Repairing Root Damaged Brick Manholes

How successful a repair to a root damaged chamber will be is dependant on a couple of factors such as the severity of the root ingress and the amount of room you have to work in.

The first job is to strip out the roots and access where the ingress is coming through, quite often simply removing the cover and frame and reseating them will do the job. Likewise the sand and cement benching or channel pipes can be replaced if this is where the roots are getting in.

If the top few courses of brick work have lifted they can be stripped down and rebuilt or even replaced using a concrete manhole section, if there is ingress
throughout the chamber the joints can be raked out and re-pointed or the inside walls can be rendered.

Quite often though we simply have to strip down the manhole and replace it with a modern concrete or plastic chamber, making sure that it is protected against future root ingress.

Repairing Concrete Manholes

If the chambers is made up of 600 x 450 concrete sections they can be dismantled and put back together, use a slurry mix of mortar between the rings and during the back filling process throw a protective band of concrete on the outer side of the joints.

On larger diameter concrete sectional chambers there are a couple of joint repair methods that can be used as well as methods for coating the internal wall of the chamber, more on this below.....

Plastic Inspection Chambers

Similar to the concrete sections but use a sealant between the rings and surround the outside of the chamber in concrete or at the very least cover each joint.

Lining Root Damaged Manholes

There are several epoxy and fiber-reinforced cementitious lining methods available for lining the internal walls of manholes, for the most part the cost of these repair methods would be prohibitive for a single domestic installation but if multiple chambers need attention they are worth considering. Another benefit of this kind of repair is that the coating is usually spayed on so even the tightest of chambers can be fully coated.

We have in the past repaired single domestic chambers using epoxy patch lining materials, again the cost can be prohibitive but if it saves disturbing a tar-mac driveway or excavating and newly installed patio it is worth getting a couple of quotes.