SiteRep

Do I need planning permission for a modular home in Ireland?

Yes, in almost all cases. A modular home used as a dwelling is assessed as a house regardless of its factory-built construction method, so it needs full planning permission unless it genuinely falls within the very limited 25 m² non-habitable outbuilding exemption.

The Planning and Development Regulations 2001 assess a structure by its use and effect, not by its method of construction, so a factory-built modular or prefabricated unit intended for use as a home is treated in exactly the same way as a traditionally built house for planning purposes.

This means a modular home used as a dwelling — whether as a main residence or as a second home for a family member — requires a full planning application in almost every case, addressing the same matters as a conventional house: siting, design, wastewater treatment, access, and compliance with the local development plan's policies on rural or residential development.

The 25 m² domestic outbuilding exemption in Class 2 of Schedule 2 does not cover a modular unit fitted out with sleeping and living accommodation, since that exemption expressly excludes structures used for human habitation, regardless of floor area or the fact that it may look similar to a garden cabin.

What a modular home planning application needs to address

Expect to cover the following, as with any new dwelling:

  • Compliance with the local authority's development plan zoning and rural housing policy
  • A satisfactory wastewater treatment solution if not connected to a public sewer
  • Safe vehicular access and sightlines from the public road
  • Siting, scale and design that respect the character of the area
  • Whether the site qualifies under any local needs or rural housing criteria that apply in that county
  • Compliance with Building Regulations for the specific modular construction system used

Manufacturers who market modular homes as "exempt" or requiring "no planning permission" are almost always describing the position in a different jurisdiction or referring only to a non-habitable garden building, not a house — this claim should always be independently verified with your own local authority.

Placing one temporarily

Even a modular unit intended as temporary accommodation while a house is being built or renovated on the same site generally still needs planning permission for a temporary dwelling, subject to conditions requiring its removal once the main house is complete.

Sources

Last reviewed 20 August 2026. General information only — not legal or planning advice.

Related questions

← Back to all questions