Building Regulations in Northern Ireland: Technical Booklet H

Northern Ireland regulates stairs and barriers through Technical Booklet H (2012), guidance to the Building Regulations (Northern Ireland). For a private house stair, the figures match England’s Approved Document K: 220 mm max rise, 220 mm min going, 2 m headroom, 900–1000 mm handrails, 900 mm guarding (1100 mm on external balconies), the 600 mm guarding trigger and the 100 mm gap.

One difference in how it’s written: Technical Booklet H doesn’t set a 42° maximum pitch the way England does. Instead it controls the slope by limiting rise and going together — the 2R + G rule, kept between 550 mm and 700 mm. The end result is a similar stair; you just size it by rise and going, not by a pitch angle.

For the shared numbers see the England stair & guarding rules.