Property Types in the UK: What Every Homeowner Should Know

If you’re planning a project, the first step is to know which property type you’re dealing with. A new build, a house extension, a loft conversion, or a garden room each comes with its own rules, costs, and design tricks. Knowing the basics saves time, money, and a lot of headaches.

New Build vs. Extension: The Core Differences

A new build is a stand‑alone house that starts from the ground up. You’ll need a full planning application unless the site falls under permitted development for small structures. This route gives you total control over layout, materials, and energy standards, but it also means higher upfront costs and a longer timeline.

An extension adds space to an existing home. In the UK, many extensions qualify for permitted development, meaning you can often avoid a full planning submission if you stay within size limits (usually up to 4 m for rear extensions and 3 m for side extensions). Extensions are great for adding a conservatory, garden room, or extra bedroom without moving.

Loft Conversions and Garden Rooms: Quick Wins for Space

Loft conversions turn unused roof space into livable rooms. The key checks are headroom (minimum 2.2 m), roof structure, and access. Not every loft can be converted—low trusses or complex roof shapes may rule you out.

Garden rooms are essentially small buildings placed in the yard. They can serve as home offices, gyms, or extra living space. Planning permission is usually not needed if the structure is under 15 m² and doesn’t exceed 4 m in height. Choose a solid foundation and proper insulation to keep it functional year‑round.

Across all property types, the common threads are budgeting, regulations, and choosing the right materials. For a new build, factor in land costs, foundation work, and the latest building regulations. Extensions often need a solid foundation but can reuse existing walls, cutting material expenses. Loft conversions might require reinforcing joists, while garden rooms need a level base and good drainage.

Before you start, check these quick questions: Is the property type allowed under permitted development? Do you have the right permissions for plumbing or electrical work? What is the realistic budget after adding design, labour, and contingency?

By answering these, you’ll know whether a new build, extension, loft conversion, or garden room is the best fit for your goals. Each option can boost your home’s value, improve comfort, and give you the space you need—just pick the one that lines up with your timeline, budget, and planning constraints.