21 Northumberland Avenue, Dún Laoghaire, Co Dublin
Demolition of a two-storey rear return to build a new part-single, part-double storey extension.
D18B/0177 · Dun Laoghaire Rathdown County Council · Lodged 17 April 2018
- Reference
- D18B/0177
- Authority
- Dun Laoghaire Rathdown County Council
- Register status
- Decided
- Type
- Permission
- Received
- 17 April 2018
Summary
AI-generatedThe application for 21 Northumberland Avenue seeks permission to demolish a 34 sq.m two-storey rear return and replace it with a new 50 sq.m extension of part-single, part-double storey height. The works also include internal modifications, window alterations, new roof lights, and full refurbishment.
- Floor area
- 50 m²
Generated from the description above by an AI model and may contain mistakes. The council’s description is the authoritative record.
Official record
Development description
Permission for demolition of rear 2 storey return (ca 34 sqm) and replacement with a single storey extension (ca 50 sqm) part single part double storey height. Some internal modifications and modification to rear west facing first floor window. New roof lights to rear main roof and extension. Full refurbishment and associated landscaping and site works.
Land-use zoning
What this land is zoned for
“A To provide residential development and improve residential amenity while protecting the existing residential amenities”
Objective set by the COUNTY DEVELOPMENT PLAN 2022-2028 (2022–2028). The planning authority decides each application on its own merits — this is the zoning context, not a compliance assessment.
Read the zoning objectives in the development planBuilt & sold
What happened next
Beyond the decision: whether this development was built, and what property here has sold for.
Recent sales nearby
within 500 m| Address | Date | Price | Distance |
|---|---|---|---|
| 34 Northumberland Avenue, Dunlaoughaira, Co Dublin | Dec 2025 | €1,900,000 | 60 m |
| 15 Northumberland Ave, Dun Laoghaire, Dublin | May 2025 | €1,250,000 | 77 m |
| 32 Mulgrave St, Dun Laoghaire, Dublin | Jul 2025 | €880,000 | 82 m |
| 30 Mulgrave St, Dun Laoghaire, Dublin | Nov 2025 | €1,800,000 | 97 m |
| 3 Patrick Court, Patrick St, Dun Laoghaire | Jun 2026 | €585,000 | 103 m |
| 2 Patrick Court, Patrick St, Dun Laoghaire | Apr 2026 | €572,000 | 104 m |
| 21 Mulgrave Terrace, Dun Laoghaire, Dublin | Jul 2025 | €1,400,000 | 106 m |
| The Coach House, Sydenham Mews, Corrig Avenue | Jan 2026 | €750,000 | 149 m |
Nearby properties, not this site — a guide to local values.
Sources: Building Control Management System (commencement notices) and the Residential Property Price Register, licensed under CC BY 4.0. Records are matched to this application by location and may not be exhaustive; always confirm against the official source before relying on them.
Key dates
Timeline
- Application received17 April 2018
- Decision issued11 June 2018
In the area
Applications near this site
Other planning applications within about 500 m — what else is being proposed or built nearby.
- Granted40 m away
Planning permission for — Demolition of existing flat roof extension to rear at Basement level
18, Northumberland Avenue, Dun Laoghaire, Dublin, A96K793
D24A/0551/WEBDún Laoghaire–RathdownLodged 24 Jul 2024Extension
- Granted40 m away
The development will consist of: Alterations to the proposed development permitted under Register Reference…
18, Northumberland Avenue, Dun Laoghaire, Dublin, A96K793
D26A/0155/WEBDún Laoghaire–RathdownLodged 1 Mar 2026Extension
- Granted40 m away
The development will consist of the moving and widening of the existing vehicular entrance. This will include…
31, Northumberland Avenue, Dun Laoghaire, Co. Dublin, A96EY19
D25A/0110/WEBDún Laoghaire–RathdownLodged 14 Feb 2025Infrastructure
- Granted50 m away
Permisson for development. Demolition of existing one & two-storey rear extensions to three story mid-terrace…
31 Northumberland Avenue, Dun Laoghaire, Co. Dublin, A96EY19
D23A/0166Dún Laoghaire–RathdownLodged 13 Mar 2023Extension
- Granted50 m away
Redevelopment from existing seven residential units to five apartments with associated car parking to front…
33 Northumberland Avenue, Dun Laoghaire, Co. Dublin.
D02A/0146Dún Laoghaire–RathdownLodged 17 May 2002Apartments
- Granted60 m away
The development will consist of alterations to the previously granted permission D23B/0521 with a reduced…
34, Northumberland Ave, Dun Laoghaire, A96Y7H1
D26B/0256/WEBDún Laoghaire–RathdownLodged 27 Apr 2026Alterations
- Granted60 m away
(1) Removal of part of existing railings to Northumberland Avenue to provide vehicular access. (2) Provision…
34, Northumberland Avenue, Dun Laoghaire, Co. Dublin.
D04A/0641Dún Laoghaire–RathdownLodged 10 Jun 2004Alterations
- Granted60 m away
Demolition of existing two-storey extension to the rear (east) and one storey boiler room to the side…
34, Northumberland Avenue, Dun Laoghaire, Dublin, A96Y7H1
D23B/0521Dún Laoghaire–RathdownLodged 14 Nov 2023Extension
Related developments
Similar applications
Ranked by what these developments actually propose, not by matching words — so you can see how comparable applications were decided.
- RefusedExtension
Permission for the demolition of a single-storey extension to the rear and alterations of pitched roof to…
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D19B/0153Dún Laoghaire–RathdownLodged 27 Mar 2019
- GrantedExtension
Permission for demolition of single storey rear return and construction of part single storey part two storey…
17, Finglas Road, Dublin 11
WEB5194/21Dublin CityLodged 13 Dec 2021
- GrantedExtension
Permission for demolition of existing single storey rear extension and construction of new single storey rear…
83, Saint Magdalen Terrace, Dublin 4
5078/22Dublin CityLodged 20 Oct 2022
- GrantedExtension
Permission for; Demolition and alteration of existing single storey extension to side and rear; Construction…
23 Grange Wood, Rathfarnham, Dublin 16
D19B/0063Dún Laoghaire–RathdownLodged 11 Feb 2019
- GrantedExtension
Permission for the demolition of the existing single storey extension and partial demolition of the existing…
Grevisk, 5 Saint Joseph's Terrace, Tivoli Road, Dun Laoghaire, Dublin, A96F500
D24A/0211Dún Laoghaire–RathdownLodged 2 Apr 2024
- GrantedExtension
Permission for the demolition of existing two-storey and single-storey extensions to rear and the…
4, Rugby Road, Ranelagh, Dublin 6, D06 XD27
WEB1030/24Dublin CityLodged 12 Jan 2024
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