Calculating the cost of work

Calculating the cost of work

Calculating the estimated cost of work is challenging

When scheduling work in your LTMP, we need to estimate what that will likely cost because we need to help you budget for it. 

But estimating the cost of any building work isn't easy.  Especially in the current construction environment where every building contractor and subbie seems so busy they don't need your work. 

But estimating can be done and needs to be done.  So we have to find a way to be as accurate as possible.  It turns out that you have to spend some time on it.  And it helps if you have some experience and ways to find the base values of labour and materials. 


Most of our team have personally been finding contractors to work on their own properties.  That helps us understand how competitive the market is and how quotes and costs can vary greatly from one source to another.   

Also, the more plans we prepare and the more feedback we get, the more experienced we each become. 

Quantity Surveyor (QS) Tools

Our planners have access to the QS database QVCostbuilder.  Quantity Surveyors use This highly regarded website and database service to check the typical rates for building work, region by region.  QVCostbuilder is a subscription service, allowing the rates to be frequently updated.  However, in the current environment (mid-2023), we have seen huge increases in rates and prices for around two years and have become aware that we need to keep an open mind about the accuracy of the QVCostbuilder data and look for other sources for cross-checks.   

Our own rates and data

We also have our own rates and data, especially for those items where publicly available data is scarce.  Our planners are also quick to call their teammates when estimating work where they aren't confident and one or more others in the team have more recent experience.  We are also always looking for feedback on work that has been recently carried out.  That's why if you tell us you just had some work carried out, we will quickly ask, "How much did it cost". 


Our planners speak to specialist contractors often.  We don't hesitate to contact fire, HVAC, lift, door servicing and other specialist contractors to discuss the costs of work.  This has helped build our database of benchmark estimates, such as the cost of replacing a lift or a fire panel.  This relationship with contractors also helps us understand what to look for and the life of equipment. 

Online searches

We also use publicly available data online when looking for the cost of more obscure items we haven't had to estimate before.  Examples we have had are marina pontoons, low-light emitting outdoor pathway lamps and bolt-down speed bumps.  Fortunately, almost everything we need prices for is available online.


We regularly talk to building and painting contractors to keep abreast of the current labour rates.  But they vary from city to city, trade to trade and contractor to contractor.  Currently (mid 2023), we understand the rates to be between $65 per hour to $95 per hour depending on the skill required and the other factors already mentioned.  As an example, for painting work, we might start with $65 for a simple job requiring an entry-level brush hand and up to $95 for experienced abseiling painters. 


We have developed our own rates for scaffolding after talking to several scaffolding companies.  These are currently (mid-2023) a base of $20 per sq m of wall space for erecting and dismantling plus 8% per week for rent.  We increase the rate for complex setups (hilly suburbs, sloping ground, scaffolding over roofs etc.).

Then we double check

Then when we have made our calculations, we carry out a "reasonableness" test.  We ask ourselves, "Does this cost sound about right?".  


Calculating the estimated cost of work is challenging.  Because we are trying to predict what another person will want to be paid for the labour and the materials.  And the further out in time the job is likely to be carried out, the greater the error will likely be.

So we know we are likely to be wrong, but by including our rates and calculations in the plan, at least the total cost can be updated when more accurate information is available. 

And of course, we welcome feedback.  If someone knows better than we do, we are more than willing to listen. 

Updated 28 May 2023 JB




Last update 26 May 2023 JB

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The Plan Heaven team.

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