The children share a bedroom. The home office is the kitchen table. Winter is long, the family is large, and there simply is not enough room. You know the feeling — the house is fine, the neighbourhood is right, but you are just 20–30 square metres short.
This is one of the most common reasons people consider moving. But there are often better — and cheaper — alternatives.
Three ways to more space
1. Make better use of what you have
Many homes have hidden square metres. Before you build an extension, look at whether the existing floor plan can be optimised:
Open up. In many detached houses from the 1960s–80s, the ground floor is divided into small, separate rooms with narrow corridors. By removing a non-load-bearing wall between the living room and kitchen — or between corridor and living room — you can create a connected space that feels significantly larger. Cost: 10,000–40,000 DKK depending on the wall and finish.
Use the basement. If you have a basement with reasonable ceiling height (min. 2.1 m) and a dry climate, it can be used as a utility room, hobby room, teenage den or home office. Note: a basement does not normally count as living space in the building register (BBR), and there are requirements for moisture, daylight and ventilation.
Convert the loft. An unused loft space with sufficient ceiling height can be converted into a bedroom, office or children’s room. This requires dormers or skylights for daylight, insulation and a proper staircase. Cost: typically 200,000–500,000 DKK depending on scope.
Built-in solutions. Niches, cupboards under stairs, sleeping lofts and sliding walls can solve a surprising amount — especially in flats and smaller houses.
2. Build an extension
When the existing home cannot accommodate any more, an extension is the next step. The most common types:
Garden room or conservatory. The simplest form of extension. An insulated garden room of 15–25 m² typically costs 150,000–400,000 DKK. It provides extra living space and connects inside and outside — but beware: a cheap garden room can feel cold in winter and hot in summer.
Ground-floor extension. A proper extension in brick or timber that expands the ground floor. Typically 15,000–25,000 DKK/m². This requires a building permit and must comply with the plot coverage ratio and the local plan.
First-floor extension. If the plot is small but the roof allows it, you can build upward. This is technically more demanding — the foundation must be able to bear the load — but provides space without consuming the garden.
3. Move walls, not address
Sometimes the answer is not more square metres, but a better distribution of the ones you have. An architect can help you see possibilities you cannot see yourself:
- Can the bathroom be moved to make the bedroom larger?
- Can kitchen and living room be opened up so the space feels twice as large?
- Can the entrance be reconfigured so the hallway does not steal 8 m²?
- Is there an unused room that could be given a new function?
It is rarely about major rebuilding — often one intervention changes the entire experience of the home.
What are you permitted to build?
Before you plan, know the framework:
- The plot coverage ratio determines how many square metres you may build in total on the plot. Typically 30% for detached houses. With a 800 m² plot, you may build up to 240 m² in total — including the existing house.
- The local plan may set additional restrictions: maximum height, distance to boundary, materials, roof form and colours.
- The Building Regulations (BR18) set requirements for insulation, daylight, accessibility and energy.
Always check with the municipality before you begin. A pre-application dialogue typically costs nothing and can save you from expensive surprises.
What it costs
As a rule of thumb:
- Remove a non-load-bearing wall: 10,000–40,000 DKK
- Convert loft: 200,000–500,000 DKK
- Garden room (20 m²): 150,000–400,000 DKK
- Extension (30 m²): 450,000–750,000 DKK
- First-floor extension: from 600,000 DKK
Prices vary significantly depending on quality, materials and contractor rates in your area. Always get at least two quotes.
Which houses have the most potential?
- Detached houses from 1960–80 with unused loft — many have a pitched roof with good ceiling height, but the loft is only used for storage. These are often the cheapest extra square metres you can get
- Bungalows — built as single-storey, but often on large plots with low coverage. Room to extend — or to build up
- Terraced houses — limited plot, but often with unused loft space or basement. Think vertically here
- Brick villas — typically well-proportioned, but with many small rooms and narrow corridors. Open up rather than extend
Start by understanding your needs
What do you actually lack? Space for an extra child? Peace and quiet to work from home? Somewhere to be together without being on top of each other? The answer determines the solution — and it is not always the most expensive solution that is the right one.
If the problem is more fundamental — that the family has grown and the house cannot accommodate you — we have a separate guide to when it makes sense to extend or move. And if you are considering a proper extension, you will find prices and an overview in our guide to extension costs.
If you primarily lack daylight or better air quality, these can sometimes be resolved without extra square metres — with new windows, skylights or a revised floor plan.
Sources: BR18 (Danish Building Regulations), Bolius extension guide.