Septic Tank Installation
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It is very important that you have correct venting and connections relating to your particular tank location and site situation. Klargester provide guidance in their Technical Data Sheet, TDS0004. "Points to consider before siting your Septic Tank." a summary of which follows.
- Building Regulations require the system to be adequately ventilated. A Klargester septic tank needs fitting with an appropriate cover and frame and connection to a correctly designed and installed soil stack system which ensures adequate ventilation. An additional local air inlet can be fitted to the tank where circumstances and conditions require it. The direction of the prevailing wind in relation to the property(ies) should be considered when selecting the tank site. If an air admittance valve has been installed inside the property, perhaps within the roof cavity, then the septic tank must be independently vented.
- For dimensions of septic tanks and independent venting arrangements see Klargester drawing No. DS0521 (2.7m3 to 4.5m3) & DS0008 (6m3 to 9m3) or PD0213 (2.83 to 4.6m3).
- A fall of about 1 in 40 is recommended for the drain from the house to the tank. (Although newer plastic products may allow a fall of up to 1 in 80).
- A fall of about 1 in 200 is required for the land irrigation drain. These drains should end a minimum of 10m distance from any water course.
- A suitable cover and frame must be fitted relative to the neck size. Klargester covers and frames allow venting when connected to a soil stack system. Any other suitable covers and frames may be used.
- Covers & frames, any other access or inspection points, may need sealing with a mixture of grease and sand to prevent gases escaping at ground level.
Your plumber or installer should be consulted to check the drains to ensure that the installation and pipework conform to building regulations, and septic tank installation guidelines. The pipe layout must not allow the water to be drawn from water traps or U bends which normally prevent gases rising into the house.
It is good practice to install inspection chambers before and after the septic tank so as to enable inspection of the effluent quality being passed into the irrigation system.
Septic tank factsheets: