Making your home more energy-efficient starts with one of the most important pieces of the puzzle: insulation. The right insulation keeps you warm in winter and cool in summer, all while lowering your energy bills and reducing your environmental impact. But there’s more to it—insulation can also affects your indoor air quality, sound levels, and even fire safety.

In this guide, you’ll learn about the different types of insulation, including eco-friendly, fire-resistant, and acoustic options. We’ll also cover how to choose the right insulation for your walls, ceiling, and floor, and share some handy tips for installation to make sure you get the best results.

Why Insulation Matters for Your Home

Insulation isn’t just about keeping the temperature comfortable—it helps your entire home work more efficiently. With good insulation, you’ll enjoy:

• Lower energy bills

• A smaller carbon footprint, and

• Better soundproofing

If you plan to design a sustainable house or renovation, incorporating the right insulation is an essential ingredient for energy efficiency.

How does insulation work?

Bulky types of insulation, like batts and polystyrene, work by trapping air into millions of tiny air pockets. The trapped air inhibits the transfer of heat out of the house in cold weather or into the house in warm weather.

Types of Insulation You Can Use

There are several types of insulation, each suited to different parts of your home. Here’s a quick rundown:

Batt and Roll (Blanket) Insulation

Made from: Fibreglass, mineral wool, natural wool, or cotton

Great for: Walls, ceilings, and underfloors

Good to know: It’s cost-effective and relatively easy to install yourself. Just be careful to make sure it’s installed properly or it won’t work as well as it should (more on installation below).

Loose-Fill and Blown-In Insulation

Made from: Cellulose (recycled paper), fibreglass, or mineral wool

Great for: Filling tricky spaces, especially in older homes

Good to know: It settles over time, so make sure it’s properly packed to avoid gaps.

Spray Foam Insulation

Made from: Polyurethane

Great for: Sealing cracks and gaps

Good to know: It’s super effective but can release VOCs and is hard to recycle.

Rigid Foam Boards

Made from: Polystyrene or polyisocyanurate

Great for: Floors and walls where space is limited

Good to know: It’s durable and moisture-resistant but comes with a higher carbon footprint.

Reflective or Radiant Barriers

Made from: Foil-faced materials

Great for: Hot climates

Good to know: works by reflecting heat rather than absorbing it and needs open air space to be effective.

Eco-Friendly Insulation Options

If you care about the planet (and your health), you’ll want insulation that’s non-toxic, sustainably made, and either recyclable or biodegradable. Here are some of the best green choices:

Sheep’s Wool

What it is: 100% natural wool

Why it’s great: Absorbs indoor air pollutants and helps regulate humidity

Hemp and Cork

What they are: Fast-growing plants turned into insulation

Why they’re great: Natural resistance to pests and mould, plus they’re carbon-negative during production

Tip: Look for certifications like GECA, Global GreenTag, or Declare to make sure you’re getting a healthy and sustainable product.

Cellulose

What it is: Recycled newspapers treated for fire and pest resistance

Why it’s great: Low environmental impact, safe for your home, and biodegradable

Cotton/Denim

What it is: Recycled jeans and other cotton fibres

Why it’s great: Safe to touch, good sound absorber, and low-impact to produce
Acoustic Insulation for a Quieter Home
Want to block out street noise, loud neighbours, or keep your home theatre quiet? Acoustic insulation is your friend.

Acoustic insulation for soundproofing your home

Acoustic insulation reduces the transmission of sound from one space to another. It works in a few ways:

• Absorption: Materials like mineral wool or acoustic foam soak up sound waves, especially mid and high frequencies, keeping echoes and reverberations down.

• Damping: This reduces vibrations that travel through solid structures, like walls or floors. Think of it like cushioning sound so it loses energy.

• Decoupling: By physically separating layers (like using resilient channels or double walls), sound vibrations can’t pass through as easily.

• Mass: The heavier the barrier (like a thick wall or dense insulation), the harder it is for sound to get through.

Using acoustic insulation will give you more peace, quiet, sleep and privacy by reducing noise like traffic neighbours and your kid’s drum kit as well as improve your sleep and your focus when working. It also improves privacy by restricting conversations travelling through walls.

Fire-Resistant Insulation for Peace of Mind

Fire-safe insulation can slow down the spread of flames, giving you more time to react in an emergency.

Top Fire-Safe Choices

• Rock Wool/Mineral Wool: Naturally fireproof and handles very high heat

• Fibreglass: Won’t burn, though some binders may

• Cellulose (Treated): Fire retardants are added for safety

Always check the insulation is tested to local standards to ensure maximum fire safety.

Choosing Insulation for Each Area of Your Home

Each part of your home has different needs. Here’s what to keep in mind:

Walls

• Use batts or blown-in options

• Look for R-values between R2.0–R3.2, depending on your climate zone

Ceilings and Roofs

• Go for higher R-values here— the National Construction Code (Australia) specifies minimums which you can always exceed. In Australia the is minimum is between R4 and R7 depending on your climate zone

• Use batts, loose-fill, or even reflective barriers in hot regions

Underfloors

• Use rigid foam or foil-backed batts

• Aim for R1.0–R2.0 in most areas

• Watch for moisture and airflow in suspended floors

Tip: Check your climate zone using the NCC Climate Zone Map: ncc.abcb.gov.au

Indoor Air Quality: What to Watch Out For

Insulation touches almost every part of your home, so you want it to be as safe as possible.

Avoid

• Products with formaldehyde-based binders

• High levels of VOCs

Choose

• Natural or low-VOC options like wool, hemp, and cellulose

• Products with GreenGuard or GECA certifications

Bonus: Natural insulations like wool and cork can actually help filter indoor air.

How It’s Made (And How It Ends)

Eco-conscious choices go beyond the material itself. Think about how it’s made and what happens when it’s removed years later.

Production Footprint

High-impact: Spray foams, rigid foams

Medium: Fibreglass (unless made from recycled glass)

Low: Cellulose, wool, hemp, cork

End-of-Life Options

Recyclable: Cellulose, cotton, cork

Reusable: Some batts and boards if kept dry

Landfill: Spray foams, glued rigid boards

Look for products with Environmental Product Declarations (EPDs) to compare options more easily.

Installation Tips: Getting the Most from Your Insulation

How insulation is installed plays a huge role in how well it performs. Even the best materials won’t be effective if there are gaps, poor seals, or incorrect placement. A small crack around a light switch or missed section in an attic can lead to drafts, heat loss, or sound leaks. It’s also crucial not to compress insulation during installation, as squashing it reduces its ability to trap air—one of the key factors that makes it effective at slowing heat transfer and blocking sound. That’s why it’s sometimes smart to call in a pro—especially for tricky areas like crawl spaces, vaulted ceilings, or older homes with irregular framing. Professionals know how to install insulation tightly and evenly, spot problem areas, and make sure your home stays energy-efficient, comfortable, and quiet. Getting it right the first time saves you money and hassle down the line.

Airtightness for an energy efficient home

Creating an airtight thermal envelope provides a protective shell for your home and includes insulation, an air barrier, and everything that separates inside from out. When this envelope is airtight, your insulation works more effectively because it’s not being bypassed by moving air. When this envelope is airtight, your insulation works more effectively because it’s not being bypassed by moving air. Even if your walls, roofs and floors have high-quality insulation, air leaks—like gaps around windows, doors, outlets, or plumbing—can let heat and sound sneak in or out, undermining the whole system. 

House wraps or air barrier membranes are breathable, protective layers that go on the exterior of your home (under the cladding) to block drafts and moisture, while still allowing trapped humidity to escape. When properly sealed, house wrap helps create an airtight envelope. The result? A home that stays more energy-efficient, comfortable, and resistant to mold, moisture, and noise—year-round.

Wrapping Up

Choosing the right insulation can make your home more comfortable, quieter, safer, and better for the planet. With so many options—from eco-friendly wool and cellulose to fire-safe and sound-blocking mineral wool—you can tailor your insulation to fit your exact needs.
Just remember: the best insulation is only as good as the installation. Take the time to plan, seal, and follow best practices, and you’ll enjoy the benefits for decades.