Using Square Meter Rates

Why Can’t You Give Me a Square Meter Rate?

As builders and renovation consultants, we are often asked to give an estimate using square meter rates.  It should be easy they say.  Yes, it would certainly save us a lot of time if we could just use square meter rates.  But the maths just don’t work out.

Let’s say someone says they want to renovate an area that is 100m2.  They also have a 9m2 bathroom they want tiled.  We’ll keep the costs very simple and just use plasterboard, painting (walls only) and tiling costs. Please keep in mind there are many other costs associated with doing something like this and we’re only using a few items to keep it simple and demonstrate how the dimensions of a space affects these 3 costs.

SPACE A: SQUARE SPACE

The first area is a 10 x 10 square with a 3 x 3 square bathroom with full wall tiles. Let’s say the rate for supply and install of plasterboard is $50/m2, the supply and install rate for tiles is $100/m2, the painting rate is $24/m2

Wall Schedule for House:

Total Plasterboard Cost = $5400
Total Painting Cost = $2592

Wall Schedule for Bathroom:

Total for full wall tiles = $3,240

Total Cost for Space A = $11,232 or $112.32/m2

SPACE B: RECTANGULAR SPACE

The second house is a 20m x 5m rectangle with a 4.5 x 2 rectangular bathroom with full wall tiles.  Again, the rate for supply and install of plasterboard in $50/m2 and the supply and install rate for tiles is $100/m2

Wall Schedule for House:

Total Plasterboard Cost = $6750
Total Painting Cost = $3240

Wall Schedule for Bathroom:

Total for full wall tiles = $3510

Total Coast = $13,500 or $135.00/m2

SUMMARY

So both houses are 100m2 with a 9m2 fully tiled bathroom. But there is a difference in cost of $2,268.00 or $22.68/m2 between the two.  This is a big difference for a relatively small space.  Now, add in all the different variables like VJ Board vs plasterboard or half tiled walls vs full tiled walls and you can see how difficult it is to come up with a square meterage rate.  And we haven’t even looked at kitchens (2 pack vs vinyl wrap, stone benchtop vs Laminex benchtop).  The variables are simply too great to simplify it down to one number.

Yes, each trade can give you a square meterage rate or a lineal meter rate (as we’ve done above with plastering, painting and tiling). But other factors, such as the shape of your space, means it’s more difficult to give a square meterage rate for the total cost of the build.