Transitions between old and new affect whether an extension feels coherent. Differences in height, material and structure should be visible early.
What the drawing needs to explain
Draw one section through the kitchen, glazing and terrace. Include finished floor levels, the roof edge and shading position; separate supplier sketches do not fully show these relationships.
Coordinate finished levels
Compare floor levels, ceilings, thresholds and the garden. Include layers still to be added, not just rough construction dimensions.
Design hidden junctions
Structure, weather protection, insulation and finishing meet at the connection. The trades should use the same detail.
How to review the result
At completion, walk from the cooking area to the terrace. Check the opening with the intended furniture in place and review the light with any shading closed.
Which trade-off matters?
A wide garden opening takes away wall space for cupboards. Compare a fully glazed rear wall with a smaller opening and a targeted rooflight, looking at both from the same seat.
A situation to test your plan against
Imagine extending the kitchen while keeping the dining table inside the original house. The addition should also bring useful light to that table. Include the existing room and the place where you read or work in the daytime.
Questions for your own property
- Are finished heights known?
- Who designs the junction?
- How are material differences handled?
How can the original room avoid becoming darker?
Assess the old and new rooms on one drawing. An additional rooflight becomes a reasoned choice when you know where light is needed and how sunlight and heat will be managed.
Illustrative design situations, not evidence of completed work. Assess decisions against the actual property.