1.1.4-1
Basement excavation
Component Information
- Code:
- 1.1.4-1
- Sequence:
- 1
- Unit:
- m3
- Sub-Element:
- 1.1.4 - 4 Basement excavation
Basement excavation
details,including average depth of excavation, to be stated
Component Statistics
Measurement Rules
Included Items
Excluded Items
Measurement Rules (8)
The volume measured for basement excavation and disposal of excavated material is the area of the basement measured to the external face of the external perimeter walls multiplied by the average depth of excavation.
The depth of basement excavation should be measured from either the average existing ground level to the formation level or the adjusted ground level (i.e. where a new ground level has been established following preparatory groundworks) to the formation level, whichever is applicable.
The volume of contaminated material measured for disposal is the surface area of the contaminated material multiplied by the average depth of the contaminated material.
Quantity given for disposal is the bulk before excavating, and no allowance is made for subsequent variations to bulk or for extra space to accommodate earthwork support.
The area of earthwork support and working space measured is the full depth to all faces of excavation.
Other cost-significant components are to be described and identified separately. Such components are to be measured by area (m2 ) or linear measurement (m), or enumerated (nr) separately.
Work within existing buildings is to be described and identified separately.
Where the contractor is only responsible for designing specific elements and/or components of the building project (i.e. not the entire building project), contractor-designed work is to be described and identified separately.
Included Items (9)
Bulk excavation to form basements, etc.
Temporary or permanent support to the bulk excavation (e.g. earthwork support, caissons, steel sheet piling, etc.), including insertion and extraction of temporary steel sheet piling and caissons.
Additional excavation required to facilitate construction of basement retaining walls (e.g. where open excavation method is employed), including excavating, backfilling (e.g. with selected excavated material or granular material) and disposal of surplus excavated material.
Excavating below groundwater level.
Disposal of excavated material, including tipping charges and landfill tax (including inert, non-hazardous and hazardous material where not to be carried out as facilitating works).
Note: where no information relating to the ground conditions is available, an allowance is to be made within the construction risk allowance for the extra cost of removing unforeseen obstructions and dealing with unknown ground conditions. where no contamination/remediation strategy report exists, an allowance is to be made within the construction risk allowance for the extra cost of disposing of contaminated material.Disposal of surface water and groundwater, where dewatering techniques not employed.
Consolidating and compacting slab/bed construction.
Sundry items.
Where works are to be carried out by a subcontractor, the subcontractor’s preliminaries, design fees, risk allowance, overheads and profit, with allowance for these to be made within unit rate applied to element or component.
Excluded Items (9)
Excavation and earthworks for forming new site contours and adjusting existing site levels (included in sub-element 8.1.2).
Excavation and disposal in connection with trench and pit excavations associated with pile caps, ground beams, retaining walls, ground slabs/beds, raft foundations and drainage below the level from which the basement base slab is to be constructed (included in sub-elements 1.1.1, 1.1.2 or 1.1.3, as appropriate).
Construction of basement retaining walls (included in sub-element 1.1.5).
Excavation and disposal in connection with the construction of diaphragm walling (included in sub-element 1.1.5).
Construction of base slab/bed (included in sub-element 1.1.3)
Excavation and disposal in connection with formation of swimming pools, etc. below lowest floor level (included in sub-element 1.3.2).
Consolidating and compacting formation level to receive floor construction (included in sub-element 1.1.3).
Dewatering (included in sub-element 0.4.1).
Soil stabilisation (included in sub-element 0.4.2).
Navigation
Export
API Access
Access this component data programmatically:
GET /api/components/1.1.4/1/- Complete component details