Dead load
Dead load is the permanent self-weight of a building (roof, walls, floors, finishes, fixed services), a core AS/NZS 1170.1 action combined with live and wind loads.
Ask Chalkline about this →Dead load is the permanent (self-weight) load of the building itself: the roof, walls, floors, finishes, and fixed services. It is one of the core design actions under AS/NZS 1170.1 that the engineer combines with live and wind loads to size structural members.
The defining feature is that a dead load is permanent and fixed: it does not change with use, and it acts in the same place all the time. It is the weight of:
- the structure (framing, slabs, beams),
- the cladding, roofing, and linings,
- permanent finishes (tiles, screeds, render), and
- fixed services (ducts, pipes, hot-water units that stay put).
That is the difference from a live load, which is variable and depends on use (people, furniture, stored goods). Heavy fixed items, a green roof, a stone benchtop, a slab topping, are dead load and have to be allowed for, which is why a late change like “we’ll tile the whole roof terrace” or “swap to a concrete tile roof” can matter structurally.
For a builder the practical point is that the engineer’s design assumes a particular dead load, so do not add permanent weight the design did not allow for. Substituting a heavier roof, adding a screed or topping, or hanging fixed plant off the structure changes the dead load and can overload members or footings. If a permanent material gets heavier than documented, flag it to the engineer rather than assuming there is spare capacity.
Also known as: Permanent load, self-weight.
Category: Structure / Loads.
Related
See also
References
- AS/NZS 1170.1 Structural design actions, Standards Australia (verified 2026-06-01)
Last updated: 2026-06-01. Verified: 2026-06-01. Quarterly review for currency.