Checklist before the zero stage: what to verify before foundations
The zero stage sets the technical base for the whole house. Mistakes made here can be buried quickly: wrong level, missing service sleeve, weak waterproofing, unaccepted excavation or unclear contractor scope. A professional checklist before the zero stage should connect drawings, survey work, ground conditions, foundations, waterproofing and photo evidence.
Documents and setting out
Before excavation starts, confirm the current drawing set, foundation levels and building axes. The surveyor should set out the building, and the construction manager should confirm that the planned work matches the design and permit conditions.
Check soil information, groundwater level, designer notes and utility requirements. If the foundation solution changes from the design, record the decision in writing and attach it to the relevant drawing.
Site and excavation preparation
Access, spoil storage, material storage, drainage and excavation safety should be planned before machinery arrives. Poor site organization often leads to delays, extra transport or damaged materials.
After excavation, check dimensions, depth, levels, soil at the bottom and any water in the trench or pit. Concrete should not be placed if the excavation bottom is wet, frozen, unstable or not accepted by the construction manager.
Foundations, reinforcement and concrete
Before pouring concrete, confirm formwork, reinforcement, cover, connections, grounding and all service sleeves through the foundation. This is the cheapest moment to correct missing routes for drainage, power, water, heat pump, ventilation or external services.
Concrete should have a confirmed class, delivery method, placement conditions and curing plan. Keep delivery notes and photograph reinforcement before the pour, because those details become difficult to prove later.
Waterproofing and backfill
The zero stage is not only concrete. Check horizontal and vertical waterproofing, continuity of membranes, foundation insulation, drainage, protection layers and backfill method. Connections between foundation waterproofing and the future ground floor are especially important.
Backfill should be placed in layers and compacted according to the design or engineer's instruction. Poor fill under the slab can later cause cracking, settlement or moisture issues.
Acceptance before the next stage
Before wall construction starts, keep photos, confirmed levels, sleeves, waterproofing, backfill records and an acceptance note. The next crew should know exactly what level and condition they are taking over.
In BuildIQ, close the zero stage only when documents, photos and decisions are attached to the same stage. Once covered, this work is hard to reconstruct, so documentation matters.
before the zero stage
- confirm current drawings, levels and building axes
- check soil report, groundwater and designer recommendations
- plan access, storage, drainage, waste and excavation protection
- accept excavation before concrete: dimensions, depth, bottom and levels
- check formwork, reinforcement, cover, grounding and concrete class
- plan sleeves for drainage, water, power, ventilation and external services
- photograph reinforcement and sleeves before the concrete pour
- check horizontal waterproofing, vertical waterproofing, insulation and drainage
- control backfill material and layer compaction
- close zero stage acceptance before wall construction starts