"Must be expensive, no way it is profitable"I agree. In the Icon...

"Must be expensive, no way it is profitable"

I agree. In the Icon video posted recently, the CEO said that they will eventually be able to build for a cost of $25 per sq ft.

I am not sure what that means - is it sq ft of wall area, or sq ft of floor area? Either way I did this back-of-the envelope calc.

For a typical 1 storey simple medium size (? these days?) 4 br house with attached double garage on flat land, total floor area 230 sq m, I computed this:

wall area: 440 sq m (I counted the external wall twice - for the double skin, and removed the spaces taken by doors and windows)
using typical blocks (390*190*90) for everything, we need 5940 blocks (would be less if using mortar because of the joints)
Midland Brick sells them for $3 each

I used FBR's build estimate here https://hotcopper.com.au/posts/74490920/single - the H109+ line to be conservative
the estimate is $25/sq m for blocks 390*230*90. So, for the smaller Midland Brick I will use $30 /sq m

So FBR cost to build is: 5940*3 + 440*30 = 17,820+13,200 = $31,020

Time to build: 5940/250 = 24 hours (obviously will be less with h110, and cheaper)

Icon calc:

conversion factors 1 sq ft = 10.76 sq ft
1 $US = 1.50 $AU

calc 1: assume $25/sq ft relates to wall area
wall area = 440 * 10.76 = 4734 sq ft
cost $US 25 / sq ft
wall cost = 4734 * 25 * 1.5 = $177,525 !!! this is crazy, so the $25/sq ft must apply to floor area

calc 2: assume $25/sq ft relates to house floor area

floor area: = 230 * 10.76 = 2474 sq ft
wall cost = 2474 * 25 * 1.5 = $92,775 !!! still crazy

OK - maybe there are other costs that should be added to FBR's costs to make the comparison fair, eg
- rio, wall ties, lintels
- cost of glue? (surely that is already included?)
- chasing for services
- render & paint or lining with gyprock and then paint? (ie is Icon's printed wall finished or does it need to be painted?)
- does Icon's cost include the fitting of windows and door frames?

The difference between FBR and Icon costs is huge - have I got it seriously wrong? Any ideas anyone?