Metal Shed Insulation – What Type of Insulation Is Best?

Insulating metal sheds is crucial, whether it serves as an office or workshop. Not only does it ensure better heat retention during colder months, but also an efficient transfer of the sun’s warmth during summer. But finding the perfect insulation can be a challenge. With numerous factors to consider, making the right choice becomes essential.

This article is designed to provide you with all the basics about metal shed insulation.

Determining the Necessity of Metal Shed Insulation

Telluria Eleganto Heavy Duty Steel Shed
Telluria Eleganto Heavy Duty Steel Shed

Insulation is not always required for every metal shed. Its necessity depends on the climate, location, and the shed’s purpose.

One crucial consideration is the climate in which your shed is situated. If you live in an area with high humidity and temperature swings, condensation arises. Without proper insulation, moisture can accumulate inside the shed. This, in return, can lead to problems like rust, corrosion, and damage to stored items due to mould and mildew. Insulation helps stabilise the interior temperature, preventing condensation and its associated risks.

The purpose of your metal shed also plays a role in determining the need for insulation. If you use the shed as a space, e.g. office or workshop, where temperature control is crucial, insulation is a must. It helps maintain stable temperatures year-round so that you can work in convenience.

Ultimately, the decision to insulate your metal shed depends on your specific circumstances. You may consult professionals to check your status and make an informed choice.

Achieving Temperature Stability and Moisture Prevention

Telluria Eleganto Heavy Duty Steel Shed
Telluria Eleganto Heavy Duty Steel Shed

Insulating metal sheds serves two essential purposes:

  • stabilising the interior temperature
  • preventing moisture infiltration through condensation

Insulation is installed over the framing of the building for continuous coverage. This seamless insulation layer acts as a barrier, preventing energy and moisture transfer.

By providing insulation over the framing, temperature stability is achieved. It helps regulate the internal climate, minimising the impact of external temperature fluctuations. 

During winter, it acts as a barrier that slows down the movement of heat. This method ensures better thermal retention within the building. Conversely, in summer, it serves as a shield. It keeps the heat outside and maintains a cooler interior environment. A more comfortable environment inside the shed awaits! 

And by preventing condensation, insulation safeguards the structure from damage, e.g. rust. Overall, insulating a metal shed ensures optimal performance and durability. Plus, protection, especially for your valuable assets stored within the shed.

Types of Metal Building Insulation

There are several types of insulation commonly used for metal buildings. Let’s explore each type, how they work, their installation methods, and their pros and cons.

1. Spray foam insulation

Spray foam insulation

(Image Credit: Wikimedia Commons)

How it works: Spray foam insulation comprises two liquid components that mix and expand. This creates a foam that adheres to surfaces. It provides an airtight seal, effectively blocking heat transfer.

Installation: This type of insulation is typically installed by professionals using specialised equipment. The foam is sprayed onto the surfaces, expanding and adhering to create a seamless layer.

Pros: Spray foam insulation offers excellent thermal performance and air-sealing capabilities. It can fill gaps and cavities, providing comprehensive coverage. It also acts as a vapour barrier, preventing moisture intrusion.

Cons: Professional installation is required, making it more expensive than other insulation options. Improper installation may lead to poor performance. It can be challenging to modify or repair once applied.

2. Rigid board insulation

Rigid board insulation

(Image Credit: Flickr)

How it works: Rigid board insulation is made of foam panels with high insulating value. It offers thermal resistance by reducing heat conduction through the building envelope.

Installation: It’s cut to size and installed between the framing members. Or it can be applied directly to the exterior walls or roof.

Pros: Rigid board insulation provides excellent insulation value and durability. Its high compressive strength makes it suitable for areas that require load-bearing support. It’s resistant to moisture and provides good sound insulation, to add.

Cons: It can be more expensive than other insulation types. Installation may also require extra steps to maintain its effectiveness. This can be sealing joints and edges. It’s also rigid and may be challenging to install on irregular or curved surfaces.

3. Loose-fill insulation

Loose-fill insulation

(Image Credit: Degnan)

How it works: Loose-fill insulation consists of small particles, e.g. cellulose or mineral wool. These materials are blown or poured into the cavities or attic spaces. They then fill them to create a thermal barrier.

Installation: This type of insulation is typically installed using a blowing machine. It is blown into the desired areas, filling gaps and cavities evenly.

Pros: Highly effective in filling irregular spaces, gaps, and hard-to-reach areas. It provides excellent thermal resistance and can be added to existing insulation. It’s also resistant to moisture and settling.

Cons: Installation requires specialised equipment and expertise. Without proper installation and containment, loose fill insulation may settle over time. This can result in reduced effectiveness. It may also be more expensive than other insulation types.

4. Batt insulation

Batt insulation

(Image Credit: Flickr)

How it works: Batt insulation comes in pre-cut panels or rolls made of fibreglass. The panels are fitted between the framing members, providing a thermal barrier.

Installation: The pre-cut panels or rolls are placed between the framing members. This ensures a snug fit and avoids gaps.

Pros: Batt insulation is widely available, cost-effective, and offers good thermal performance. It can be easily installed by homeowners as a DIY project. It also provides sound absorption properties.

Cons: Improper installation with gaps or compression can reduce its effectiveness. It may not fit perfectly in irregular or non-standard spaces. In such a case, it’ll require additional trimming or adjustments.

5. Vapour barrier

Vapour barrier

(Image Credit: Wikimedia Commons)

How it works: A vapour barrier is a material that helps control moisture. It basically blocks the movement of water vapour.

Installation: Vapour barriers are installed during the construction or insulation process. They are placed on the interior side of the insulation, facing the conditioned space. Proper sealing of joints and overlaps is crucial to maintain its effectiveness.

Pros: Helps prevent moisture intrusion, reducing the risk of condensation, mould and rot. It aids in maintaining a healthy indoor environment. It also protects the integrity of the structure.

Cons: Improper installation or damage to the vapour barrier can compromise its effectiveness. In some cases, excessive use of vapour barriers can trap moisture.

The Dangers of Not Having Insulation

The idea of insulating your steel shed is an optional expense. However, leaving it uninsulated can come with potential dangers and drawbacks.

Insulation serves several critical purposes. Neglecting it can also have adverse effects on your belongings. Here are some of the key dangers of not having insulation in your garden building:

1. Temperature extremes

Metal garden sheds, by nature, are susceptible to extreme temperature fluctuations. Without insulation, one can become a metal box. It can quickly turn into an oven in the summer and a freezer in the winter.

These temperature extremes can cause damage to items stored inside. This can include delicate garden tools, equipment, and materials. For example, high temperatures can lead to deteriorating chemicals and materials. Meanwhile, freezing temperatures can damage sensitive electronics.

2. Condensation and moisture issues

Steel sheds are prone to condensation. When warm, moist air inside the structure meets the cold metal walls and roof. This, in return, can lead to condensation forming on these surfaces. And over time, this moisture can cause rust, mould, and mildew growth. Insulation helps regulate temperature and reduce condensation, preventing these issues.

3. Limited comfort

Do you intend to use your metal shed as a garden office? Perhaps a hobby room? Or a place to spend extended periods? If so, insulation is essential for creating a comfortable environment.

Without insulation, the shed can be unbearably hot or cold. This makes it difficult to work or spend time inside. However, proper insulation helps maintain a consistent and comfortable temperature. This allows you to make the most of your space year-round.

4. Increased energy costs

Do you use your metal shed building for any heating or cooling needs? Could it be for storing temperature-sensitive items or creating a comfortable workspace? Then having insulation can result in significantly higher energy bills.

Uninsulated means it will require more energy to maintain a comfortable temperature. This can be both costly and environmentally unfriendly in the long run.

5. Reduced lifespan of belongings

The lack of insulation can accelerate the wear and tear on items stored in your metal shed. Extreme temperatures and moisture issues can lead to the premature deterioration of belongings. Lucky for you, insulating your shed can help extend the lifespan of these items.

Insulation may add to the initial cost of setting up your metal shed. However, it provides numerous benefits that far outweigh the investment. It’s a crucial component in ensuring the safety and functionality of your metal storage shed.


The necessity of metal shed insulation varies based on factors like moisture concerns. With various insulation options available, choosing the best one requires careful evaluation.

We hope this guide has provided valuable insights to help you make an informed decision. Remember to prioritise optimised insulation for enhanced protection and comfort throughout the year.

Explore a variety of insulated garden rooms at Garden Buildings Direct. Don’t miss out on our steel garden rooms as well!

For your next read, head into: Why Metal Sheds Are a Smart Choice?

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