Kitchen feed pipes in an 8 inch [200mm to conform to EU] x 2inches [50mm] deep channel in the concrete floor screed the existing timber supports have gone rotten.
What's the best way to cover?
1. Re-insulate pipes with new tubular insulation [currently partly wrapped in fibreglass insulation tape] lay fillet each side of the pipes tap a 6inch [150mm] x 3/4 inch [ 20mm neae enough] board, Lift the board straighten the edges of the fillets and fill cavity between fillets to cover pipe level to fillets with silver sand, Re-lay dry board to ensure level. Lift board/s and allow fillets to set.
2. Same insulation? lay thin sand over pipes and follow with mix of 3-1 sharp sand to floor level. No access would be needed to these pipes [I hope] once floor covering is laid.
The leveling board will not be used for the cover. Dry board will be used as board on wet cement can bow.
[b]comment on standard of work in 1976[/b]
If I'd caught the builder his voice would be 2-3 octaves higher. And I think the surveyour was asleep as I've just uncovered a manhole and one backfill drain [one more to uncover].