Llwyn Onn is a Grade II listed building in the Powys local planning authority area, Wales. First listed on 2 March 2004. House.
Llwyn Onn
- WRENN ID
- scattered-cupola-plover
- Grade
- II
- Local Planning Authority
- Powys
- Constituency
- Montgomeryshire and Glyndwr MP: Steve Witherden (Lab)
- Country
- Wales
- Date first listed
- 2 March 2004
- Type
- House
- Address
- Llwyn Onn, Llansantffraid-Ym-Mechain Village, Llansantffraid, SY22 6AH
- OS grid reference
- SJ 219 204
- Coordinates
- 52.77559, -3.15865
- Source
- Cadw listing
Description
Llwyn Onn is a three-storey house, part of a pair with Glanaber, which features a slightly irregular arrangement of five windows. The exterior is constructed of white-painted Flemish bond brickwork, with openings that have rubbed brick flat arches and stone sills. The top storey has 8-pane horizontally sliding sash windows, although the middle window of Llwyn Onn is a sham. The first and ground storeys have 16-pane windows of the hornless sash type. The entrance includes doors with a slate-roofed porch and canopy. Notably, the brickwork of Llwyn Onn appears more weathered and irregular compared to that of Glanaber. The interior has not been seen.
Local climate
Llwyn Onn receives an average of 890 mm of rain a year. This makes it wetter than 66% of listed buildings in the UK. Its exposure to wind-driven rain is lower than that of 56% of listed buildings.
It experiences an average of 43 freeze-thaw cycles a year, more than 84% of listed buildings. Of these, 24 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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- No EPC on record for this property
- Sale history — 3 transactions since 1997
- No related consent applications matched
- Detailed attributes — period, style, materials, features
- Flood risk assessment
- Radon risk assessment
- Weather exposure and heating demand — rain and frost month by month and year by year, wind direction, solar and humidity
Matched applications, energy data and sale records are assembled automatically and may contain errors. Flag incorrect data.
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