20 Lon Isa, Rhiwbina Garden Village (N), Rhiwbina
OS grid reference
ST 158 811
Coordinates
51.52308, -3.21471
Source
Cadw listing

Also on this page: flood risk · radon risk · weather exposure · detailed attributes ↓

Description

Nos. 18 and 20 Lon Isa are a pair of semi-detached houses dating from the 19th century. They are two storeys tall and feature a smooth render exterior with a slate roof that has a central chimney. The houses have replacement glazing. At the centre, there are two prominent gables, each with a 3-light window on the upper floor and a 2-light window on the ground floor. The outer bays have shallow 3-light windows set at the eaves. The doorways are located in the angles with the advanced bay, with the original doorway preserved only at No. 18.

Local climate

Nos. 18 & 20 Lon Isa sits in a wetter-than-average part of the UK, with an average of 1,080 mm of rain a year. This makes it wetter than 86% of listed buildings in the UK. Its exposure to wind-driven rain is greater than that of 87% of listed buildings.

It experiences an average of 22 freeze-thaw cycles a year, fewer than 77% of listed buildings. Of these, 8 follow at least 1 mm of rain in the preceding 48 hours. Average temperatures at this location have risen by 0.3°C per decade since 1991.

Averages for 1991–2020; temperature trend 1991–2025. Figures describe the wider area (a grid cell of roughly 10 km), not the individual site. Contains modified Copernicus Climate Change Service information 2026.

More on this building

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Nearby listed buildings

  1. Nos. 14 & 16 Lon Isa Grade II 16 m
  2. Nos. 24 & 26 Lon-y-dail Grade II 22 m
  3. Nos. 17 & 19 Lon Isa Grade II 33 m
  4. Nos. 20 & 22 Lon-y-dail Grade II 33 m
  5. Nos. 10 & 12 Lon Isa Grade II 33 m
  6. Nos. 21 & 23 Lon Isa Grade II 37 m
  7. Nos. 13 & 15 Lon Isa Grade II 38 m
  8. Nos. 9 & 11 Lon Isa Grade II 47 m
  9. Nos. 5 & 6 Y Groes Grade II 47 m
  10. Nos. 6 & 8 Lon Isa Grade II 48 m