Knock down or renovate

I’m interested in some general advice.

We want to add a second story and pretty much redesign the first floor. Only the 4 outside walls would potentially stay. 5 bedroom house about 330sq mtrs if we do everything which includes 7x8 garage.

I’m getting conflicting price points and wanted to see whether to renovate or simply knock down and start over.

We are looking at medium finish and the volume builders for total rebuild are about $1350-1500/ sq mtr and custom builders to Renovate are $2100-2300/ sq mtr.

We are on a flat block. But the price difference is massive.

Are we better off just doing a demo and starting from scratch with a volume builder whose plan we like?

Am I missing something here? I know volume builders take 5-6 months longer, but it’s a difference of potential $150,000 to renovate vs start over.

Are there substantially more costs associated with a new build?

Thanks everyone!

[quote="rebe3719"]I’m interested in some general advice.

We want to add a second story and pretty much redesign the first floor. Only the 4 outside walls would potentially stay. 5 bedroom house about 330sq mtrs if we do everything which includes 7x8 garage.

I’m getting conflicting price points and wanted to see whether to renovate or simply knock down and start over.

We are looking at medium finish and the volume builders for total rebuild are about $1350-1500/ sq mtr and custom builders to Renovate are $2100-2300/ sq mtr.

We are on a flat block. But the price difference is massive.

Are we better off just doing a demo and starting from scratch with a volume builder whose plan we like?

Am I missing something here? I know volume builders take 5-6 months longer, but it’s a difference of potential $150,000 to renovate vs start over.

Are there substantially more costs associated with a new build?

Thanks everyone!

That's a big House and great size garage.. .. I would have built a larger garage

It's hard to tell without photos and further information
Points to consider
1. Is your current house worth renovating Vs the new house build?
2. Ideally you would need to Design/Model both options, view Pros and Cons, extract data, costs and compare
and most people don't
3.They go the easy option... new house get 3 quotes and compare the market
4.Rule of thumb, Renos cost 30-50% more than a new build,
As there's more work involved in repairs, compliance, and Overheads,etc,etc


There can be
1.if you don't compare & check costs
2.If you dont have the soil report eg Geotech
3.Engineering costs are firmed up after you have committed, by that time you are locked in
4.Work out the surprises before hand, own copyright of the plans and Data, get 3 quotes, Pick your preferred builder and negotiate a fair price

Well I guess that’s not comparing apples to apples. Custom builders cost similar whether it’s to renovate or total rebuild, and the quote you got seems about right. You’ll get a better quality build and one designed specifically for your site, your lifestyle and needs.

Volume builders don’t renovate of course, and are cheaper due to economies of scale. On the flip side, options are limited and site supervisors can be spread rather thinly over multiple builds, so quality can be affected.

Compare the buildings DNA-> Basic Building Material, Units & costs -> Concrete$ per m3, steel Tonnes, Brick$ per 1000 ,Timber$ per m, etc
Also, the Bim data and information also comes in handy during the build, when checking. hth