Skip to content Skip to footer

Entire site

How to insulate walls

View the video

Project Overview

Insulation in your walls reduces heating and cooling costs, and helps stop sound travelling between rooms. We’ll teach you how to trim insulation batts to size and install them between the joists in your wall cavity.
Continue to step-by-step instructions

Time Required

Done in a Day

Step by Step Instructions

Previous Next

1 Install insulation batts in the wall cavity

2 Trim the insulation to fill small gaps in the wall cavity

Step 1. Install insulation batts in the wall cavity

Before you start, switch off the electricity and make sure all your electrical cables are safely out of the way. Then push the batts between the wall studs. Make sure you fill every gap in the cavity of your wall.

Previous Step Next Step
Step 2. Trim the insulation to fill small gaps in the wall cavity

When you are insulating smaller spaces, measure the gap between the studs then trim your batt to size using a knife and a straight edge. Cut the batt slightly larger than the gap so it sits snugly in place. When the whole wall cavity is filled, you’re ready to put your wall up.

Previous Step Next Step

7
Suggested products from our range

Rhino 1.8m Single Sided Aluminium Step Ladder

^$79

DTA Australia 2400mm Tile Straight Edge

^$67^.98

Protector Nuisance Disposable Dust Masks - 10 Pack

^$2^.90

Protector Ultralite Clear Wraparound Safety Glasses

^$4^.30

Craftright Leather Riggers Gloves

^$7^.90

Trojan Retracting Safety Knife

^$11^.98

Earthwool R-2.5HD 90 x 580mm 9.42m2 Wall Acoustic And Thermal Insulation Batts - 14 Pack

^$76^.50

See all 7 suggested products

More D.I.Y Advice

living room

Heating & Cooling How to cool your house naturally With summer just around the corner, it’s time to start thinking about how to keep cool and comfortable. The good news is there are lots of smart ways to keep your home cool.

Pet doors

Heating & Cooling How to create an airtight home To have an airtight home, you’ll need to prevent airflow leaving your home. We’ll show you some places which may leak air and what you’ll need to do to reduce it.

Man in protective gear removing insulation

Heating & Cooling How to remove insulation Everything you need to know about removing fibreglass insulation.

save energy

How To Save Energy & Electricity How to save energy around the home We lift the lid on where you can save the most energy in your home, no matter who you are or where you live. These simple changes will help to reduce energy costs and keep your home comfortable all year.

Man installing pleated foil insulation

Heating & Cooling How to install underfloor foil insulation Insulating your home is a great way to save money on heating and cooling costs. Learn how easy it is to install foil insulation in your subfloor.

Woman filling small gaps with insulation

Heating & Cooling How to insulate walls Installing insulation in your walls is a great way to increase energy efficiency and reduce noise. Learn how easy it is to do yourself.

Material for insulating your ceiling

Heating & Cooling How to insulate a ceiling Keep your home warmer in winter and cooler in summer by insulating your ceilings. We’ll show you all you need to know about installing ceiling insulation.

Trim Special Shapes

Heating & Cooling How to install polystyrene insulation Save money on your energy bills by insulating your home. See how simple it is to do the job yourself.

Choose wall colour with colour wheel

Walls How to create a feature wall A feature wall will add interest and create a focal point for your room. Here are some tips to help you create a feature wall in your home.

Timber looks feature wall

Walls D.I.Y. timber-look feature wall Learn how to create a timber-look feature wall in your home

picture frames

Walls How to hang paintings and picture frames Hanging a picture accurately and safely can be a tricky job. But with our picture hanging guide you’ll never hang a picture in the wrong spot again.

Person mixing the wallpaper paste

Walls How to hang wallpaper New wallpaper can transform a room and also cover up any imperfections in a wall. We’ll show you how easy hanging wallpaper can be when you know how.

Apply second coat of plaster to repair hole in wall

Walls How to fix a hole in a plaster wall Repairing holes in walls is a cost effective D.I.Y. job. Learn the basic steps for fixing a hole in a plaster wall.

Person cutting off the skirting boards

Walls How to install skirting boards This video shows you how to measure, cut and install skirting boards in your home.

Laying the next courses of bricks

Walls How to build a brick wall The art of laying bricks is a good skill to learn if you want to take your D.I.Y. to the next level. We’ll show you what’s involved in building a brick wall.

Man applying the finish to the wall

Walls How to apply a top coat to render We’ll show you how applying a top coat to your render is a great way to protect the surface of your walls and keep them looking new for longer.

front yard raised timber garden bed

Planning & Projects How to give your front garden a D.I.Y. makeover With some simple D.I.Y. skills, you can transform your front yard into something special that will improve your home’s street appeal.

Master bedroom makeover

Bedroom Refresh your master bedroom We’ll show you how easy is to transform your master bedroom into a contemporary masterpiece.

diy playground backyard

Outdoor Living How to build a D.I.Y. outdoor playground Transform an unused corner of your backyard into a fun children’s playground.

Landscaping for any size backyard

Paths & Landscaping Landscaping for any size backyard Here are some simple D.I.Y. landscaping ideas to make a great outdoor space.

petunia

Planting & Growing What to plant in spring Say goodbye to cold winter days and hello to the sun and warmth of spring. Now is the perfect time to get in the garden and start planting. But what to plant? Our spring planting guide has the answers.

modern white open plan kitchen

Ideas & Makeovers How to renovate and modernise your kitchen Watch how we renovate an old 70s kitchen and give it a stylish D.I.Y. makeover that suits modern living.

kaboodle kitchen outdoors

Benchtops & Cabinets What to consider when installing an outdoor Kaboodle kitchen A kitchen is a great way to spruce up your outdoor living and entertaining areas. The team at Kaboodle share a few hints and tips on what to consider when designing your very own outdoor kitchen using their products.

D.I.Y. copper clothes rail

Bedroom D.I.Y. copper clothes rail Create more space in your wardrobe with this easy-to-make industrial copper clothes rail.

Health & Safety

Please make sure you use all equipment appropriately and safely when following the advice in these D.I.Y. videos. You need to be familiar with how to use equipment safely and follow the instructions that came with the equipment. If you are unsure, you may feel it is safest to consult an expert, such as the manufacturer or an expert Bunnings Team Member.

Grave health hazards are linked to asbestos, which may be in homes built up to 1990. Health hazards may result from exposure to lead-based paints in older materials and copper chromium arsenic (CCA) treated timber. For information on the dangers of asbestos, lead-based paint and CCA treated timber and tips for dealing with these materials contact your local council's Environmental Health Officer or visit our Health & Safety page. You can also use a simple test kit from Bunnings to indicate the presence of lead-based paint Test.

Top of the content

Top of the content

Please enable JavaScript to enhance your experience on the Bunnings site. We have detected that JavaScript has been disabled in your browser. Please enable JavaScript in your browser settings to enhance your experience.