Design basis
The foundation should follow the structural and building-control information appropriate to the project.
Groundworks
Foundations
Foundation work begins with the load, ground and nearby constraints, not with a standard trench depth copied from another property.
Photos, drawings or a short description can help explain the current condition.
Groundworks · Foundations
Start below the finished surface
Trees, drains, made ground, neighbouring structures and water conditions can all alter the approach. Setting out and inspection are as important as the concrete itself.
Ground, access and water
Excavation stability
Depth, soil and weather affect safe working and the risk of trench collapse or water ingress.
Concrete placement
Formation cleanliness, level, access and pour planning should be ready before concrete is ordered.
What to mention
What Flyson needs to understand about the ground
- Describe what is already known about design basis.
- Explain the priority or constraint around excavation stability.
- Include enough context to discuss concrete placement without assuming a product or method before the property is understood.
Questions specific to foundations
Are all extension foundations the same?
No. Ground, trees, drainage and load vary by site, and requirements can change after excavation exposes actual conditions.
Who inspects foundations?
Where building control applies, the relevant inspector normally needs to see excavations at the required stage before concrete is placed.
Can old foundations be reused?
Only where their position, dimensions, condition and capacity are properly established for the new design.
Continue exploring groundworks
Site preparation
Good site preparation protects access, neighbours, existing property and the programme before the main construction work begins.
Explore site preparationExcavation
Excavation work needs a defined depth, safe method, material plan and understanding of what may lie below the surface.
Explore excavationDrainage groundworks
Drainage work is about levels, capacity, access for maintenance and a lawful destination for water or waste.
Explore drainage groundworksRelated work
View extensionsExtensions
Extension setting-out, foundations, drainage and finished floor levels begin in the ground.
Related work
View drivewaysDriveways
Formation, sub-base and drainage determine how a driveway performs below its surface.
Project enquiry
Ask about foundations.
Explain what the ground must support and any known access, level, drainage or excavation constraints.