A guide for a trouble-free building : Tyrrells

A guide for a trouble-free building

October 18, 2019

Tens of thousands of building projects go wrong every year. Most of the trouble starts from a combination of errors and omissions in the plans, a bad relationship with the contractor, mistakes and mismanagement by the contractor and your failure to make sure the building quality is OK.

Building projects should go right. They can be creative, exciting and a financial windfall. The way to do this is to understand the responsibility of each participant. You are the main reason the job will go smoothly.

1. Plan Check

Consumers and builders often assume their drawings are complete and correct. This may not be the case even when dealing with architects and experienced designers. The drawings may look great, but are they right? Remember the builder will build what is on the plans.

Detecting problems on the plans before any work commences will save you money, time and the nightmare of a dispute with the builder.

A careful PlanCheck will help you:

identify mistakes and omissions before obtaining quotes
help minimise confusion and expensive variations.

For instance, the builder may use inferior paint unless the quality is specified in the documents.

You can do most of this yourself with the following checklist. With complex projects, it may be necessary to get a professional to do the PlanCheck for you.

1.1 Getting Started (before construction begins)

Issue	Assess/check	Recommendations/review
Condition of adjoining structures	adjacent structures especially on adjoining boundaries  fences, screens, walls retaining walls especially on or near boundaries  kerb, gutter, footpath, verge road surfaces service access, grates, cover	a photographic record may be required  dilapidation reports may be required  engineer’s opinions required  annex records/reports to contract copy record to affected parties e.g. neighbours, council, supply authority protection to be provided by the contractor highlight items to be protected
Damage to public utilities	sewer access, vent water gas  stormwater electrical poles, wires	contractor to locate all services  drainage diagram provided identification survey provided client indemnity against any damage  protection to be provided by the contractor?
Site considerations	aspect mainly; north/ south/east/west  orientation of building  views, outlook, privacy exposure slope and drainage overshadowing/privacy by adjacent property  by proposed structure surface run off from adjoining properties	access to sunlight – shading/protection  north-south breezes – also see amenity N/NE to N/NW aspect for living areas  best use of – affectation by others  durability/design to terrain category relocate shaded areas, openings  review building envelope  arrange pre-approval meeting with Council or certifying authority
Adverse influences	trees affecting structure/services soil stability, e.g. reactive soils erosion control  termite colonies/activity access  excavation in rock bad or filled ground  ground water/water table contamination – asbestos, lead, fuels, poisons, other pollutants	obtain an opinion of arborist/tree surgeon clarify council removal policy obtain an opinion of geotechnical engineer (see council soil maps) obtain indicative rates for retaining walls/drainage risk assessment trees/stumps/roots/debris PC to locate, destroy & monitor colony  contractor to include temporary access  safe manoeuvrability – ingress-egress  permanent access costs and site security obtain indicative rates for rock excavation, de-watering, pier & beam construction, back-filling, compaction obtain indicative rates for removal of contaminants – EPA approvals
Condition of any existing structures	Identify, seek further advice about: structure concealed damage – termite  re-use of materials – roof tiles, windows, gutter, etc. services – electrical, sewer, water, air handling, lift, fire services  trees and vegetation	Check or obtain: original drawings/specifications pre-purchase reports timber pest reports  pre-construction report engineering details/reports other specialist advice  clarify the protection of trees/vegetation
Consultants you need	Surveyor  Building designer/architect Structural engineer including: Geotechnical advice Hydraulic engineer  Electrical engineer Mechanical engineer  Approval	site and contour survey  drawings including shadow diagrams  specification Council D/A and construction certificate  heritage impact statement soil classification structural drawings  for complex drainage systems  for larger installations  for complicated air conditioning check conditions of consent
Fees and costs	Council D/A Construction certificate  Consultants costs Sydney Water  Fee rebates/refunds	Select either local Council or accredited private certifier If any doubt clarify onus for costs and fees Payable by who?

1.2 Approvals

When you want building work done you need to obtain Development Approval, Construction Certificate and Compliance Certificates from either your local council or an accredited certifying authority. Your local Council does not take responsibility for their approvals, whereas an accredited certifier may (under legislation) be liable for their work.

1.3 Dimensions that work

Why not check your room sizes and other important measurements

Item/area	Acceptable min .dimension			Comment/recommendation
Generally				Check circulation, flow, linkages between spaces BCA sets out the required ceiling heights
	width	length	height
Hall	1m		2.43m
Living areas	3.6m	4.2m	2.43m
Dining room	2.7m	3m	2.43m
Bedroom	2.7m	3m	2.43m	3.0m preferred minimum
Main bedroom	3.6m	3.3m	2.43m
WC	1.05m	1.6m	2.43m	2m with inward opening door
Bathroom	2.1m	2.4m	2.43m
Ensuite	1.2m	2.1m	2.43m
Kitchen	2.4m	2.4m	2.43m
Laundries	1.6m	1.35m	2.2	1.8m length preferred
Balconies	2.4m	3m
Stairs	0.9m 1m preferred		2m	Riser 165 -170mm preferred -190mm max. Tread width including nosing 275 – 290mm. Avoid winders, single or double steps. Non-slip surfaces/nosing.
Robes & cup’s		600mm		800mm in laundry
Shelves
linen			450mm apart
pantry			450mm apart
hanging rods			1.65m from floor
Kitchen
worktops	600mm	600mm deep	900mm 950mm	Oven/grill height to suit the appliance
eating	350mm	450mm	760mm
fridge	700mm	450mm	1.65m	Allow for ventilation
microwave	600mm	450mm	400mm	Check exact appliance size
Laundry fixtures
wash machine(WM)	700mm	700mm deep		Can WM be installed without removing tub?
dryer	600mm		600mm	Can WM lid open under the dryer? Ceiling height to suit top of the dryer – minimum 2.2m
Laundry
bath	750mm	1500mm	450mm	to suit wall tile courses.
vanity top	600mm		810mm	WCs minimum 400mm from sidewall
shower	900mm	900mm
Windows				Centre of rooms, best use of view, margin over for curtains/blinds. Glass specified – safety, obscure, double
Sills over
WC/tub			1.2m	To suit bed, desk, etc. Water bars to door thresholds – outward opening external doors.
bedroom			0.9m
kitchen			1m
Doors				Check openings do not unduly affect room use. Locate to allow robe/cupboard. Clearance under to suit floor covering. Safety glass allowed.
generally	800mm
bathroom	700mm
entry	900mm
Hardware, switch heights GPOs (power points)	1050mm above floor			Switches and door furniture at the same height, deadlock security to windows and doors. Locate GPO’s above the skirting and to suit equipment.
Lights				Centre of rooms (allow for built-ins)
Tap-ware				75mm clear space all round tap head. Shower and bath taps easily accessible.
Balustrades			1m	Childproof, max 125mm opening, over drops > 600mm. Check material durability
Single garage	3m	5.5m	2.1m	6m preferred, 6.6m if workbench required.
Double garage	6m	5.5m	2.1m	Check height doesn’t limit the choice of a garage door. Windows may limit wall storage – skylights preferred
Eaves overhangs	450mm			600mm on the north side – 900mm preferred if glazing to floor

1.4 Amenity and services

Issue	Item/location/type	Recommendation/check	Notes
Natural light	dressing room ensuite WC bathroom hallway  stairwell  garage	10% of the floor area skylights/sky-tubes advised  glass blocks
Ventilation	internal rooms  laundry kitchen  rooms with showers windows as shown	5% of the floor area  north-south flow  mechanical recirculating delayed switch off connected to light check size, opening hand, type
Security	external doors  windows  garage	deadlocks alarm system  privacy latches	Check the type of overhead door automatic equipment.
Services	rangehood  dishwasher security  garage door TV antenna  exterior lights GPOs switch lights date cable smart wiring  hose cocks roof and site drainage system  gas reticulation hot water	interior & exterior  number & location – two-way for halls front – rear – balcony  DPs, sumps, drains shown Consider rainwater tank storage Retention pit required  number gas bayonets  type, size gas – solar – electrical	Check type, capacity and warranties of any mechanical equipment; e.g. who has arrived at AC capacity. Location close to fixtures Tray and drain (if interior) Pipework insulated
Thermal performance	sarking to roof ceiling insulation sarking/insulation to walls roof void ventilation air conditioning, room heating  underfloor heating	heavy duty – hail proof R3 roof R2 walls and ceilings wall insulation to be breathable  affect of roof glazing affect of large glass areas/aspect  thicker or double glazing to windows turbo/gable  compliance with codes  running costs of heating	Confirm NATHURS rating required by council
Soundproofing	noise between occupancies  noise between sleeping-living noise from external sources noise from services	insulate interior walls between  thicker or double glazing to windows  relocate or isolate service equipment

1.5 External materials and finishes

You will eventually need to chose what you want so why not do it now. We have found that is important to choose durable weather-exposed, materials and finishes.

Issue	Assess/check	Recommendation/review	Notes
Demolition	ownership of salvaged materials disposal costs including tip fees weather protection security of uncovered structures  approvals	clarify any possible misunderstandings  have you considered selling the existing building for relocation to another site?
Brickwork	bond and joint finish surface finish  joint colour  sill type – a minimum of 15 degree slope  control joints – 9m max moist masonry to garage, retaining walls, below DPC – salt wall/frame ties weep holes	check exposure class of bricks  raked – flush – struck – ironed face – bagged – render  is colour contamination likely; e.g. dark mortar on light brick identify the location of control joints conceal if possible behind downpipes will the area be used for storage? avoid coatings to damp brickwork  is cavity brick a good option? stainless steel – plastic	Especially for below damp-course, in-ground contact, coastal location, around the swimming pool
Roofing	any low pitched areas type of flashing specified sarking/insulation	check profile suitable for pitch warn of increased risk  check for dissimilar metals  paint coatings should not replace flashing  check thermal performance of roof
Walls	weatherboard  insulated	type/manufacturer specified pre-finish or paint finish colour specified  check thermal/acoustic performance  durability
Windows	sash type and hand  material/finish specified  distance from coastline	weather protection  check the direction of sash movement fly screens included? deadlocks included? obscure glass to bathroom/ensuite/laundry
Doors	timber – exterior thresholds	solid core preferred/minimum hinges  Did frame rebate from solid piece?  water bar to thresholds check durability of finish s top & bottom of the door painted  high rise where weather-exposed sub-sill
Steel elements	durability of lintels, brackets, ties, handrails, post bases  surface finishes to exposed structural steel	hot dipped galvanised at minimum stainless steel in marine locations and all fixings  specify paint system if not galvanised
Landscape	fencing  gates pergolas, awnings‚  retaining wall type/height  plantings and vegetation	material durability  treated timbers preferred fully galvanised fittings – stainless steel preferred engineer required/durability  check size, shading, root type avoid planting trees close to buildings, paving, fencing

1.6 Internal materials and finishes

You will eventually need to choose what you want – so why not do it now.

Issue	Assess/check	Recommendation/review	Notes
Floors	particleboard floor  timber floors  ventilation under	rough sand of joints included consider any requirement for future polished floors species and grade identified expansion joints  clear of walls  type of finish specified wall vents @ 1 metre
Floor and wall tiles	walls – floors – fittings  expansion/control joints floor wastes & falls in floors hob – waterproofing advantage versus access obstruction	check wall heights detail any pattern work  detail location of all fittings  specify grout colours anti-fungal grouts show floor drainage on plan	Also, see PCs
Bathrooms and ensuites	vanity cabinet  bath shower screen	width – water resistant acrylic enamel sliding swinging frame less	Also, see PCs
WC	basin included  mechanical ventilation	widen WC to 1050mm  door opening outwards
Laundry	chute provided from 1st floor storage cupboard	broom storage ironing station exhaust for clothes dryer
Kitchen	wall mounted cupboards  pantry storage  under bench storage location of the fridge, oven  exhaust fan  benchtops  door swings of DW, oven, fridge to adjacent cupboards	fully lined corner use  microwave shelf pull out drawers vented to exterior 180-degree bull-nose edge integral splashback 100mm high	Also, see PCs
Bedrooms	wardrobe size satisfactory wall space	check GPO location
Entry	cloak cupboard	hanging space in cupboard protect door from weather
Wardrobes	swinging or sliding doors height of shelving/rails	robe details in documents  hanging rails included mirror doors identified
Fixings	skirting mould/size specified  architrave mould/size specified timber species specified	reject MDF in wet areas
Stairwell	useful cupboard under lighting  balustrading	lining?

1.7 Trouble spots

These are the areas that commonly cause problems that can be very expensive to fix later.

Issue	Assess/check	Recommendation/review	Notes
Basements	adequacy of ventilation and light detail & location of drainage  type of waterproofing  termite protection measures  retention of soil embankments	access to or cleaning of drainage check waterproofing warranties  check termite warranties (3660.1) soil level below floor level use moisture/termite/rot-resistant materials	Provide detail drawing
Roofing	any low pitched areas complex details  geometry e.g. octagons, curve. splays concealed gutters e.g. box  changes in pitch (flashing)  penetrations e.g. skylights, dormer windows  weather exposure	check profile suitable for pitch identify areas needing special care  manufacturer warranty no reliance on sealants durable, adequate size, overflows, access for cleaning adequate downpipes  anti-ponding board under sarking	Warn of increased risk of water penetration
Roof glazing	pre-made units  proprietary systems	use systems that are purpose made for roof installation avoid timber-framed on site
Slab on ground	engineer	engineer to inspect and certify design, placement (vibration) and curing including piers drop beams  all slab
Termites	termite protection split levels  basements  building on boundaries  slabs on ground  construction joints clearance / access	clarify method and ongoing maintenance costs, warranties and compliance with 3660.1  low risk methods – slab edge exposure, steel or treated timber frame minimum 400mm below floor frame detail the inaccessible entry points
Waterproofing	balconies above habitable rooms  basements including ground levels above internal floor levels wall cavity drainage above habitable rooms  membrane roofs rooftop terraces planters bathrooms, ensuites, laundries	step down from the interior membrane specified – 2 layer sheet membrane preferred  expansion joints detailed in large areas of tiles including perimeters  drainage outlets specified emergency overflows specified minimum 38mm upturn for hob-less shower provide detailed drawing
Contract	DFT preferred  Include a list of all documents including engineering drawings, schedule of finishes Agree completion date Request retention  Agree liquidated damages (weekly payment for any time overrun) Agree schedule of progress payments	Review all insurance – obtain certificates of currency for: home building warranty worker’s compensation  public liability.  Understand the process required to vary costs, materials, design or time for completion. Describe the stage that must be reached for each progress payment

1.8 Price check

It is your responsibility if you knowingly accept a price for that work that is too low for the quality and complexity set out in the documents.

It is always best to reality test the price by asking:

is the price significantly lower than the other price or prices?
is the price per m2 close to the usual cost for this standard of work?
does the price include expensive items such as complex shapes or roofs?
are there likely additional extra costs such as limited access, extensive excavation?

Likely cost per square metre

	Architect designed	One off buildings	Project and package
Basic quality	$1,500	$1,100	$700
Above average	$2,000	$1,400	$900
Premium quality	$2,500+	$1,800	$1,400

The contractor‘s quotation will include estimates of the costs of items that require your personal selection. Once you have selected your fixtures, appliances and accessories, you can either supply these yourself or the contractor can purchase them and reconcile any cost differences. If you know what you want, you will know exactly what the cost will be for each item. Preferably, request the contractor to supply and fix all items or clarify who will otherwise be responsible for delivery, insurance and faults in any item you provide.

Item	$ advised	Item	$ advised
kitchen cupboards	$	built-in robes – B1/B2/B3	$
sink	$	linen	$
dishwasher	$	cloak	$
hotplates	$	doors	$
oven/wall oven	$	door hardware	$
range hood	$	light fittings	$
microwave	$	carpet floor covering	$
exhaust fans WC/kit/bath/ensuite	$	vinyl floor covering	$
wall tiles laundry kitchen bath ensuite WC	$	laundry tub & cabinet	$
floor tiles laundry kitchen	$	dryer	$
bath ensuite/WC	$	washing machine	$
thresholds & sills	$	hot water service	$
vanity basin bathroom/ensuite/WC	$	air conditioning	$
vanity cabinet bathroom/ensuite/WC	$	heating & cooling	$
basin WC	$	underfloor heating	$
bath ensuite	$	security/intercom	$
spa including motor bathroom/ensuite	$	garage door equipment	$
toilet suite bathroom/ensuite/WC	$	auto entry gates	$
shower screen (S&F) bath ensuite/WC	$	entry door	$
wall cabinet bath ensuite/WC	$	entry door hardware	$
towel rails heated towel rails	$	security doors – front/ back	$
bath ensuite/WC	$	skylights	$
soap holder	$	TV aerial & circuitry	$
bath ensuite/WC	$	fencing and gates	$
mirror bathroom/ensuite/WC	$	clothes line	$
tap-ware laundry kitchen bathroom ensuite/WC	$	paving	$

1.9 Provisional allowances

The contractor usually includes estimates for parts of the work that can’t be costed because of incomplete information or unknown factors. Common provisional allowances include service connections, excavation, foundations, removing or importing fill.

Item	Allowance	Notes
Sewer drainage and connection
Water service
Gas
Electrical connection
Excavation
Piering
Importing fill
Exporting fill including tip fees
Access
Rock excavation
Retaining walls
Other

2. Selection of Contractor

Like any good relationship, a successful building partnership starts with a careful choice of partner. There are many ways to find the right builder:

word of mouth
- friends and relatives whose judgement you trust
- professionals, such as architects, engineers, tradesman and suppliers
previous contractors you have liked working with
building associations
names from local jobs that you like the look of.

Once you’ve got some contractor names, why not check them out carefully:
ring their last 3 clients and ask:

was the contractor good to deal with
- did the project finish on time and budget
- were you satisfied with the quality
- how did the contractor handle the inevitable problems
- was the contractor a good communicator
talk to the contractor about your job:
- Is the contractor interested?
- Does the contractor ask lots of questions?
- Do you like the contractor?
- Has the contractor done lots of similar jobs?
- How can the contractor demonstrate to you they are right for your job?
get down to detail:
- is the contractor licenced?
- can the contractor provide insurance?
  - home building warranty insurance
  - public liability
  - worker’s compensation
  - all risk

3. Progress Inspections

You need to know the builder is complying with all the regulations and that the quality of his work is acceptable.

Even the best builders make mistakes. Their subcontractors may take short cuts. Supervision on most jobs is minimal and rarely looks in all the
hard to get to places such as the roof interior, under the floors and those flashing up on the roof.

Councils DO NOT take responsibility for the quality of the work and are often not called at the important times.

You need reliable independent advice at the key stages:

Inspection	Who should inspect
Footings	The engineer who designed the footings or slab
Frame (just before plasterboard linings are fixed, after all services and waterproofing is complete)	Building consultant
Final (when everything is finished)	Building consultant

4. Certification

You can ask the contractor to give you certain certificates when the job is finished. The contractor will get these from his subcontractors, suppliers or the engineer.

The certificates help verify the quality of the work to you and future buyers. If anything goes wrong with the work that was certified you will know who is responsible. This certification is like a pedigree or bona fide that everything is OK.

The typical certificates you might get on a residential building are:

Termite protection including a plan of the areas protected
Plumbing final certificate
Certificate of compliance for gas installation
Waterproofing certificates for the showers, bathrooms, laundry and balconies/planters above habitable rooms
Glazing certificate
Engineering certification of:
- piers, footings, concrete slabs, any non-standard beams, retaining walls and pools
- complex drainage systems
- roof trusses and frames from the truss manufacturer
Surveyor’s certificate proving the location of building in accordance with approved plans and a maximum height of the building (if required by Council)
Proof of final inspection*
Certificate of occupancy*.