Planning Building Setting Out Before Excavation
Planning building setting out before excavation means agreeing how the building’s position, orientation and levels will be transferred from drawings onto the site. It also means naming who will mark the layout, who will check it and who can authorise digging.
Pegs and string lines alone do not confirm that a building is correctly positioned. For a project in Uganda, use the actual property information, coordinated drawings and advice from your appointed professionals.
Quick planning summary
Agree these responsibilities before the excavation team and equipment arrive. Roles may overlap, but each task needs a named person responsible for completing or accepting it.
| Decision | Responsibility to agree | Evidence to request |
|---|---|---|
| Building position and orientation | Appointed designer and setting-out professional | Current site layout with clear dimensions |
| Boundary information | Appropriate survey professional | Relevant survey records and clarification of uncertainty |
| Drawing coordination | Relevant designers | Consistent layout and foundation information |
| Position and level references | Person responsible for setting out | Recorded reference locations and descriptions |
| Position checks | Named competent checker | Dated measurements and check record |
| Permission to excavate | Person authorised under the project arrangements | Written release identifying the work permitted |
| Marker protection | Site supervisor and excavation team | Protection arrangements and reporting procedure |
1. Define what needs to be set out
Identify what must be located on the ground. Depending on the design, this may include building corners, structural grid lines, wall lines, foundation positions and offsets from agreed references. Ask the appointed professional which marks will control the excavation.
A building outline is not necessarily an excavation outline. Foundation details and the working method may affect the excavation limits. The excavation team needs clear instructions rather than having to guess what a string line represents.
Make the meaning of each mark clear
Agree an identification system for pegs, profiles and drawings. Record whether each mark represents a centre line, wall face, offset or other reference, so someone joining the project later can understand it.
If you are considering future extensions, tell the designer before finalising the present building position. Use the checklist for planning future extensions in Uganda to prepare for that discussion, while keeping decisions specific to your property.
2. Review site constraints and boundary information
Arrange a site review before treating the layout as ready to mark. Discuss access, slopes, drainage features, existing structures and visible services that could affect the building position or excavation. Ask what further investigation is needed where information is incomplete.
Do not assume that a fence, hedge or occupied edge establishes the legal property boundary. If boundary information is uncertain or disputed, seek clarification from an appropriate survey professional before using it to position the building. Setting out should not be used to resolve a boundary disagreement informally.
Ask the appointed professional which planning or building approval conditions affect the layout. Do not copy boundary clearances or building lines from another property; check the requirements for your project.
Keep position checks separate from excavation safety
A checked building position does not establish that excavation is safe. Underground services, neighbouring structures and other site hazards need appropriate assessments and working arrangements. Existing records may need verification rather than being treated as complete.
3. Coordinate drawings and agree reference points
Give the setting-out team the current drawings intended for the work. Confirm that the site layout, architectural plans and structural foundation information agree on the dimensions and positions needed for excavation.
Refer conflicting or missing dimensions to the responsible designer. Do not choose whichever measurement is easiest to use or casually measure a printed plan to fill a gap.
Record drawing numbers, revisions and issue dates. A file described as “latest” can become ambiguous after another revision is issued. Keep superseded copies separate from the information being used on site.
Record position references and the level datum
Ask how the building position will relate to reliable site references. Agree the level datum—the reference from which project levels will be measured—and record its location and meaning. Later teams should not introduce a different reference without review.
Discuss whether offset markers or profiles are needed outside the excavation area and how they will be protected. The responsible professional should choose an arrangement that suits the site, rather than copying a generic diagram.
4. Budget for setting out and verification
Ask quotations to state what setting-out work is included. Check whether the allowance covers the initial visit, recording references, checking the marked position and any further attendance needed before excavation.
Do not assume that a general groundworks price includes every survey or checking task. Allow for foreseeable coordination needs, such as checking revised drawings or returning after planned site preparation. The appropriate allowance depends on the scope, site conditions and responsibilities.
Agree how repeat visits will be handled
Set out how additional attendance will be authorised and priced if markers are disturbed, the design changes or access prevents the planned work. Review the reason, scope and cost before instructing extra work.
Keep the verification allowance clear enough to see what it covers. Removing a check to save an immediate cost can leave a position error unresolved until excavation or construction has progressed.
5. Name who sets out, checks and authorises excavation
Confirm that the person carrying out the setting out has competence suited to the work. Name the checker and the person authorised to release excavation before the excavation team is waiting on site.
The checking arrangement should reflect the project’s complexity and risk. Ask your appointed professional whether a separate check is needed and what it should cover. An owner’s visual inspection can raise useful questions, but it does not replace technical verification.
Agree what acceptance means
Agree project-specific accuracy requirements and acceptance criteria with the relevant professionals. There is no universal tolerance to apply without considering the design and method. The checker needs to know which drawings, references and criteria to use.
Record who will:
- Resolve conflicting dimensions.
- Record measurements and any departures from the drawings.
- Instruct corrections or stop the affected work.
- Communicate permission to the excavation team.
Put these responsibilities in project instructions or meeting notes so that a change of personnel does not leave a gap.
6. Set a clear check before digging starts
Plan the sequence so references can be established, positions marked and checks completed before excavation disturbs the area. Coordinate site clearance and access so preparatory work does not remove essential markers or evidence.
Use a pre-excavation hold point
A hold point is an agreed stage beyond which work cannot proceed until the required review is complete. Here, it creates a clear pause between marking the site and authorising excavation.
The review should cover relevant dimensions, orientation, reference levels and the layout’s relationship to verified site information. The responsible professional should select the appropriate measurement and geometric checks. A footprint can look square while still being in the wrong place.
Before permission is given, brief the excavation team on:
- What each marked line represents.
- Which references must remain protected.
- The limits and conditions of the work authorised.
- Who to contact if marks are lost or discrepancies appear.
Pressure to keep equipment working should not override an unresolved check.
7. Control changes and protect markers
Once the position has been checked, treat any proposed movement of the building as a design change. Even a small adjustment may affect boundaries, drainage, access or other planned work. Refer it to the relevant professionals before altering marks.
Record the instruction, revised drawing and marks that are no longer valid. Where only part of the layout changes, identify the affected area clearly to prevent old and new information being combined.
What to do if a marker moves or disappears
Stop relying on that marker for the affected work. Ask the responsible person to re-establish and verify it from reliable information. Replacing a peg approximately where someone remembers it standing is not a sound basis for continuing.
Review marker protection as machinery routes, storage areas and working spaces change. A reference that was safe during setting out may later be in a busy access route.
8. Keep the check records and excavation authorisation
Before excavation is authorised, confirm that the check record states what was checked, when and against which drawing revisions. Give each unresolved discrepancy a named person responsible for resolving it. Do not sign a broad acceptance statement if the supporting information is incomplete.
Photographs can help record marker locations and site conditions, but they do not replace measurements or professional verification. Label useful images so their purpose remains clear after the site changes.
Records to retain
- Coordinated drawings used for setting out.
- Descriptions and locations of retained reference points.
- Setting-out measurements and checking records.
- Written clarifications and authorised changes.
- Permission to excavate, including any limits or conditions.
Keep these records accessible to those supervising later work. Permission to begin excavation does not confirm every subsequent foundation position or level. Agree further inspection stages as the work progresses; the checklist for inspecting finished work in Uganda can also help you plan later quality checks and handover records.