Description

Level threshold access to a home can provide an appealing indoor/outdoor flow and accessibility for all, but how do you achieve this while ensuring weathertightness?

Level entry from free-draining timber decks was possible with minimal risk of water ingress into the interior, and the principles remain to this day. NZS 3604:2011 Timber-framed buildings, and later E2/AS1 paragraph 7.1.1, indicated how we could safely design and build this junction.

As residential dwellings transitioned to reinforced concrete slab-on-ground construction, the difference between external ground level and internal finished floor level decreased markedly. Currently, the general NZS 3604:2011-stipulated minima are 150 mm above permanent paving or 225 mm above unpaved ground. Many of the adjacent outdoor living spaces became concrete patios, sometimes tiled, instead of suspended timber decks.

Scope

This article includes:

• Weathertightness with level access
• Achieving minimum clearances
  • Nib wall around perimeter of floor slab
  • Nib wall in separate pour
  • Other options
• Detail that needs robust design
• What do you do? Let us know