Observation pack · South Dublin County Council

23 Knocklyon Grove, Knocklyon, Dublin 16, D16 Y443

Single storey extension, a rear attic dormer extension, 3 no. roof windows to front elevation, alterations to existing roof height and all elevations.

Observations close 18 Nov 2026 13 days left

5 weeks from receipt (received 14 Oct 2026) · s.34 Planning and Development Act 2000 · art. 29 Regulations 2001 · fee €20 · council decision due 8 Dec 2026

The application

Reference: SD26B/0466W · full record
Authority: South Dublin County Council
Type: Permission
Status: Valid
Applicant: not published by the national dataset — see the council register
Units: —
Floor area: 103 m²
Site area: 507 m²
Received: 14 Oct 2026
We first saw it: 28 Oct 2026, 01:34
Decision due: 8 Dec 2026
Decision: not yet decided

The national dataset truncates descriptions (80 characters for DLR, 70 for Fingal) and omits the applicant. The full description and the drawings are on the council register linked in step 1.

How to submit an observation

Read the file on the council register.Drawings, planning statement and site notices are at https://planning.agileapplications.ie/southdublin/application-details/71214.
Write your observation.Quote SD26B/0466W at the top, give your name and the address the authority should reply to, and confine it to planning matters — zoning objective, height, overlooking, traffic, drainage, heritage. What you say here is what you can later appeal on.
Pay the €20 fee.Every submission needs it; without it the observation is invalid and is returned. South Dublin County Council takes it online with the submission or at the counter.
Submit before 18 Nov 2026.Online through the register above, or in writing to the Planning Department, South Dublin County Council. The test is the date the authority receives it, not the date you post it.
Keep the acknowledgement.The council's receipt is your proof of a valid observation — see below.

Statutory basis. Section 34(1) of the Planning and Development Act 2000 (as amended) requires a planning authority to consider any submission or observation made to it in accordance with the Regulations. Article 29 of the Planning and Development Regulations 2001 (as amended) sets the window: a submission or observation must be received by the authority within five weeks beginning on the date of receipt of the application, and must be accompanied by the prescribed fee of €20. A submission received after the window, or without the fee, is invalid and the authority must return it.

After you submit: keep the acknowledgement. Under the 2024 Act it secures your right to appeal — only the applicant and a person who made a valid observation may bring the council's decision to An Coimisiún Pleanála, within four weeks of the decision. Making a valid observation is also what buys a right of appeal: under s.37(1) of the 2000 Act, only the applicant and a person who made a valid submission or observation to the planning authority may appeal the decision to An Coimisiún Pleanála (within four weeks of the decision). Missing the five-week window closes both doors.

What the site is zoned

Code	Objective	Plan	In force
G1 Open space with recreation	OS: To preserve and provide for open space and recreational amenities	south dublin county development plan 2022 2028	8 Mar 2022 → 8 Mar 2028
R2 Existing residential	RES: To protect and/or improve residential amenity	south dublin county development plan 2022 2028	8 Mar 2022 → 8 Mar 2028

An application that accords with the zoning objective is hard to resist on principle; one that does not may be a material contravention, which the council can only grant by the s.34(6) procedure with its own notice and window.

Source: South Dublin County Council development plan zoning · fetched 11 Sept 2026, 23:18

Source	Licence	Fetched	Link
South Dublin County Council development plan zoning	—	11 Sept 2026, 23:18	open

Designations on or near the site

Radon risk area × 1
About 1 in 20 homes in this area is likely to have high radon levels

Nearby precedents within 500 m, last 5 years

Decisions

Reference	Decision	Decided	Units	Distance	Description
SD26A/0197W	Request additional information	9 Oct 2026	—	488 m	The proposed development will consist of the subdivision of the existing rear garden space, to enable the erection of 2no. single storey, 3-bed, detached dwellings; access to the development will be provided via a new roadway, from Knocklyon Rd; and, all associated site works, including landscaping, boundary walls and treatments, Suds drainage, to facilitate the development.
ED26/0098	Declared exempt	2 Oct 2026	—	276 m	Rear extension c22m, front door to be brought forward to existing porch door. Building up right-hand side (if facing) of garage in similar brick finish to existing house to narrow the garage door opening.
SD26B/0372W	Request additional information	30 Sept 2026	—	355 m	Retention for a flat roof over the existing front porch extension; revised ground floor front elevation fenestration; revised first floor side elevation fenestration.
SD26A/0182W	Refuse permission	17 Sept 2026	5	449 m	Construction of 5 no. 2-storey 4-bed detached dwellings; New internal access road and widening of the existing vehicular access from The Rookery; New boundary and entrance gates to Mount Michael House; Car parking, bin stores, landscaped communal open space and boundary treatments; All associated site works and services; The lands are adjacent to Mount Michael House, a Protected Structure.
ED26/0081	Declared exempt	7 Sept 2026	—	164 m	Replacing one car park space with one bike rack for bicycles to be parked for visitors to the Iona Centre. Improving accessibility and encouraging cyclists to come to the centre.
SD26A/0156W	Grant permission for retention	19 Aug 2026	—	487 m	The retention of 1.96m wide pedestrian entrance, disabled ramp, handrail, balustrading and associated site works.
SD26B/0309W	Grant permission	17 Aug 2026	—	100 m	Construction of a 32sq.m ground floor flat roof extension to the rear, providing a new utility room, extended kitchen and dining room with no.1 new rooflight; Attic conversion to the rear extending the property to two storeys to include two additional bedrooms, office space, shower room and en-suite; Two roof lights to the north facing front elevation; External insulation with brick finish to the front, side and rear facades; Ancillary site works as required to facilitate construction works.
SD26B/0225W	Grant permission for retention	6 Jul 2026	—	114 m	The development consists of re-location and enlargement of ground floor window to eastern side elevation of dwelling-house.

Appeals

ACP case	Type	Outcome	Decided	Distance
501266	Planning Appeal	Refused	25 Aug 2026	368 m
500186	Planning Appeal	Granted with conditions	8 Apr 2026	249 m
322307	Planning Appeal	Granted with conditions	6 Aug 2025	437 m
315930	Planning Appeal	Refused	14 Feb 2024	374 m
310999	Planning Appeal	Granted with conditions	17 Jan 2022	320 m

If neighbours here have appealed before and lost, the inspector's report on that case is the single most useful thing to read.

What has happened on this file

14 Oct 2026 New application · observations close 18 Nov 2026

Generated from the Planning Register store; nothing was fetched live for this page. Source: national planning dataset, fetched 28 Oct 2026, 01:34. Not legal advice — confirm the deadline with South Dublin County Council before relying on it.