Bifold Doors in Ireland — Cost, U-value, and When They're the Right Choice

Aluminium bifold door (3 m, 3 panels) in Ireland: €4,500–€8,500 installed. U-value 1.0–1.4 W/m²K for double-glazed; 0.9–1.2 for triple-glazed. Open-plan living — full opening when the doors fold back. Cheaper to operate on a large opening than a slider (each panel is lighter). Triple-glazed bifolds can hit BER A1. Most common in Irish self-builds on the south or west elevation. The opening size matters: a 3-panel bifold needs 3 m of clear wall; a 5-panel needs 5 m. Threshold detail: most Irish self-builds use a low threshold (15–25 mm step) for indoor-outdoor flow; a flush threshold (level with the inside floor) costs more but is best for accessibility.

TL;DR

• Aluminium bifold door (3 m, 3 panels) in Ireland: €4,500–€8,500 installed. U-value 1.0–1.4 W/m²K.

• Open-plan living — full opening when the doors fold back. Cheaper to operate on a large opening than a slider.

• Triple-glazed bifolds can hit BER A1 (U-value 0.9–1.2). Most common in Irish self-builds on the south or west elevation.

When this matters most

You're considering a bifold door for indoor-outdoor flow.

When this doesn't apply

You've already specified the door.

Frequently asked questions

How much do bifold doors cost in Ireland?

Aluminium bifold (3 m, 3 panels): €4,500–€8,500 installed. Triple-glazed: add €500–€1,500. 5-panel: €7,000–€14,000.

What is the U-value of a bifold door?

Double-glazed: 1.0–1.4 W/m²K. Triple-glazed: 0.9–1.2. Can hit BER A1 with the right frame and glazing.

Bifold or sliding door?

Bifold for full opening (panels fold back, indoor-outdoor). Slider for partial opening (one panel slides behind the other). Slider is warmer per m²; bifold is cheaper to operate on a large opening.

Sources

NSAI, I.S. EN ISO 10077. https://www.nsai.ie/