When we started out trying to cost and plan for our extensions it felt a lot like we were trying to squeeze information out of the illuminati. Hunting down prices for materials really requires quotation after quotation, and labour pricing can be found on various guide sites but they are averages. In a place like Sydney, those averages can mean almost nothing. Sometimes before bothering to start the design process, or before bothering to submit a DA ..it’s normal to want “a rough idea”. Something you can stomach and understand. Home magazines sometimes give a breakdown. Tiles, joinery and such can sometimes like eye watering on those estimates. But nevertheless, this is reality.
My rule of thumb is not to overwhelm oneself with information. It’s impossible to know everything. You only really need to know about every risk. After that, pick your best sources and keep going back to them. For anything else, talk to people such as your suppliers – they are a wealth of knowledge.
The best places I found for getting “a rough idea” of prices before starting are below:
- Home Improvement Pages
- Whirlpool Forums (just make note of the dates of the blog posts)
- The Owner Builder Blog/Magazine (Several links from this site go to actual owner builder blogs where costs are discussed)
For information on energy efficiency you can’t got past:
Major Material & Service Costs (Labour separate)
Without boring you with the cost of every nail and screw (you’ll need lots of them is all you need to know), I’ve listed the “major” costs: things like roofing, framework and so on. I’ll add to this list as we go along.
Compliance Documentation & Insurance
Construction Certificate, Inspections, Occupation Certificate fee Essential Certifiers
Development Application fees – this is dependent on your project and council area
Owner Builder Construction Insurance also advisable.
Structural engineering $5000-$7000 budget including inspections SDA Structural Engineers
Stormwater/drainage (Hydrolic engineering) as requested by council Budget $3000 Liquid Hydraulics & Civil Engineers
TIP: Budget for $15,000-20,000 including tipping
Includes drainage pit dig, lay pipes and blue metal and fill
Foundation dig for living extension footings
Foundation dig for garage footings
Southern wall (garage) dig for Ag pipe
Tipping alone was $5940 (unbelievable I know but clay and soil has be tipped properly and when you see these guys moving soil, you would not want to even attempt to do this yourself. Ours took 2 days and several double-tippers several visits.
TIP: Budget for $40,000 just the pool, add $30,000 for landscaping, decking/tiling, compliant fencing.
(Not including digging, coping or water line tiles supplied by us). Iguana Pools
Pool coping Ivory tumbled travertine Stone Wholesalers
Best to contact by phone or go there
Pool tiles Spanish mosaic TFO
Best to go there and order over the counter
Pool fencing & stainless steel spigots
Everton via Bunnings, inquire about their owner-builder power pass/discount card
Structural Timber & Cladding
TIP: Budget for $50,000 – Eatons
Includes all structural timber, LVLs and Weathertex hardwood cladding to-date. Eatons are great to deal with, quick to deliver, well priced and tradespeople generally ring in their orders of a morning.
TIP: Budget for $3,000-5,000 but it depends on your design and amount of space needing brick.
Southern Highlands Building Supplies
Very helpful and a fast turnaround. We gave them the brick dimensions of the original house bricks, and they suggested Smooth Common since we are painting the bricks. At 0.65 cents/brick it’s hard to beat.
TIP: Budget for $10,000 not including carpentry – Barrenjoey Timber
It pays to shop where tradies shop. Our deck is approximately 100 sqm of Iron Bark. Including the labour of our 2 carpenters for 1.5 weeks, this brings a very large deck to approximately $22,000 when we know that it could have cost as much as $380/sqm installed by a separate contractor.
TIP: Budget for $15,000-20,000 not including installation – The Roofing Supermarket
Includes new Colorbond Lysaght Kliplok 700 roofing across the original house, and roofing for the two new extension volumes, roofing insulation and custom made Colourbond box guttering. Kliplok 700 is concealed fixed cladding with no exposed fasteners for weathertight roofs.
Included in the timber budget above, we were thrilled about Weathertex. This is a unique Australian hardwood product which is compressed and created by a machine that only exists here. It is 97% hardwood and 3% wax and is ideal for lightweight, sustainable building. It comes pre-primed in a number of textures and profiles. We sought advice from Weathertex and then place our order with the Bunnings Trade Desk.
All Windows & Doors
Moar Windows & Doors We budgeted $50,000 (also includes replacement doors/windows for existing house)
Highly dependent on the number of windows, doors and types of glass you need. We had around 26 pieces in total which is the whole house. Some were large windows and doors and were Low Emissions glass. Others were standard. The team at Moar Windows and Doors is outstanding.
Carpentry (Building not joinery) (i.e actual construction including labourers for all framework, cladding, roofing)
Budgeted $100,000 – $150,000
Our builder was Kitt Constructs (Kitt Nilsayam) Young, energetic, experienced in building standard homes but open to new things, lovely to deal with, easy to talk to. Additional decking & cladding MB Building Services (Matt Bate) Ditto for Matt – he is bright, quick to work, great precision and speed.
Plumbling Budgeted $10,000-$15,000 Woollys Waterworks
Includes running pipes to the drainage pit as per the engineering plans (approx 20 metres), a gully for the pool (approx 30 metres), replace repair and reconnect kitchen pipe. The next major plumbing task will be the water tanks, and finally the master bathroom. These guys are fast and energetic.
Turramurra Electrical (Jack) Budgeted $10,000 spent $7700.
Removing powerlines and putting them underground (not including digging, that’s part of our excavation activities). Suck up the cost, it’s worth it. Jack was reasonable compared to other ASP Level 2 certified electricians.
Procision Electrical Budgeted $10,000
We haven’t yet had to wire the extension but that’s coming up. So far, emergency re-wiring after the October rain damage was needed. Michael & Chris are great and on-site fast.
Cost of bricklayer, steel, welding or landscape costs not listed as it depends on your requirements.cBe v