How To Insulate Your Shed To Protect It From Fire Hazards

The backyard shed is many things to many people. If you’re a green thumb, it’s where you keep all your gardening paraphernalia, from pitchforks to potting mix. If you’re a handyman, it’s where you work on your latest project, whether it’s repairing a broken chair or building a model from scratch. And, if you’re like many blokes these days, your shed often serves as your man-cave, where you retreat from the world and potter or watch footy with your mates.

Whatever you use your shed for, if you want to make it more habitable, particularly in climates where extremes of heat or cold are common, then it can be a good idea to insulate your shed (just as you would your home). Insulation retains heat in winter and repels it in summer, as well as acting as good soundproofing material. But just as you would in your home, you need to use an insulation material that is fire resistant, particularly if you live in an area prone to bushfires. This guide looks at the common kinds of fires and types of fire resistant insulation you can choose from, so you know how to best protect your shed from the threat of fire.

The different classes of fire

Fire manifests itself in several different forms according to the Australian system of classification, including;

Class A fires – Those involving carbon-based solids such as wood, paper, cloth, rubber, plastics, grass and coal.

Class B fires – Those involving flammable and combustible liquids such as petrol, kerosene, oil, tar, paint and wax.

Class C fires – Those involving combustible gases such as LPG, butane, propane, natural gas and acetylene.

Class D fires – Those involving combustible metals such as sodium, potassium, magnesium and aluminium.

Class E fires – Those involving electrically energised equipment.

Class F fires – Those involving cooking oils and fats.

With each different class of fire, there is a different method required for extinguishing it. You should equip your shed with the appropriate extinguisher for the kinds of fires you are most likely to encounter. The types of fire extinguishers available include;

Water - Suitable for Class A fires.

Foam - Suitable for Class A and Class B fires.

Powder - Suitable for Class A, Class B, Class C and Class E fires.

Carbon dioxide  - Suitable for Class E fires.

Vaporising liquid - Suitable for Class A and Class E fires.

Dry chemical – Suitable for Class D fires.

Wet chemical - Suitable for Class F fires.

If you are not sure what type of fire you are most likely to encounter, it may be best to opt for a Dry Chemical Powder extinguisher, which is suitable for use on most types of household fires. It should be located near the entrance to your shed so that it is easily accessible in a fire emergency.

Ways in which fire can spread

Each class of fire behaves in a different way in regards to the strength and speed at which it spreads. Ways in which fire can spread include;

Conduction - When heat passes through various materials and ignites other materials beyond them (known as heat transmission).

Convection – Heat transmission by liquids and gases which expand and rise, spreading embers upwards.

Radiation - The transmission of heat by waves travelling through the air and being absorbed by other objects.

Direct burning – Direct application of fire from one object to the next (the simplest way fire is spread).

Fire resistant insulation types

So, given that you want to insulate your shed and also keep it safe from fire, let’s look at some of the types of fire-resistant insulation available on the market today.

Fibreglass insulation – This is often used to insulate buildings, as it is a non-combustible material (it melts rather than burns under extreme heat).

Stone wool insulation - Made from volcanic rock fibres which are also non-combustible. It will not fuel or spread a fire and does not emit toxic gases.

Sheep’s wool insulation - Does not support combustion and will extinguish itself in the event of fire, as wool fibre requires more oxygen than is available in the air to become flammable.

PIR insulation - Rigid foam insulation faced on one or both sides with a reflective foil laminate (which has both excellent fire and moisture absorption properties).

A further layer of protection

Once you have chosen and installed your insulation, many people choose to cover it with gypsum board (sheetrock), which is relatively inexpensive and contains fire resistant properties. The exterior of your shed should aso ideally be covered in steel sheeting, which will provide an additional barrier against fire.

Unlike wood, steel is non-combustible and does not release smoke, carbon dioxide, or VOCs (Volatile Organic Compounds) in the event of a fire. If you are lucky enough to own a steel shed, you already have a structure that is significantly fire-resistant. But if your shed is made from wood, you can improve its fire resistance by adding metal wall and roof sheeting to the exterior.

A supplier such as Titan Lite carries a comprehensive range of shed parts which can be ordered online and delivered onsite, including;

• QDEK Metal Wall and Roof Sheeting – Available in standard straight-cut lengths which are lightweight, weather and fire resistant and can be easily installed through fixing and notching of flashings.
• VDEK Metal Wall and Facia Sheeting – Available in standard straight-cut lengths which are installed using fixed screws.

Fire prevention tips

Now that you have a fully insulated shed which provides an effective deterrent to fire, these tips can help you keep your shed even safer, particularly if you live in a fire prone area such as the Australian bush.

• Make sure you fill in and cover all gaps in your shed where fire could enter or embers could lodge and burn.
• If your shed has gutters, cover them with gutter guards to prevent dead leaves and debris from accumulating in them.
• Regularly mow long grass around your shed and clear away fallen tree branches and other potential fuel.
• Don’t store combustibles in your shed such as petrol or gas cylinders.
• Install metal fly screens on your shed’s windows and vents to keep sparks and embers out.

Keeping your shed fire safe

Hopefully this guide has shown that it is possible to have a fully insulated shed that is also relatively fire safe, as long as you;

• Choose the right insulation
• Purchase the right fire extinguisher
• Clad it with the right materials and
• Keep the area around it free from potential fuel.

So whether you use your shed as a workshop or a place to store valuables, it will always be there at the end of the pat - sturdy, inviting and as fire safe as it can possibly be.