FAQ’s

Manhole Risers FAQs

At WhirlyGig, we often receive some commonly asked questions about manholes. That’s why we’ve created a list of FAQ’s to effectively answer these questions.

How Much Do Your Manhole Risers Weigh?

The WhirlyGig thermoplastic form weighs approximately one pound per inch of height compared to concrete grade rings that weigh 35 pounds per inch of height (e.g. a 7” WhirlyGig thermoplastic form is ~7lbs whereas the same height concrete grade ring is ~245lbs).  Due to this the potential for injury is significantly reduced and installation can easily be performed by one person.

How Fast Is The WhirlyGig Installation Process?

With our revolutionary WhirlyGig Manhole Riser solution we’ve simplified the entire process so that it’s safer, more effective, and takes no more than six minutes to install (less for experienced crews).

Are WhirlyGig Manhole Risers Corrosion Resistant?

Another problem associated with traditional manhole riser solutions is that they degrade relatively quickly in the presence of corrosive gasses such as hydrogen sulfide which is found in sewer and stormwater systems.  Since the WhirlyGig Manhole Riser is manufactured from Linear Low Density Polyethylene it is impervious to just this type corrosive environment.  In fact, once they are installed, they will provide over 25 years of maintenance-free service.

Do WhirlyGig Manhole Risers Prevent Inflow & Infiltration?

By eliminating cracks and the use of grout with our thermoplastic forms, WhirlyGig is the most effective system in stopping inflow and infiltration in wastewater systems. This, in turn, keeps out contaminants like oil and runoff from making their way into sewer and stormwater systems.

What Goes Into the WhirlyGig Manhole Riser Installation Process?

With our revolutionary Manhole Riser solution, we’ve simplified the entire process so that it’s safer, more effective, and takes less than six minutes to install. View the WhirlyGig process video here or read more about it by visiting our Manhole Riser Installation page.

How Does WhirlyGig Cost Compare To Other Manhole Riser Solutions?

With our revolutionary Manhole Riser solution, we’ve not only provided a cost competitive riser itself but also simplified the entire process so that it’s safer, more effective, and takes less than six minutes to install. Visit our WhirlyGig Project Calculator web page and use the Gigulator (WhirlyGig calculator) to do your own comparison to see just how much the WhirlyGig Manhole Riser solution will save you!