How to Insulate Septic Tank Risers

Stephen Hasty

Septic tanks and pump tanks installed in septic systems possess maintenance access holes pre-cast or cut into septic tank lids. Septic tanks buried several feet underground require risers to allow maintenance providers access to the tank for cleaning, monitoring and on-going maintenance. Prone to freezing when installed in northern climates, septic tank installers commonly insulated tank tops. Maintenance access hole risers can also be insulated when installing new systems or can be retrofitted to existing tanks. Insulating access risers is a simple way to protect septic tanks from freezing.

Septic tanks lids and risers can be insulated to provide protection from freezing temperatures.
  1. Remove soil around the septic tank riser with the excavator. Hand shovel near the riser to reduce the potential for riser damage or dislodging the seal from the riser to the tank.

  2. Measure the circumference of the riser and cut the insulation to this measurement with a sharp knife. If rigid insulation is used, score the back of the insulation with the knife to allow the insulation to form around the round shape of the riser.

  3. Apply the adhesive to the insulation to the insulation and to the riser material. Be sure the adhesive is rated to bond both materials.

  4. Wrap the insulation around the riser.

  5. Tie rope around the insulation to hold in place until the backfill can be replaced and the adhesive cures.

  6. Replace the excavated soil around the riser with a hand shovel or excavator. Take care to not dislodge the seal from the riser to the tank.