Hidden Costs in Home Building: Avoid Budget Blowouts in New Builds & Knockdown Rebuilds

Building a home is an exciting journey — whether you’re starting from scratch on a new block or
replacing an old house with a knockdown rebuild. But many homeowners are caught off guard by hidden
costs that aren’t always included in a standard builder quote.

At Casaview Homes, we’re committed to upfront, transparent pricing. That means helping you
understand the potential provisional allowances that could affect your budget — so there are no surprises
later on.

What Are Provisional Allowances?

Provisional allowances (or PAs) are estimated costs for work that can’t be precisely calculated until after
your site is inspected or certain reports are completed. These are typically not part of base pricing and
can include things like:

• Site excavation
• Stormwater management
• Drop edge beams
• Electrical upgrades or access
• Kerb and gutter works
  These apply to both new builds and knockdown rebuilds ( link to knockdown rebuilds), though they may
  be more common or more complex in rebuilds.

Common Hidden Costs in Home Building

1. Drop Edge Beams

Relevant for: Sloping blocks, new estates, and rebuilds on uneven land
Drop edge beams are concrete reinforcements used on sloped sites to support your home’s slab and
ensure stability.
Why it adds cost: Required when the site has a fall or needs leveling. Not all sites need them, but when
they do, they’re a structural must-have.

2. Private Power Pole & Overhead Power Protection (Tiger Tails)

Relevant for: Older suburbs, knockdown sites, and new lots without infrastructure
If your property doesn’t have a compliant electrical connection or needs temporary overhead safety
covers, additional work is needed.
Why it adds cost: Tiger Tails (protective sleeves for overhead lines) and private power poles must meet
local energy authority regulations.

3. Kerb & Gutter Works

Relevant for: Knockdown rebuilds and corner blocks
Local councils may require upgrades to your frontage, kerb, or driveway access — especially during a
rebuild.
Why it adds cost: These are council-enforced works that may include new kerb and guttering, footpath
adjustment, or vehicle crossover changes.

4. Stormwater & Hydraulic Requirements

Relevant for: All homes — especially those on flood-prone or complex sites
Proper drainage design is essential to prevent flooding and meet council regulations. This can include
pipes, pits, detention tanks or custom engineering.
Why it adds cost: Stormwater plans may require civil engineering and specialised installation, especially
for rebuilds that change the natural flow of water.

5. BASIX & NatHERS Compliance

Relevant for: All homes built in NSW
These government regulations ensure your home is energy and water efficient. Every new build in NSW
must meet BASIX (link to basix article) and NatHERS standards.
Why it adds cost: Design elements like window glazing, roof insulation, and shading may need to be
upgraded to meet your site’s compliance score.

6. Easements, Tree Removal & Unexpected Site Conditions

Relevant for: All projects — especially knockdown rebuilds
Existing homes may be hiding costly surprises. Easements, sewer connections, rock removal, and
vegetation can increase costs post-demolition.
Why it adds cost: These site-specific factors can only be confirmed after detailed reports or demolition,
leading to changes in scope.

How Casaview Homes Helps Minimise Surprises

We’re not just a builder — we’re your project partner from day one. Here’s how we help you plan with
confidence:

• Fixed-price quotations with detailed breakdowns
• Site-specific inspections before you commit
• Transparent communication about provisional costs
• Over 30 years of experience building across Sydney