Owner-Builder's Guide: Hot Water Systems for Steel Kit Homes

Owner-Builder's Guide: Hot Water Systems for Steel Kit Homes

1. Introduction

Welcome, aspiring owner-builder! Embarking on the journey of constructing your own home, especially a modern steel frame kit home, is a monumental undertaking. It’s filled with challenges, learning curves, and immense satisfaction. One of the most fundamental comforts of any home is a reliable and efficient hot water supply. This guide is specifically designed to demystify the hot water system (HWS) selection and installation process for your steel frame kit home in Australia. As an owner-builder, you're not just constructing walls and a roof; you're creating a functional, comfortable living space, and hot water is a non-negotiable component of that comfort. This guide will walk you through the essential considerations, regulatory requirements, practical steps, and cost implications, ensuring you make informed decisions for your build.

Building a steel frame kit home offers unique advantages, such as excellent structural integrity, termite resistance, and often quicker construction times. However, these modern construction methods also require specific considerations when integrating systems like hot water. We’ll specifically address how steel framing, often made from high-quality materials like TRUECORE® steel from BlueScope, might influence your HWS choices and installation. This guide is tailored for you, the beginner owner-builder, meaning we will explain complex terms, highlight potential pitfalls, and provide actionable advice to empower you throughout this critical phase of your project. Our goal is to equip you with the knowledge to select, safely install, and maintain a hot water system that meets the specific needs of your family, your budget, and crucial Australian standards and regulations. By the end of this comprehensive guide, you’ll have a clear roadmap to ensure a consistent, efficient, and compliant hot water supply in your new home.

2. Understanding the Basics: Hot Water System Overview

Before diving into specifics, let's understand the fundamental types of hot water systems available in Australia. Each has its own operational principles, energy sources, costs, advantages, and disadvantages. Your choice will depend on factors like climate, energy tariffs, family size, water usage habits, and your commitment to environmental sustainability.

2.1. Energy Sources

Hot water systems primarily use one or a combination of the following energy sources:

• Electricity: The most common and often cheapest to install upfront. Can be storage-based (tank) or instantaneous.
• Gas (Natural Gas or LPG): Generally more energy-efficient than electric storage. Can be storage or instantaneous. Natural gas is piped, while LPG (bottled gas) is delivered.
• Solar: Utilises solar collectors to heat water, often with an electric or gas booster for cloudy days. Highly energy-efficient and environmentally friendly. Can be flat plate or evacuated tube collectors.
• Heat Pump: Electrically powered, but works by extracting heat from the air to heat water, similar to a reverse-cycle air conditioner. Highly energy-efficient.

2.2. System Types

a) Storage Tank Systems (Electric or Gas):

These systems heat and store a large volume of water in an insulated tank, ready for use. When hot water is drawn, cold water enters the tank and is heated. Available in various sizes (e.g., 25L to 400L+).

• Pros: Relatively low upfront cost (electric), reliable supply, simple technology. Gas storage can be more efficient than electric storage.
• Cons: Heat loss from the tank (standby losses), takes up space, can run out of hot water if demand exceeds capacity, electric storage can be expensive to run if not on off-peak tariffs.

b) Instantaneous (Continuous Flow) Systems (Electric or Gas):

These systems heat water on demand as it flows through a heating unit, meaning no storage tank is required. You get an endless supply of hot water, as long as the flow rate demand doesn't exceed the unit's capacity.

• Pros: Never runs out of hot water, highly energy-efficient (no standby losses), compact size, often eligible for rebates (gas).
• Cons: Higher upfront cost, can have a slight delay in hot water arrival, gas units require adequate ventilation and gas supply, electric instantaneous units can draw significant power and may require substantial electrical upgrades.

c) Solar Hot Water Systems (Solar Thermal):

These systems use solar collectors (panels) on the roof to absorb sunlight and heat water, which is then stored in an insulated tank, often boosted by electricity or gas during insufficient solar gain.

• Pros: Significantly reduced running costs, lower carbon footprint, government rebates often available.
• Cons: High upfront cost, reliant on sunlight, requires roof space for collectors and ground space for the tank, booster required for continuous supply (adds running cost).

d) Heat Pump Hot Water Systems:

These systems use refrigeration technology to extract heat from the ambient air and transfer it to water in a storage tank. They are essentially a reverse-cycle air conditioner for your hot water.

• Pros: Highly energy-efficient (can be 3-4 times more efficient than conventional electric storage), lower running costs, eligible for government rebates.
• Cons: Higher upfront cost than standard electric, can be slower to heat water in very cold climates, requires outdoor installation with good airflow, may have some operational noise.

Owner-Builder Insight: When selecting your HWS, consider your family's daily hot water needs. A common rule of thumb is 50 litres per person per day for storage systems. For instantaneous, ensure the flow rate (litres per minute, L/min) is sufficient for simultaneously running multiple taps. For example, a shower might use 9-12 L/min, and a kitchen tap 6-8 L/min. So, if two showers are running simultaneously, you'd need a unit capable of at least 18-24 L/min.

2.3. Key Terminology

• TPR Valve (Temperature and Pressure Relief Valve): A safety device that opens to release excess pressure or temperature from a storage tank, preventing rupture. Absolutely mandatory for all storage HWS.
• Expansion Valve/Tank: Accommodates the expansion of water as it heats, preventing excessive pressure build-up. Required for some closed-system HWS.
• Tempering Valve: A device that mixes hot water from the HWS with cold water to deliver tempered water (typically 50°C) to sanitary fixtures like showers, baths, and basins to prevent scalding. This is a critical safety device and an NCC requirement.
• Energy Star Rating/MEPS (Minimum Energy Performance Standards): Ratings indicating the energy efficiency of appliances. Higher stars mean greater efficiency.
• Small-scale Technology Certificates (STCs): Australian government incentives (rebates) for installing renewable energy systems, including solar hot water and heat pumps.

3. Australian Regulatory Framework

As an owner-builder, compliance is paramount. Australia has a stringent regulatory framework for building and plumbing, ensuring safety, health, and amenity. Hot water systems are heavily regulated under the National Construction Code (NCC) and various Australian Standards.

3.1. National Construction Code (NCC)

The NCC, Volume Three (Plumbing Code of Australia - PCA), sets out the technical provisions for plumbing and drainage installations in Australia. It's crucial for your HWS installation.

NCC 2022 Volume Three (PCA) References:

• H2.2 Provision for Hot Water: Requires the provision of hot water to sanitary fixtures, kitchen sinks, and laundry tubs. Defines acceptable methods of heating.
• H2.3 Temperature Control Devices: Mandates the installation of tempering valves or other approved temperature control devices to limit the temperature of hot water delivered to shower, bath, and basin outlets to a maximum of 50°C (45°C for early childhood centres, primary schools, and aged care facilities). This is a critical safety measure to prevent scalding.
• H2.4 Discharge of Heated Water: Specifies requirements for safe discharge from pressure and temperature relief devices, ensuring it's not discharged in a way that causes a hazard.
• Part H5 – Water Heating Appliances: Contains specific requirements for the installation, commissioning, and maintenance of water heating appliances, including clearances, ventilation, flueing, and protection from damage.
• AS/NZS 3500.4: Plumbing and Drainage – Heated Water Services: The primary referenced standard for HWS installation, detailing design, installation, and commissioning requirements. The NCC mandates compliance with this standard.

3.2. Relevant Australian Standards (AS/NZS)

Compliance with the NCC largely means compliance with the referenced Australian Standards. For hot water systems, the key standard is:

• AS/NZS 3500.4:2021 Plumbing and Drainage – Part 4: Heated water services. This standard covers everything from materials, pipe sizing, and installation methods to safety measures like tempering and relief valves. It’s absolutely essential for your plumber to adhere to this, and for you to understand its implications.
• AS/NZS 3500.1:2021 Plumbing and Drainage – Part 1: Water services. This covers general requirements for water supply, including connections for HWS.
• AS/NZS 5601.1:2022 Gas Installations – General installations. If you are installing a gas HWS, your gas fitter must comply with this standard. It specifies requirements for gas pipe sizing, appliance connection, flueing, and ventilation.
• AS/NZS 3000:2018 Electrical Installations (known as the 'Wiring Rules'). For electric or heat pump HWS, your electrician must comply with this standard, covering all electrical connections, circuit protection, and earthing.

3.3. State-Specific Variations and Regulatory Bodies

While the NCC provides the overarching framework, each Australian state and territory has its own plumbing and building regulations, often with minor variations or additional requirements. You must check your specific state's regulations.

Owner-Builder Action: Before you begin, contact your local council’s building department AND your state’s plumbing regulatory body (e.g., NSW Fair Trading, VBA) to confirm precise requirements, permits, and inspection schedules. Do not assume; verify. Even if your steel kit home supplier provides generic plans, modifications for HWS might require specific approvals.

4. Step-by-Step Process: HWS Selection and Installation for Your Kit Home

This section outlines a practical process for integrating your HWS into your steel frame kit home build.

Step 1: Assess Your Hot Water Needs and Site Conditions (Pre-Construction)

a) Determine Hot Water Demand:

• Number of Occupants: How many people will live in the home now and in the future?
• Usage Habits: Do people shower at the same time? How often do you run hot water appliances (dishwasher, washing machine)?
• Number of Hot Water Outlets: Count showers, baths, basins, kitchen sinks, laundry tubs.

b) Evaluate Energy Sources Available:

• Electricity: Always available, but running costs vary significantly with peak/off-peak tariffs.
• Natural Gas: Is natural gas connected to your property? If not, what's the cost of connection? (Can be several thousand dollars).
• LPG (Bottled Gas): Requires space for cylinders, regular deliveries/refills. Suitable for rural areas without natural gas mains.
• Solar Access: For solar HWS, evaluate your roof orientation (north-facing is ideal for collectors) and potential shading from trees or other structures. Ensure sufficient roof space and structural integrity (steel frames are excellent for this!).

c) Consider Climate:

• Cold Climates: May require larger storage tanks, better insulation, or more robust boosting for solar/heat pump systems. External plumbing in cold regions needs frost protection.
• Hot Climates: Solar HWS performs optimally.

d) Local Council & Utility Requirements:

• Check for any local council bylaws regarding HWS types (e.g., some councils encourage solar or heat pumps).
• Understand your electricity retailer's off-peak tariffs. Some solar/heat pump rebates are contingent on specific electricity plans.

Step 2: Select the Right Hot Water System

Based on Step 1, narrow down your options.

1. For Budget-Conscious (Low Upfront, Higher Running): Conventional Electric Storage (consider off-peak). Not ideal for steel kit homes trying to achieve highly energy-efficient ratings.
2. For Mid-Range Efficiency/Cost: Gas Continuous Flow (Natural or LPG) or a standard Electric Heat Pump.
3. For High Efficiency/Lower Running Costs (Higher Upfront): Solar Hot Water with gas/electric boost, or a high-efficiency Electric Heat Pump.

Kit Home Specific Consideration (Steel Framing):

• Mounting: Steel frames, particularly those using TRUECORE® or similar light-gauge steel, provide strong and even surfaces for mounting. Ensure your kit home manufacturer’s structural engineering verifies point loads for wall-mounted instantaneous units or roof-mounted solar collectors. Heavy storage tanks usually sit on a concrete slab or reinforced stand, not typically wall-mounted in timber or steel frame houses due to weight.
• Piping & Penetrations: Steel frames allow for clean and precise routing of plumbing within wall cavities. Ensure that penetrations through steel studs for pipes are done according to the kit home manufacturer's guidelines and structural engineer's specifications to avoid compromising structural integrity. Use grommets to protect pipes from rubbing against steel edges.
• Corrosion: While TRUECORE® steel is coated for corrosion resistance, ensure all plumbing connections, particularly outdoors or in damp areas, are correctly installed to prevent leaks that could lead to even superficial corrosion over time. Use appropriate pipe materials (copper, PEX) and fittings that are compatible with the local water quality and won't induce corrosion on adjacent steel if there's contact – although modern plumbing practices typically prevent direct metal-to-metal contact where corrosion might occur.

Step 3: Design, Placement, and Planning

a) Location, Location, Location:

• Proximity to Outlets: Place the HWS as close as possible to the most frequently used hot water outlets (e.g., kitchen, main bathroom) to minimise pipe runs, reduce heat loss, and speed up hot water delivery. This can significantly reduce energy waste.
• Outdoor vs. Indoor: Instantaneous gas units and heat pumps are often best placed outdoors for ventilation and noise. Electric storage can be indoors (garage, laundry, cupboard) or outdoors (requires weather protection).
• Clearances: Ensure manufacturer-specified clearances for servicing, ventilation (gas units), and flueing (gas units) are met. These are regulated by AS/NZS 3500.4 and AS/NZS 5601.1.
• Drainage: All HWS, especially storage tanks, require a safe drainage point for relief valve discharge. This must be connected to a dedicated tundish visible to the occupants, running to a drain or outside area where it won't cause damage or a slip hazard, as per NCC H2.4 and AS/NZS 3500.4.

b) Pipe Sizing and Materials:

• Your plumber will design the pipework according to AS/NZS 3500.1 and AS/NZS 3500.4. Proper pipe sizing ensures adequate flow rates and pressure. Common materials include copper and PEX (cross-linked polyethylene).
• Insulate hot water pipes, especially long runs or those in unheated spaces/outdoors, to reduce heat loss. This is an NCC energy efficiency requirement (NCC 2022 Volume 2, J5D4 for pipe insulation requirements).

c) Structural Support:

• Heavy storage tanks (e.g., 250L of water weighs 250kg) need a reinforced concrete slab or a purpose-built, structurally engineered support stand. This is particularly important for your kit home if the original slab wasn't designed for a heavy HWS in that specific location. Consult your kit home engineer.
• Roof-mounted solar collectors also impose significant loads. Ensure your roof structure, being steel frame, is designed to safely bear this weight, especially when filled with water and subject to wind loads. Your kit home supplier's structural engineer must approve this.

Step 4: Engage Licensed Professionals

As an owner-builder, you are not permitted to undertake regulated plumbing or electrical work yourself unless you hold the appropriate licences. For HWS installation, you MUST engage:

• Licensed Plumber: For all water connections, tempering valve installation, relief valve drainage, and gas connections (if gas fitter licensed). They will issue a Certificate of Compliance.
• Licensed Electrician: For all electrical connections to the HWS, including power supply, circuit breakers, and RCDs. They will issue an Electrical Safety Certificate.
• Licensed Gas Fitter: If the plumber isn't also a licensed gas fitter, you'll need one for gas HWS connections, flueing, and commissioning.

Owner-Builder Responsibility: While you are managing the project, the legal and safety responsibility for the quality of plumbing and electrical work lies with the licensed tradespeople. Always request and keep copies of their licences and compliance certificates. Obtain multiple quotes and check references.

Step 5: Installation and Commissioning

Supervise the installation closely.

1. Foundation/Mounting: Ensure the HWS is securely mounted or placed on its designated foundation.
2. Plumbing Connections: Verify all pipes are correctly connected, insulated, and free from leaks. Check that AS/NZS 3500.4 requirements for TPR valves, expansion control, and tempering valves are met.
3. Electrical Connections: Ensure the electrician has wired the unit correctly, with appropriate circuit protection (AS/NZS 3000).
4. Gas Connections (If applicable): The gas fitter will connect the gas line, check for leaks, ensure proper ventilation, and confirm flueing meets AS/NZS 5601.1.
5. Tempering Valve Check: After installation, the tempering valve needs to be set and verified to ensure hot water at the tap does not exceed 50°C. This is a crucial safety step and part of the commissioning.
6. Commissioning: The licensed trades will perform commissioning tests to ensure the system operates correctly and safely. Document these tests.
7. Inspections: Arrange for council or regulatory body inspections as required by your state. This is often a critical hold point in your building process.

Safety Warning (WHS Act 2011): As an owner-builder, you are considered the PCBU (Person Conducting a Business or Undertaking) on your site. You have WHS (Work Health and Safety) obligations to ensure a safe work environment for all trades and visitors. This includes clear site access, adequate lighting, safe scaffolding/ladders for roof work (solar HWS), and managing risks associated with plumbing, electrical, and gas installations. Ensure trades have their relevant SWMS (Safe Work Method Statements) for high-risk activities.

5. Practical Considerations for Kit Homes

Building with a steel frame kit home offers specific advantages and considerations concerning HWS installation.

5.1. TRUECORE® Steel and BlueScope Products

Many Australian steel kit homes utilise light gauge steel framing manufactured from TRUECORE® steel, an innovative product from BlueScope. This material offers:

• Termite Resistance: No need for chemical pest treatments, which is great for health and the environment.
• Strength and Durability: Steel frames are incredibly robust and consistent. This provides a stable platform for attaching systems like HWS. For roof-mounted solar HWS, the strength of a professionally engineered steel truss system provides excellent support.
• Precision: Steel framing is fabricated with high precision, meaning straighter walls and more accurate dimensions, which can simplify pipe run planning.
• Corrosion Protection: TRUECORE® steel is manufactured with a metallic hot-dipped coating, typically Zinc/Aluminium alloy, providing excellent corrosion resistance. However, it's still prudent to ensure no direct long-term contact between dissimilar metals in a moist environment (e.g., copper pipes touching steel frame directly without protection), although modern building practices and standards (AS/NZS 3500) prevent such issues. Use appropriate grommets for pipe penetrations through steel studs to protect both the pipe and the stud coating.

5.2. Integration with Build Schedule

• Rough-in: Plumbing rough-in (pipes within walls) needs to happen after the steel frame is erected but before sarking and external cladding or internal linings. Ensure your plumber understands the steel frame construction and how to make penetrations without compromising the structure. Your kit home supplier can guide on this.
• External vs. Internal Units: Decide early if your HWS will be internal or external. External units require specific pre-planning for concrete slabs, weather protection shrouds, and external pipe runs. Internal units require dedicated cupboard space or a utility room, ventilation (for gas), and specific floor drainage trays for storage tanks.
• Slab Penetrations: Planning for pipe penetrations through the concrete slab (if your kit home has one) is critical. These must be accurately located during the slab pour phase to avoid costly rework.

5.3. Insulation and Energy Efficiency for Kit Homes

Steel frames, while excellent structurally, perform differently thermally from timber. Steel conducts heat more readily. Therefore, insulation is even more critical for energy efficiency.

• Pipe Lagging: NCC J5D4 requires hot water pipes to be insulated. For steel framed homes, ensure all exposed hot water pipes, particularly those external or in unconditioned spaces (like roof cavities or subfloors), are thoroughly lagged with appropriate insulation. This includes the first metre of cold pipe leading into the HWS to reduce heat creep.
• Wall Cavity Insulation: Ensure the walls of your kit home are well insulated, as per NCC Volume Two, Part 3.12. This will help maintain stable indoor temperatures and reduce demand on heating systems, indirectly benefiting HWS efficiency.
• Tank Insulation: Opt for HWS with high insulation ratings for their storage tanks to minimise standby heat losses. Consider insulating the tank itself further with an HWS blanket, especially in colder climates.

6. Cost and Timeline Expectations

Understanding the financial and time commitments is vital for owner-builders.

6.1. Cost Estimates (AUD) - 2024 Indicative Prices

These are estimates and can vary significantly based on brand, installation complexity, location, and the specific tradesperson.

*Annual Running Costs are highly variable by location, energy prices, usage habits, and system efficiency. Use these as a very broad guide.

Additional Costs to Consider:

• Gas Line Connection: If connecting to natural gas for the first time, this can cost $1,000 - $5,000+, depending on distance to mains.
• Electrical Upgrades: Very high-power electric instantaneous units may require an electrical service upgrade, costing several hundred to several thousand dollars.
• Building Permit/Council Fees: May include specific plumbing or building permit fees for the HWS installation, especially for solar or heat pumps.
• Cranes/Specialised Equipment: For large, heavy solar tanks or roof-mounted systems on two-story homes, a crane might be needed, adding $500 - $1,500.

6.2. Timeline Expectations

• Research & Selection: 2-4 weeks (crucial for accurate decision-making).
• Quoting & Ordering: 1-3 weeks (allowing for multiple quotes and lead times for specific units).
• Permit Application: 2-6 weeks (varies by council and complexity).
• Rough-in Plumbing: Generally integrated into the overall plumbing rough-in phase of the build, which takes 1-2 weeks.
• Final Installation & Commissioning: 1-3 days (once the unit is on site and services are available).
• Inspections: Schedule per council requirements; typically within 1-2 weeks of completion.

Owner-Builder Tip: Plan your HWS decision and placement early in the design phase. Retrofitting later is always more expensive and complicated. Coordinate your plumber and electrician/gas fitter to work concurrently or sequentially to minimise delays.

7. Common Mistakes to Avoid

Even experienced builders can make errors; for owner-builders, the learning curve is steeper. Here are common HWS mistakes for your kit home project:

1. Underestimating Hot Water Demand: Choosing a tank too small or an instantaneous unit with insufficient flow rate leads to cold showers and frustration. Always over-estimate slightly rather than under-estimate.
2. Ignoring Energy Efficiency: Going for the cheapest upfront system without considering long-term running costs is a false economy. An inefficient HWS can add hundreds, if not thousands, to your annual utility bills over its lifespan.
3. Incorrect Placement: Locating the HWS too far from main usage points, outdoors in a very cold climate without adequate protection, or without sufficient clearances for servicing and ventilation can cause inefficiencies, higher running costs, maintenance issues, and non-compliance.
4. Neglecting Regulatory Compliance (NCC & Standards): Failing to engage licensed trades, not obtaining permits, or skipping required safety devices (tempering valves, TPR valves, correct flueing) is illegal, unsafe, and will prevent you from getting occupancy certificates or insurance in case of an incident. This is the biggest and costliest mistake.
5. Poor Pipe Insulation: Skimping on pipe lagging, especially in a steel frame home where thermal bridging can occur, leads to significant heat loss and wasted energy. Insulate all hot water pipes as per NCC and AS/NZS 3500.4.
6. Inadequate Structural Support: Placing a heavy storage tank on an unreinforced floor or mounting solar collectors on a roof not designed for the load can lead to structural failure, which is incredibly dangerous and costly to remediate. Always consult your kit home structural engineer.
7. Ignoring Water Quality: Hard water areas can cause scale build-up in HWS, reducing efficiency and lifespan. Consider water softeners or specific HWS types designed for such conditions. A plumber can advise on this.
8. Not Leveraging Rebates: Missing out on government rebates (STCs, state-specific incentives) for energy-efficient systems like heat pumps or solar HWS. These can significantly offset the higher upfront cost.

8. When to Seek Professional Help

As an owner-builder, you're the project manager, but certain tasks must be performed by licensed professionals. Never compromise on this for safety, compliance, and warranty reasons.

• Licensed Plumber: ABSOLUTELY ESSENTIAL for all hot water system installations, connections to water supply, installation of tempering valves, relief valves, and drainage. They ensure compliance with NCC Volume Three and AS/NZS 3500.4. Also required for gas connections if they hold a gas fitter's license.
• Licensed Electrician: CRITICAL for all electrical wiring, connections, circuit protection (RCDs), and earthing of electric, heat pump, and boosted solar hot water systems. They ensure compliance with AS/NZS 3000.
• Licensed Gasfitter: If your HWS runs on natural gas or LPG, a licensed gasfitter (often the plumber, but check their licence) is non-negotiable for system connection, testing, flueing, and ventilation compliance with AS/NZS 5601.1.
• Structural Engineer: MANDATORY: For verifying the suitability of your steel frame's roof or flooring to support heavy HWS components (e.g., roof-mounted solar collectors, large storage tanks). Your kit home supplier's engineer can often provide this advice or connect you with one.
• Building Certifier/Surveyor: You'll engage this professional to oversee your entire build's compliance with the NCC and local regulations. They will inspect the HWS installation as part of their approval process.
• Energy Assessor: For comprehensive advice on optimising your home's thermal performance, including HWS, to meet NCC energy efficiency requirements and achieve a good Star Rating.

Owner-Builder Pro-Tip: Don't just get quotes; interview your trades. Ask them about their specific experience with steel frame construction, their understanding of the NCC and relevant AS/NZS standards, and their proposed installation plan. A good trade will be happy to explain their process and provide their license details.

9. Checklists and Resources

9.1. Hot Water System Selection Checklist

• Number of occupants and usage assessment completed.
• Energy sources available (electricity, natural gas, LPG, solar access) confirmed.
• Climate considerations factored in (cold weather protection, solar gain).
• Upfront cost budget set.
• Running cost expectations understood.
• Required tank size or flow rate determined.
• Preferred HWS type chosen (Electric Storage, Gas Instantaneous, Heat Pump, Solar).
• Space requirements for selected HWS type (indoor/outdoor, clearances) confirmed.
• Structural support requirements (slab, roof) for selected HWS confirmed with engineer/kit home supplier.
• Potential government rebates (STCs, state-specific) researched.
• Reviewed kit home plans for HWS integration points.

9.2. Installation Planning & Compliance Checklist

• Local council and state regulatory body requirements checked.
• Necessary permits obtained.
• Licensed Plumber engaged and verified.
• Licensed Electrician engaged and verified.
• Licensed Gas Fitter engaged and verified (if applicable).
• HWS placement maximises efficiency (close to outlets).
• Clearances for servicing, ventilation, flueing confirmed.
• Drainage for relief valves planned and compliant with AS/NZS 3500.4.
• Piping material and sizing confirmed by plumber.
• All hot water pipes (and first metre of cold) planned for insulation (lagging).
• Tempering valve installation specified to limit water to 50°C.
• All penetrations through steel frame protected with grommets.
• Commissioning process with trades understood.
• All compliance certificates (Plumbing, Electrical, Gas) requested upon completion.
• Site WHS plan includes HWS installation risks.

9.3. Useful Resources

• National Construction Code (NCC): https://ncc.abcb.gov.au/ (Access requires free registration)
• Your State's Plumbing Regulator:
  • NSW: NSW Fair Trading (https://www.fairtrading.nsw.gov.au/)
  • VIC: Victorian Building Authority (https://vba.vic.gov.au/)
  • QLD: Queensland Building and Construction Commission (https://www.qbcc.qld.gov.au/)
  • WA: Department of Mines, Industry Regulation and Safety (https://www.dmirs.wa.gov.au/)
  • SA: Office of the Technical Regulator (https://www.sa.gov.au/topics/energy-and-mining/technical-regulation/plumbing-gas-and-electrical)
  • TAS: Consumer, Building and Occupational Services (https://www.cbos.tas.gov.au/)
• Australian Building Codes Board (ABCB): https://www.abcb.gov.au/
• Clean Energy Regulator (STC information): https://www.cleanenergyregulator.gov.au/
• Energy.gov.au (Government energy efficiency advice): https://www.energy.gov.au/
• Work Health and Safety Regulator in your state:
  • SafeWork NSW: https://www.safework.nsw.gov.au/
  • WorkSafe Victoria: https://www.worksafe.vic.gov.au/
  • WorkSafe Queensland: https://www.worksafe.qld.gov.au/
  • WorkSafe WA: https://www.commerce.wa.gov.au/worksafe
  • SafeWork SA: https://www.safework.sa.gov.au/
  • WorkSafe Tasmania: https://www.worksafe.tas.gov.au/

10. Key Takeaways

Choosing and installing a hot water system for your steel frame kit home is a significant decision impacting your daily comfort, running costs, and home’s value. Prioritise safety and compliance above all else by engaging licensed professionals for all plumbing, electrical, and gas work. Understand your hot water usage, environmental context, and energy options thoroughly before making a selection. Leverage the benefits of steel framing by carefully planning penetrations and ensuring adequate structural support for heavy units. Embrace energy-efficient options like heat pumps or solar where feasible, taking advantage of available government rebates. Plan early, communicate clearly with your trades, and meticulously adhere to NCC requirements and Australian Standards to ensure a successful, safe, and efficient hot water system for your new home. Your diligence in this crucial stage will contribute immensely to the comfort and longevity of your owner-built steel kit home.