French Door Installation in Ireland: What Is Actually Involved

French doors are one of the most frequently requested joinery commissions for homeowners across Co. Louth and South Armagh, particularly in properties that have been extended toward a rear garden or that have a south or west-facing wall that could benefit from more light and access.

What the installation actually involves is worth understanding before you begin the project. There are structural questions, opening-size questions, and material questions that need to be answered before a carpenter measures up, and getting them right at the start saves significant cost and disruption later.

First Question: Is the Opening Structural?

Before any French door installation can be planned, the wall the doors will go into needs to be understood.

Cavity wall construction (the most common in Irish homes built from the 1960s onward) has a concrete or block outer leaf, a cavity, and a block inner leaf. An opening in this wall requires a lintel over the opening to carry the load of the wall above it. For a French door opening, which is typically 1,600mm to 2,400mm wide, the lintel size must be specified correctly. This is structural engineering, and in most cases a builder or structural engineer needs to confirm the lintel specification before the opening is created.

Solid wall construction (found in older properties across Carlingford and throughout Co. Louth, including stone-built houses) requires careful assessment. The wall carries load differently from cavity construction and the opening creation must be designed and supervised appropriately.

John creates French door openings in existing walls as part of the commission where the brief requires it. He works with the client’s structural engineer or builder to ensure the opening is correctly prepared before the doors are measured and made.

For properties where a sliding door or a rear extension already has an opening of appropriate size, the structural question is already answered and the project is a straightforward replacement.

Second Question: What Size Opening?

French doors come in a limited range of standard manufactured sizes, typically centred on 1,200mm, 1,500mm, 1,800mm, and 2,100mm wide pairs. Bespoke French doors can be made to any width within the structural limits of the opening.

The practical sizing considerations:

  • Two leaf French doors (the traditional configuration) work best between 1,200mm and 1,800mm wide. Wider than this and each leaf becomes heavy and the door can sag on its hinges over time
  • For openings wider than 1,800mm, a three-leaf configuration with a fixed centre panel, or bifold doors, may be more appropriate
  • Height is typically dictated by the existing or new opening. Standard door height is 2,100mm. Full-height doors to the ceiling line are possible in properties with appropriate ceiling height and are increasingly popular in open-plan renovations

The opening size should be agreed before any door is made. John confirms the exact clear opening dimensions at the site visit, accounting for the frame thickness and any threshold depth.

Third Question: Timber or Bifold?

The choice between traditional French doors and bifold doors is a functional one as much as an aesthetic one.

French doors open inward or outward on hinges. They provide a full-width opening when both leaves are open. They are mechanically simple, long-lasting, and can be made in solid hardwood to the same standard as any other joinery in the house. The limitation is that both leaves need to be opened to create the full-width access, and each leaf needs space to swing.

Bifold doors fold and stack to one side when opened, creating a wider usable opening from the same structural frame. They suit larger openings where the French door configuration would require swinging doors into the room or garden significantly. Bifold hardware is more complex than French door hardware and requires more maintenance over the long term. At the quality end, bifold doors in timber are excellent. At the budget end, they are a source of ongoing problems.

For most domestic openings in Co. Louth homes where the new opening is 1,200mm to 1,800mm wide, French doors in solid hardwood are the more durable and lower-maintenance choice.

What the Installation Sequence Looks Like

Once the opening is confirmed, the structural work is complete, and the doors are made, installation proceeds as follows:

Frame installation: The door frame is installed first. It must be plumb, square, and true to the opening, because every error in the frame is carried into the door hang. For a stone-wall opening as found in many Carlingford properties, the frame is bedded and secured carefully to accommodate the irregular reveals.

Sill and threshold: An external French door installation requires a properly specified sill and threshold, sealed against weather ingress from below. This is a common point of failure in lower-quality installations and it is worth specifying clearly.

Door hanging: Each door leaf is hung in turn, adjusted for an even gap around the frame, and checked for correct swing and closure. The stile rebate where the two leaves meet must close cleanly for the doors to seal properly.

Glazing: Where the doors have not been factory-glazed (some bespoke doors are glazed in the workshop; others are glazed on site), the sealed double-glazed units are fitted into the prepared rebates and sealed with appropriate flexible sealant.

Hardware and ironmongery: Multi-point locking hardware on both leaves, espagnolette bolts at top and bottom of the inactive leaf, handles, and hinges are fitted and adjusted.

Weather seals: Compression seals are fitted at the frame head and jambs, threshold seal at the base. The installation is tested for draught and weather performance before completion.

A typical French door set installation takes one to two days. Stone wall or heritage property installations take longer.

What This Costs

For bespoke solid oak French doors in the Co. Louth and South Armagh market in 2026, realistic supply-make-and-fit costs:

  • Standard two-leaf set, 1,500mm opening: €3,500 to €5,000
  • Wider set or with sidelights, 1,800-2,100mm: €5,000 to €7,000
  • Opening creation in an existing wall: typically €800 to €2,500 as a separate trade, depending on wall construction

The full door cost guide covers the pricing for all door types.

Frequently Asked Questions

Do French doors require planning permission? In most cases, no. Fitting French doors into an existing opening or creating a new opening in the rear wall of a house falls within permitted development rights in Ireland for most residential properties. Exceptions apply for certain protected structures, listed buildings, and some estate management schemes. John will flag this at the site visit if it appears relevant.

Inward or outward opening? Both are viable. Outward opening leaves are better in a restricted interior space because they do not swing into the room. Inward opening is more secure against wind loading in exposed positions. For most Irish garden-facing French doors, outward opening is the more practical choice.

What glass specification for a French door? Double-glazed sealed units with a low-emissivity coating and argon gas fill are the standard specification for Irish conditions, meeting the minimum thermal performance requirements for building regulations. Triple glazing is an option for highly exposed or thermally demanding situations but adds significant weight to each leaf.

For French doors or bespoke hardwood door commissions in Dundalk, Carlingford, Newry, or across Co. Louth, the Setanta doors and windows service starts with a site visit. Call John on 083 003 3268 to discuss your project.