Making plans for a new building? If you want to build an addition or start a new construction project, you need to make sure that nothing important is under the ground. This can include gas pipes, water pipes, and sewers, all of which are important parts of our homes’ underground infrastructure.
If your project calls for it, you should know how to build a bridge over a sewer pipe. Read on to learn from the experts at CyberSewerhow to build a bridge over a sewer pipe, including how to make sure that neither your home’s drainage system nor the public sewer system is damaged.
What should I watch out for?
You need to find out what drainage pipes are on your property and where they go underground. Sewer pipes take wastewater from more than one house and are usually on your property. Lateral drains carry wastewater from a single house to the public sewer network outside that house’s boundary. You can read here to find out who is responsible for your drains.
If you don’t know where the drains under your house are, a CCTV drain survey is often the best way to find them. This can help you plan your project so that it doesn’t interfere with the existing infrastructure.
Can I build a bridge over a sewer?
Existing pipes might get in the way of where a foundation is supposed to go, and it wouldn’t be possible to build around them. One example of this is a sewer pipe that runs from the back of a property and crosses the line where the concrete foundation for the new addition is supposed to go. You should never build foundations along the length of a pipe, and if you want to build parallel to the direction of a pipe, the foundations must be on one side or the other.
If you are building foundations at an angle to a sewer pipe, you can put concrete on either side of the pipe and build a bridge over it. This is a common way to build a bridge over a sewer pipe.
Can You Build Over A Sewer Line?
Yes, it is possible to build on top of a private drain. This also applies to adding building extensions. But, as we’ve already said, if your building will be within one meter from a public lateral drain, you’ll need a Build Over Agreement.
How Close Can I Build To A Sewer Line?
The building foundation should end at least 150mm below the bottom of the public sewer pipe if it is less than 1000mm from the edge of the public sewer.
A 45-degree line can be drawn up to the bottom edge of the foundation where the edge is more than 1000 mm away. This can assist avoid foundations from being deeper than necessary.
It is crucial to remember that each water company may have special requirements for the design. As such, when submitting the build-over or build near public sewer application, the application officer should get in touch with you or your architect to discuss any necessary extra information.
What if I build on top of a drain?
If you build over a sewer or drain that is already there, you could damage the pipes. This could cause the pipes to leak or get clogged, which can cause health problems, bad smells, and damage to the environment. It also makes it harder, more expensive and takes more time to replace and fix broken drains and clear out clogs.
You also shouldn’t do any building work that makes it harder for the water authority to get to sewer pipes and keep them in good shape. There are rules & regulations about how close you can build to sewers and drains, and you should read these carefully before making any plans for the building.
Can I put foundations over drains?
It’s important to know that the building regulations say that buildings can’t be built within or more than 3m of a drain unless special measures are taken. This is true for soils like silt and sand. If the pipe is bigger than 30cm in diameter, you may need a 5m easement. Extensions and buildings must not be constructed over an inspection point on a sewer or manhole.
The good news is that you can sometimes reroute and move drains that are in the way of your building work. Drains are part of sewers, pipes, and manhole covers that work together to make a complicated network. This means that it is not always enough to just move one drain. Instead, you might have to think about rebuilding the drainage system somewhere else.
Before you start, you need to make sure it is at the right depth and get permission from your local water authority. Because of these things, it may not be possible in some situations. Working with expert drainage surveyors like those at CyberSewer can help you find the best solution for your needs.
Build Over Agreements
If you are building over a public sewer or within 3m of a sewer or drain pipe, you need a Build Over Agreement from the water authority. This may even be written in your house deeds, especially if you own a newer home. Before doing any work, you must make sure you have permission.
Is there ever a time when I can’t build on top of a sewer?
Yes. There are times when you won’t be able to build on top of a sewer:
To connect a new house to a sewer, the water authority may need to give permission and sometimes even do work.
There can’t be any driven piles within 15 meters of a public sewer. After this kind of sewer has been put in place, contractors, structural engineers, and architects can help with a lot of the work and coordination.
A Build Over Agreement is not likely to be given for new detached developments. Instead, the sewer needs to be moved somewhere else. But if you do this work yourself, you will have to pay for it.
If you want to build near this or other access points, you can’t build over a manhole. Instead, you have to move it. Because smells and flooding are more likely to happen inside a building with a manhole, the only solution is to move the manhole to a better place.
If you want to add on to your house to make it better, you might find a manhole where the foundation of your new building will go. If you see pipework, you must first get permission from your water authority.