Building over top of drainage pipes

If you are building an extension you will need to apply for Building Regulations, the local inspector can advise on arrangements where drains pass through or near the development.

on any project any services (pipes of any kind) should not be built on building inspecter will advise correct procedure where you would use concrete lintols to carry new walls over any pipes etc leaving room around pipes so they wont be damaged by any weight from any new building works

Building over drainage. Involve BC if needed. You have to excavate under the pipe to allow the concrete foundation to flow underneath and step back up either side if required. Then build over pipe with adequate concrete lintels bedded on block or the concrete step with a good bearing backfill with pea gravel. Everything depends on the type of drainage it could be local authority main sewer or just normal household drainage.