Calculators

Rule-of-thumb, NZ-construction-accurate estimating tools — real materials lists and cutting plans, not just a square-metre guess.

Available now

Coming soon

Planned, not built yet — listed here so you know what's next.

Planned

Footings

Pad and strip footing size and depth from bearing load and ground conditions, NZS 3604 style — plus a concrete volume and bag-count materials list.

Footing sizeDepthConcrete volume
Planned

Piles

Timber pile size and spacing under a floor, from bearer spans and pile height — with a full pile and bearer materials list.

Pile spacingPile sizeBearers
Planned

Wall Framing

Stud spacing and sizing, dwangs, and a prenail-ready materials list for a wall frame — plus a rough erection time estimate, same as the retaining wall labour estimate.

StudsDwangsPrenailErection time
Planned

Lintels

Header beam sizing over door and window openings from span and roof load, off the NZS 3604 lintel tables.

Lintel sizeOpening span
Planned

Roof Framing

Rafter and ceiling joist spans and sizing off the NZS 3604 tables, with a full roof framing materials list.

RaftersCeiling joistsSpans
Planned

Bracing

Wall bracing demand vs. bracing-unit capacity, NZS 3604 style — check a floor plan actually stacks up before you frame it.

Bracing demandBU capacity
Planned

Stair Stringer

Rise/going/tread count for a code-compliant stringer between two levels, with a cut-list for the stringer itself.

Rise & goingCut list
Planned

Pergola / Carport

Post, beam, and rafter spacing and sizing for a simple open-roof structure, spanned to your dimensions.

PostsBeamsRafters
Planned

Paling Fence

Post spacing, rail count, and paling coverage for a standard timber paling fence — built on the same post/rail/infill engine as the retaining wall calculator.

PostsRailsPalings
Planned

Roof Cladding

Sheet count, purlin spacing, and flashing lengths for a simple gable or skillion roof.

Sheet countPurlinsFlashing
Planned

Guttering & Downpipes

Gutter length and downpipe count and fall, sized off your roof area and catchment.

Roof areaFallDownpipes