Who to hire for a house that needs underpinning

Short answer

A structural engineer first, then a builder or a specialist underpinning or restumping contractor working to the engineer's design. Do not accept a quote from anyone who has not seen a level survey — 'we can underpin that' without measurement is a sales position rather than a diagnosis.

Plan itThere is time to get more than one quote, which is where the money is.

When it is someone else

Calling the wrong trade costs an attendance fee to be told so. These are the cases where this problem belongs to someone other than a Builder.

  • a structural engineer

    always, and first. The engineer specifies what is needed; the contractor executes it. Reversing that order is how people buy more underpinning than the house required.

  • a plumber

    a drain or water service leak is suspected as the cause. Fixing the house without fixing the water is temporary.

What to do before anyone arrives

  1. Get a floor level survey. It is a straightforward measurement and it turns opinions into millimetres.
  2. Collect your crack monitoring — dated photographs over months are worth a great deal here.
  3. Check whether your insurance covers any part of it. Many policies exclude gradual movement and cover damage from a specific escape of water, which is exactly why the cause matters.
  4. Find the site drainage: downpipes, surface falls, the garden beds against the wall.

What to ask when you book

  • Whose engineering design are you building to, and can I see it?
  • Is this underpinning, restumping or reblocking, and why is that the right answer for this construction?
  • How is the work sequenced and how long is the house occupied during it?
  • What contract and warranty insurance applies at this value in this state?

What changes the price

No dollar figures here: this directory holds no price data and an invented range is worse than none. What follows is what makes one of these jobs cost more than the same job next door, which is the part you can actually use when comparing quotes.

  • Number and depth of piers or stumps.
  • Access — a house with a crawl space is very different from one on a slab.
  • Whether the movement is still active, which changes the engineering.
  • Making good: cracks, doors, windows and floors after the structure is corrected.

Is this licensed work?

Structural building work, licensed in every state, generally requiring a written contract and statutory warranty insurance above a threshold. The engineering design is a registered professional's work.

There is no national register. Search the licence number with the regulator for the state the work is happening in.

Licensing thresholds and certificate requirements differ by state and change with amending regulation, so this page describes the mechanism rather than quoting a figure. The regulator’s own page is the current answer.

Common questions

Who should I hire for a house that needs underpinning
A structural engineer first, then a builder or a specialist underpinning or restumping contractor working to the engineer's design. Do not accept a quote from anyone who has not seen a level survey — 'we can underpin that' without measurement is a sales position rather than a diagnosis.
What is the difference between underpinning and restumping?
Restumping — also called reblocking — replaces the stumps a timber-framed house sits on and applies to houses with a subfloor. Underpinning extends and strengthens existing footings, usually on a slab or strip-footed house, by taking the load down to more stable ground. They solve similar symptoms on completely different construction, which is why a contractor should be naming your construction type before naming a method.
Should I fix the cracks first?
No. Repairing the cosmetic damage before the movement is stopped guarantees doing it twice, and it also destroys the record of how far things have moved. Fix the cause, allow the house to settle, then make good.

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Who to hire for

General information about who does what, not advice about your specific job. Licensing, consumer law and council rules differ by state and change; the regulator for your state is the current source. More guides to hiring a tradesperson.