Project Guide

How to Install a Whole House Water Filter

Choose Filter Location
Main water supply shut-off valves on copper pipe in a basement.

The first step of water filter installation is to choose a location that is easily accessible. You’ll need to access the unit to regularly change the whole-house water filter cartridges, so be sure no obstacles interfere with installation. Select a position near the main water shut-off valve, and keep in mind that a filter mounting bracket will be secured to the home structure, such as a wall or floor joist.

Cut the Pipe
A person using a deburring tool to remove burrs from a cut pipe.
  • Turn off the water supply.
  • Refer to the template included with your filtration system and then mark the pipe at the exact location. 
  • Follow the manufacturer’s instructions to ensure you cut away enough pipe to accommodate the filter and any connecting fittings.
  • Use a tube cutter to make two cuts at the marks. Remove the section of pipe where the filter will be placed. Have a bucket placed underneath the location to catch any water remaining in the water line.
  • Remove burrs on the cut pipe with a reamer or deburring tool.
Assemble Parts and Install the Filter
A person installing a whole-house water filter.
  • Install a shut-off valve at the exposed ends of the supply line. These remain open during normal use but can be closed when replacing a whole-house water filer.
  • Dry fit all fittings beforehand to ensure good connections, following instructions for your model.
  • Fittings for a typical installation will include a compression nut, ferrule and fittings to connect the water line to the incoming and outgoing sides of the filter assembly.
  • Use PTFE tape for the fittings and do not overtighten.
  • You might need an adaptor on either side of the filter in order to join your size and type of pipe.
Add a Grounding Jumper Cable if Needed
A whole-house water filer installed with a grounding jumper cable.

Some older homes use metal water pipes as the ground for the electrical system. Determine if your electrical panel has its ground wire attached to your water supply pipe.

If the ground wire is attached to the pipe, the water filter housing might have broken this ground path. Install appropriate grounding clamps to the metal pipe on either side of the filter. Secure a length of heavy-gauge copper wire across the filter from clamp to clamp and secure tightly.

This step is necessary only if you have copper or galvanized water pipes.

DIYers with a moderate amount of plumbing experience can install carbon whole-house water filters. After learning how to install a water filter, consider using The Home Depot’s water filter installation service if you don’t want to tackle the project on your own.

Need help identifying a tool or material for installing a whole house water filter? Find products fast with image search in The Home Depot app. Snap a picture of an item you like and we'll show you similar products.