WA - West Leederville 6007, 3 unit development

What info do you need to supply the builders when tendering for a job?

  • Full construction drawings (not DA drawings). Does this include all stuctural drawings? yes working drawings are a must. structural drawings too, if you want the price to be a quote with low margin for error vs an estimate
  • Feature and Contour Survey - yes but you would already have this if youve applied for DA
  • Certificate of Title - Proof of ownership you wont need this initially although some may ask for it. when you sign the contract it will be needed
  • Watercorp Flimsy (ASCON) drawings for showing the connection from the mains sewer into each property yes, its a $30 odd dollar item just give it to them.
    [*]Specification - eg What type, style and number of dwellings and the level of finish. style and number of dwellings etc will all be in your approved plans. more importantly you should try to specify PS/PC sums for certain items that will be allowed for differently by different builders. Eg if you specify say $15k for balcony screens, $40/m2 for tile supply, allow for large vitrified tiles if thats what youre going to put down, $3k per dwelling for aircon etc then what happens is that builders will be quoting like for like. It is a lot more upfront work this way but you will have a better chance of choosing between builders
  • Scope of Work - who creates this?
  • Schedule of Finishes - who creates this? you in conjunction with your building designer
  • Soil report - has a large bearing on costs and slab/footing or is this taken care of during the creation of the structural drawings?

Which items above are mandatory or will help the tendering process by taking alot of the guess (hard) work out for the builder?

Do you need to supply them with a bill of quantities or is this what they calculate? i believe BOQ is done by estimaters and quantity surveyors so it will be on their end and not yours. for a large development it may be something you do but not likely for a smaller one


ive answered above
 
Overall Tano, the more details you can give a builder up front in the tender, the more accurate their responses back will be and the more comparable they will be between builders.

In my case we are yet to have structural drawings done, so the builder has only allowed a costing on what they think is required. As Sanj suggests, this is a figure at risk of increasing (they never seem to go down do they!?) if the engineer decides to be overly cautious in what is structurally required.

Conversely, my spec list in parts is very specific, some of the items specify the brand and model numbers so theres zero ambiguity.

You can have a soil report done before securing the development site, just put it as a condition in your offer.

A risk of not engaging builders till after DA approval is that you may find you have an approved design that does not fit within your available budget/finance limits. Designers and Architects can certainly aim to meet an expected budget, but the builders will have the final say on what it will cost.

In my case, I am playing in the upper end of my limits in regards to financing this project, so I wanted some comfort as early as possible that I wasn?t over extending myself trying to incorporate all the items on my wishlist.

Of course a negative aspect is that I essentially only have an estimated cost at this stage, as I don?t have DA approved plans. Note that I havent signed full contracts with the builder yet, only committed to them through a PPA.
 
The other benefit Skuttles had with going in early with the builders was that he could sit down with them pre-DA and say 'what would you recommend changing' because there can be that gap between design worthy and build worthy. It's nice when the 2 meet but sometimes a designer will create an overly complicated roof line which costs $$$$ or in Skuttles case it was non standard window sizes which ups the price of window fittings etc.
 
If you're interested in energy efficiency, then my brother (who studied eco building) reckons that the way to go is brick construction, no cavity, and external insulation.

That's what the Germans do. :)

Basically the brick gives the building thermal mass, which means it heats up and cools down slowly, so the temperature is more constant. It's the weight of construction that gives it this property, whereas a lighter building, such as a timber frame, will have more rapid temperature fluctuations.

You want the thermal mass inside the insulated envelope, as otherwise it'll be ineffective. Hence the preference for external insulation.
 
If you're interested in energy efficiency, then my brother (who studied eco building) reckons that the way to go is brick construction, no cavity, and external insulation.

That's what the Germans do. :)

Basically the brick gives the building thermal mass, which means it heats up and cools down slowly, so the temperature is more constant. It's the weight of construction that gives it this property, whereas a lighter building, such as a timber frame, will have more rapid temperature fluctuations.

You want the thermal mass inside the insulated envelope, as otherwise it'll be ineffective. Hence the preference for external insulation.

This is called Reverse Brick Veneer where it is a single leaf of bricks then the outside clad in various forms (eg fibre cement, weatherboard, master wall, SIP etc) and insulation.

The construction we have in WA is brick, cavity, brick which has quite bad thermal efficiencies even though it has good thermal mass.

A fully timber framed building with insulation can outperform a double brick house quite easily.
 
The other benefit Skuttles had with going in early with the builders was that he could sit down with them pre-DA and say 'what would you recommend changing' because there can be that gap between design worthy and build worthy. It's nice when the 2 meet but sometimes a designer will create an overly complicated roof line which costs $$$$ or in Skuttles case it was non standard window sizes which ups the price of window fittings etc.

Good point Westminster, builder pointed out a few things. Saved about $1200 on changing 5-6 window sizes slightly. Best result was saving $1400 per apartment ($4200k total) by reducing the stone benchtops lengths 400mm, thereby only needing 2 instead of 3 slabs of stone per apartment (or ot may have been 3 instead of 4!?, cant remember off hand).
 
If you're interested in energy efficiency, then my brother (who studied eco building) reckons that the way to go is brick construction, no cavity, and external insulation.

That's what the Germans do. :)

Basically the brick gives the building thermal mass, which means it heats up and cools down slowly, so the temperature is more constant. It's the weight of construction that gives it this property, whereas a lighter building, such as a timber frame, will have more rapid temperature fluctuations.

You want the thermal mass inside the insulated envelope, as otherwise it'll be ineffective. Hence the preference for external insulation.

Thanks Garemsay, always happy to hear opinions on this subject, it seems such a black art to get information on the pros and cons of each type of construction.
 
Quick Update

Preliminary DA assessment has been done by Town of Cambridge in 26 days, hope the rest of the assesment period is just as prompt (famous last words)

14 points to address but nothing hugely concerning. 6 will be altered on the plans to comply, 6 we will try to justify and 2 my designer will be seeking clarification as to what drugs the planning officer was on at the time of his assessment (both his plot ratio and overshadowing calcs were WAY different to ours)

Council has also confirmed that the plans will require adjoining neighbours comments. We are currently proposing a long parapet wall on one boundary for the tandem car bays, so will be interesting to see if the neighbour responds.

In the background have been securing rental appraisals from local RE agents to 'assist' the loan officer with my upcoming construction finance application.

Random event - drove past a few weeks back and there was a beat up old Landcruiser parked on the block. Assuming it was a cheeky neighbour I left a note politely telling them to bugger off and park elsewhere. Was still there the next day so reported to police and council. Turns out the police had been looking for it as it was involved in a few nefarious activities, but by the time they visited the block/contacted me the car was gone and hasn't returned.
 
Last edited:
No cavity brick construction does nothing to stop damp wicking through the walls.

It might be energy efficient, but you're living with damp, rot and mould.
 
No cavity brick construction does nothing to stop damp wicking through the walls.

It might be energy efficient, but you're living with damp, rot and mould.

I think graemsy meant reverse brick, ie brick inside, insulation then a waterproof outside (be it what you want).

For double brick yes you have to have the cavity because brick is porous and allows water/damp in
 
Random event - drove past a few weeks back and there was a beat up old Landcruiser parked on the block. Assuming it was a cheeky neighbour I left a note politely telling them to bugger off and park elsewhere. Was still there the next day so reported to police and council. Turns out the police had been looking for it as it was involved in a few nefarious activities, but by the time they visited the block/contacted me the car was gone and hasn't returned.

I like the note thing:), I am a nazi when it comes to people parking on my verge, living in inner city, verge is sacred.... bugger off;)
 
For double brick yes you have to have the cavity because brick is porous and allows water/damp in

....which is no problem, if you have openings instead of windows and doors.

but we don't - and we paint our walls, sometimes plaster them too.

we fit carpet up to the edges of these walls, sometimes fix wooden cabinets to them as well.

i have no problem with the energy efficiency of solid mass walls - they just need to encourage draughts to reduce moisture build up - which kinda kills the efficiency of the home again.
 
There are weep holes at 1200mm centres on the external brickwork on the first course. Then the slab edge is parged with a waterproof membrane (and where the slab sits on the footing it has a membrane) so moisture cannot leech up the internal leaf of brickwork. The cavity breathes and expels moisture via the weep holes (also located on window frame sills from the manufacturer). Moisture also cannot bridge the cavity as the wall ties have drip grooves. Under and above windows is alcor flashing that runs down and away from the internal leaf, taking moisture to the outside leaf.

Cavity brickwork is far from perfect in regards to energy efficiency, but it is excellent in regards to keeping moisture out as all moisture is kept to the external leaf via all systems above (more so on first floor with the cavi-dry systems/tray flashings etc).
 
Back
Top