I've to connect a 110mm soil pipe to an existing 4" clay sewer pipe. It will be near enough at a right angle.
Depth will be about 750mm-900mm.
To make it roddable I will need an inspection chamber. There is obviously a relationship between the diameter of inspection chamber and depth to permit the use of rods. I'm keen to install the smallest I can get away with as they are not cheap things. Advice please.
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