House brief: rooms, areas and circulation

Before drawing a single line on a floor plan, you need to know exactly what your house should contain. That is your brief: a detailed list of every room, its area, its purpose and how it relates to adjacent spaces. Without a clear brief, your architect — or you yourself — is designing blindly. The result: undersized rooms, absurd circulation routes and a budget that spirals out of control. Here is how to build a solid house brief.

What is a house brief?

A house brief (also called a schedule of accommodation or functional brief) is the design specification for your home. It answers three questions:

1. Which rooms? — number, function, any special requirements.
2. What sizes? — minimum area for each space.
3. What relationships? — which rooms need to be close together, and which should be kept apart.

It is the document you hand to your architect or designer, or use yourself when laying out your floor plans. Without it, you are designing in the dark.

Reference areas by room

The figures below are recommended areas for each space. They represent comfortable minimums — go below them and the room starts to feel cramped.

Living spaces

Bedrooms

Bathrooms and WCs

Service spaces

The method for defining your brief

Step 1: List the rooms

Start from your daily life. For each activity, identify a space:

• Morning: waking (bedroom), washing (bathroom), breakfast (kitchen/living).
• Daytime: working from home (study), children playing (bedroom/living), unpacking shopping (pantry).
• Evening: cooking, eating (dining/kitchen), relaxing (living room), bedtime.
• Weekend: DIY (garage), garden (terrace access), having guests (guest bedroom).

Step 2: Assign areas

For each room on your list, assign an area using the tables above as a reference. Add everything up to get your target net internal area.

Step 3: Check budget compatibility

Your net internal area multiplied by the cost per m² must fit within your construction budget. If it overruns, go back to Step 1 and prioritise.

Circulation: the skeleton of the floor plan

Circulation covers everything that lets you move from one room to another: corridors, hallways, staircases. It typically accounts for 10 to 15% of the net internal area. Less = an optimised plan. More = wasted usable space.

Principles of good circulation

1. Separate day and night zones — Day spaces (living room, kitchen, study) and night spaces (bedrooms, bathrooms) should be independently accessible. In a two-storey house this happens naturally. In a single-storey home, distribution is critical.

2. Minimise corridors — A corridor does one thing: let people walk through it. Every metre of corridor is a square metre that serves no other purpose. Favour rooms that open directly onto one another, or use open-plan living spaces to create natural flow.

3. Direct kitchen → entrance access — Essential for unpacking the weekly shop. It sounds obvious, but a utility room between the garage and the kitchen is genuinely life-changing.

4. WC accessible without crossing a living space — For guests. A WC tucked at the back of a bedroom is a design error.

5. Central staircase — In a two-storey house, the staircase should sit at the heart of the plan, not in a corner. It should serve all rooms without creating long corridors.

The schedule of accommodation: a practical tool

Here is an example schedule of accommodation for a 120 m² net internal area, 4-bedroom, single-storey house:

Note: 120 m² net internal area + 18 m² garage + circulation = ~155 m² total floor area.

Common brief mistakes

1. Forgetting storage — Allow at least one built-in wardrobe per bedroom (60 cm deep), a pantry and a hallway with dedicated storage. Without it, the house will feel cluttered within weeks of moving in.

2. Undersizing the kitchen — Below 10 m², an open-plan kitchen feels cramped. Allow room for the work triangle (fridge – sink – hob) with a minimum 120 cm of clear passage.

3. Forgetting the utility room — A washing machine crammed into the bathroom is a flat-dwelling compromise, not a new-build solution. Plan a proper utility room of 4–6 m².

4. Neglecting the entrance hall — A 2 m² lobby is an airlock, not an entrance. Design a proper welcome space with storage, a bench and a mirror. 5 m² minimum.

5. Too many corridors — If your circulation exceeds 15% of net internal area, the plan is poorly optimised. Revisit the layout.

From brief to floor plan: the transition

Once your brief is finalised, you have everything you need to move to design:

1. Budget confirmed → construction budget signed off.
2. Brief complete → every room, its area and its adjacencies.
3. Plot analysed → footprint, orientation, access.
4. Style decided → single storey or two storey, contemporary or traditional.

With these four elements in place, your architect or designer can start working effectively. If any one of them is missing, the design will inevitably need to be reworked.

Key takeaways

The brief is the most underestimated step in any self-build project. Yet it is what determines whether your home will be a pleasure to live in or a daily source of frustration. Take the time to write it carefully, challenge it as a household, and test it against your budget. Everything else flows from it.