Does a dormer need planning permission?

QBeing in lockdown has given us time to think about improvements we can make to our home. We live in a semi-detached house in Dublin and have already extended out the back so the house is just under 1,300sq ft. We are thinking of doing an attic conversion which will involve building higher than the gable wall, raising the roof and putting in dormer windows at the back to create extra space. We are also thinking of putting in dormer windows to the front of the house which will effectively give us an extra floor. There are plenty of attic conversions with dormer windows to the rear in our estate but none to the front. Would I have difficulty getting planning permission to do this and is there anything else I should consider?

AIn recent years we have become accustomed to reading about a housing shortage in Ireland together with debates about reasons for the shortage and action that should be taken to mitigate it. Under these circumstances it makes perfect sense for homeowners to look at accommodation they already inhabit and investigate ways in which smart design might be used to expand or improve it in response to their needs and aspirations.

One popular way of utilising untapped potential in existing houses is the conversion of attics to habitable space. Compliance with Building Regulations is crucial when creating habitable rooms and the Department of Housing, Planning and Local Government advises that it is good practice for such rooms to have a minimum ceiling height of 2.4m, while also providing technical guidance about heights of attic rooms in particular.

Thus the addition of dormer structures is frequently necessary for attic conversions to be regarded as properly habitable as well as spatially and economically viable.

Some homeowners who would like to transform their attics find it difficult to decide upon the exact scope of conversion due to concern about controversy that a new dormer might cause and how their planning authority might respond to design proposals when the requisite planning permission is sought.

Factors that a planning authority will usually weigh up in relation dormers include potential overlooking and loss of daylight in neighbouring properties along with the visual impact of a new dormer in the context of the surrounding built environment.

With reference to the latter, applicants for planning permission are generally discouraged from proposing dormers on the rear roof of a house which is higher than the existing main roof ridge; although in some instances these can be permissible where dormers are set back behind the ridge so as to minimise visibility from the street. Cases like these are often decided on the basis of individual merit so careful design is important.

As for dormers on front roofs, a welldesigned dormer can enhance an existing house and add a new dimension to its appearance; there is, however, a balance to be struck between respecting the original character of a house and transforming it into something new and potentially at odds with neighbouring properties.

Registered architects frequently advise homeowners about appropriate design concerning attic conversions and dormers along with relevant aspects of the planning process and the best way to achieve the outcome they desire.

Planning authorities normally encourage engagement with them in pre-planning consultation before a formal application for permission is made.

Advice offered by planning authorities in this context is typically informal and, while it may not provide certainty in relation to the outcome of the planning process, where an authority does give clear pre-application guidance it is always prudent to heed it.

Research into previous applications for similar proposals nearby can also be informative and show not only how a planning authority reacted to similar previous designs but also whether there were any objections, how decisions were made and whether they were appealed to An Bord Pleanála.