Steel Frame Garden Building or Timber: Which Is Better for Your Next Build?

When planning a new garden building, whether it’s a garage, extension, garden office or full home, one of the first big decisions you’ll face is what type of structural frame to use.

The two most common options? Steel frame and timber frame.

Both have their strengths, and choosing the right one depends on your budget, building size, location and long-term goals. In this guide, we’ll break down the pros and cons of steel and timber framing to help you decide what’s best for your garden building.

What Is a Steel Frame Garden Building?

Steel-framed garden buildings use columns, beams, and joists, which are often made from coated galvanised steel, to create a rigid, load-bearing yet lightweight structure.

Pros of using a steel framework:

• Incredible strength – Ideal for long spans, large openings and tall structures
• Fire and pest resistant – Doesn’t burn, rot or get eaten by garden pests
• Minimal maintenance – No warping, shrinking or twisting
• Prefabricated options – Faster on-site assembly and less waste
• Ideal for harsh environments – Withstands wind, moisture and weather extremes

Cons of Steel Framing:

• Higher upfront cost – Especially compared to timber for smaller builds
• Thermal bridging – Needs careful insulation to reduce heat loss
• Heavier foundations – May require reinforced footings

What Is Timber Frame Construction?

Timber-framed buildings use structural-grade wood, such as softwood studs, beams, and joists, as the main load-bearing skeleton. It's a traditional and often go-to choice for residential and smaller-scale projects.

Pros of Timber Frame:

• Cost-effective – Lower initial material and labour costs
• Straightforward to work with – Great for DIYers or local builders
• Thermal performance – Wood is a natural insulator
• Renewable and eco-friendly – When sourced responsibly
• Flexible for small custom builds

Cons of Timber Frame:

• Vulnerable to moisture and pests – Requires treatment and protection
• Less durable over time – Can warp, rot or shrink
• Higher fire risk – Compared to non-combustible steel
• Less suited for very large or complex buildings

Which One Should You Choose?

Choose a steel frame garden building if:

• You’re building a garden office or small-to-medium sized structure
• There will be electrical goods in operation or installed inside
• You want maximum durability with minimal maintenance
• You need a fast build time using prefabricated kits
• Fire or pest resistance is a priority

Choose timber if:

• You’re building a small shed or storage locker
• Budget is a key factor
• You’re aiming for a short-term or the DIY-friendliest approach
• You prefer more natural thermal performance

Can we help you?

Both steel and timber have earned their place in modern construction. Your choice should come down to what suits your project best in terms of size, budget, intended use and longevity.

Still not sure which frame to go with? Contact the team at PermaRoom for expert advice on materials, kits, and construction options, whether you’re looking for a fully designed and managed project or an off-the-shelf steel framed garden building to erect yourself - we’ll help you build smarter from the ground up.

Need Supplies for Your Framed Building?

Browse our range of ready-to-go steel framed garden buildings here or give us a call to find out more about bespoke design at PermaRoom. The possibilities are endless, download a brochure.