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
Place existing and proposed elevations side by side and add a window-opening section. Mark visible changes and elements requiring adaptation inside.
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
Compare the completed window arrangement with the approved drawing. Then check operation and adjoining internal finishes, including areas not visible in the elevation.
Which trade-off matters?
New performance and existing proportions need assessment together. A different frame profile can affect glass area, reveals and internal finishes; compare the complete detail, not just the product rating.
A situation to test your plan against
A distinctive window arrangement or entrance can define a house while its interior needs improvement. Separate elements that establish the elevation from those limiting daily use. Comfort improvements then begin with a clear design boundary.
Questions for your own property
- Are finished heights known?
- Who designs the junction?
- How are material differences handled?
Can comfort improve without making the house unrecognisable?
Identify defining proportions and details first. Test technical options against them, including internal junctions and operation; an elevation impression alone is insufficient.
Illustrative design situations, not evidence of completed work. Assess decisions against the actual property.