Moving a kitchen sink? Everything you should consider7 min read

Moving a kitchen sink can significantly enhance the kitchen’s layout, and at first glance, it may appear to be a simple plumbing job. However, many homeowners don’t realize the potential structural, plumbing, and electrical work that may be necessary to move the kitchen sink. 

Moving a kitchen sink’s position can be simple or complex, depending on how far the sink is being moved. Water supply, drainage, and venting are the three main considerations. A slight shift requires basic re-plumbing, while a major relocation might involve new vent stacks, altered drainage, and disruptions to cabinets and flooring.

On my first house renovation, I decided to move the entire kitchen to the back, plumbing and all. Here are some before and after pictures: 

Old Living Room
As you can see, there was no sink or plumbing here before! This was previously the living room.
Finished kitchen sink
My new kitchen sink is on the right of this picture.

But, here’s the twist: the hot water pipe made it a bit trickier than your average DIY project. In navigating the complexities of rerouting hot water from the front’s combi-boiler to the back, I discovered that moving a kitchen sink is more than just a simple swap.

My solution involved routing hot water from the front’s combi-boiler, up through the upstairs bathroom, and then back down to the new kitchen sink. Whilst this is unconventional it works surprisingly well (or so my tenant tells me!).  

This experience taught me that moving a kitchen sink isn’t always a straightforward task. While your situation might not mirror mine, this article aims to help you navigate the process of ‘moving a kitchen sink’ by exploring all potential considerations, the same considerations I took into account. 

Determining the Complexity & Steps for Moving

Moving a kitchen sink depends primarily on water supply lines, waste pipes, and venting. Whilst this seems simple, the difficulty of moving a kitchen sink also depends on the following factors:

  • How far the sink is being moved. This is the most important factor and usually determines the overall difficulty and the project cost. If the sink is only moving a few inches, it’s likely an easy job with few complications (most base units have a 70mm service void behind them for plumbing work).
  • The state of your current plumbing. In other words, is the sink being moved to an area that already has access to drainage and a vent? Or will these factors need to be considered? Water inlet pipes are easier to install than both a vent and drainage.
  • Your kitchen layout. Moving a sink can entail modifying cabinets, counters, and plumbing lines. Relocating it can affect other cabinets and kitchen appliances like the dishwasher.
  • The structural setup of your kitchen. Relocating a sink can involve addressing surrounding cabinets and half walls. If the floor’s already ripped up, laying new pipes is easier, but breaking through a concrete kitchen slab can be costly and challenging (many homes are built on a concrete foundation). 

Whilst the difficulty of the project varies, the good news is that moving a kitchen sink is almost always possible. When I moved my kitchen sink, all of these factors were a serious consideration but my project cost less than $1000 (all in, including re-routing all the plumbing work in addition to the new sink).

Distance & Layout

The distance you intend to move your sink greatly influences the project’s complexity and cost. When I moved my sink from the front to the back of the house, I had to remodel the kitchen’s entire layout. It wasn’t just about moving a sink; it was about reimagining and reconstructing the entire space, a process that involved uprooting the flooring and innovating a new method to channel hot water to the sink.

If you are considering a whole new kitchen, consider the pros & cons of Home Depot vs Lowes – both providers offer reasonably priced and customizable kitchens.

Pipework behind cabinets
Notice how cabinets need to be modified to suit plumbing. What you’re looking at is my water supply line, waste, and an electrical wire covered in flexible plastic tubing.

Tip: if you live somewhere cold and are considering moving the kitchen sink to an external wall, consider the fact pipes may freeze. Keep plumbing out of exterior walls. 

Taken up floor in kitchen
Notice how we’ve had to remove all of the flooring and carpet to access the concrete foundation, which is where the pipework needed to be laid. The plumbing work is also visible and we had to build the cabinets around this.

Such an extensive move requires a holistic view of the kitchen. You’re not merely relocating a sink but potentially installing new countertops, and cabinets, and even repositioning the dishwasher. There might also be the need to rewire for garbage disposal.

In considering all of these factors, it might make sense to gut an entire kitchen and create a new one if you’re spending a lot of money. If you are considering moving your kitchen upstairs, there are a few solid reasons why kitchens are normally downstairs. 

Not all projects involving the move of a kitchen sink involve this much disruption. If your sink is only moving a few inches or so, it should be an easy job. You can usually extend your existing drain line, use the same vent, and simply use longer faucet supplies.  

Plumbing Challenges

Plumbing was the most time-consuming aspect of my project. Rerouting the hot water pipe from the combi-boiler at the front to the back required tearing up the flooring, making a new drainage system, and ensuring a hot water supply to an area that wasn’t previously serviced.

My solution was to channel the hot water through the upstairs bathroom before directing it to the kitchen sink below. Although unconventional, it worked.

Generally, the three primary plumbing considerations for moving a kitchen sink are:

  1. How will the new kitchen sink receive both cold and hot water?
  2. Where will the new kitchen sink drain grey water?
  3. How will the new kitchen sink be vented?

Moving the water supply is usually straightforward. You can extend your faucet supply line, and if you need longer lengths, connectors or fittings coupled with extended tubing can achieve the desired reach. 

However, this is not the case when relocating a kitchen sink between rooms, as I did. Such a move might require tearing up the floor or sourcing a water supply from an upstairs room.

Drainage can be challenging when relocating a kitchen sink. Drainage pipes aren’t easy to shift. Often, drainage routes through the basement, making the establishment of a new line tricky. Second, even if you retain the same drainpipe, the trap arm’s length (the tube connecting the sink to the drainpipe) can pose problems. 

This arm is a horizontal pipe attached to the P-Trap that channels wastewater to the drainpipe. Its length and slope are crucial for effective drainage. Although specific maximum lengths may vary by state, a common guideline is a ¼ inch per foot (or a 2% slope), meaning the trap arm should descend by a quarter-inch for every horizontal foot.

Lastly, venting a sink is necessary, and finding a new vent path can be tough, especially with an upper floor, as multiple vent pipes can become an eyesore. The challenge increases with multiple floors above the kitchen, often demanding innovative plumbing solutions. New vents might be concealed in closets, cupboards, or pantries. Also, if the sink’s relocation isn’t along the same wall, it could necessitate a new vent stack, adding to the permits, time, and project costs.

Tip: consider an air admittance valve (sometimes a ‘cheater vent’) which allows air to enter the plumbing drainage system to balance the pressure when water drains out of the system. These are particularly useful for moving a sink to a kitchen island. Get professional help and check local building codes. 

Structural Considerations

When relocating your sink, envisage the existing structures and what construction work might need to happen to relocate your water supply, drainage, and vent. 

I had to rip up the entire floor of two rooms in order to move my sink, but every home has its unique structural challenges. I have listed the main structural things to bear in mind: 

Foundation: For homes with a slab foundation, moving a sink might require drilling into or trenching the slab to reroute the plumbing. This is very disruptive and costly.

Flooring: If you’re rerouting plumbing through the floor, you’ll need to cut or drill into it. After the work, repairs or replacements will be necessary, and it might be challenging to match existing flooring. If the sink is being moved to a previously unplumbed area, like an island, trenching the concrete slab (if on a slab foundation) might be needed.

Walls: Moving water and vent pipes sometimes requires opening walls. Afterward, wall repairs, including patching, painting, or re-tiling, will be necessary. If moving the sink involves relocating or removing windows or making other structural changes to walls, there could be implications for the structural integrity and weatherproofing of the house.

Electrical considerations: If outlets or switches are in the way of the new sink location, they’ll need to be moved. Additionally, if you’re adding a garbage disposal or dishwasher in the new location, you’ll need electrical connections for them.

Tip: I encountered an awkward half-wall around the sink. Consider innovative ways to incorporate such structural elements into the revamped kitchen design.

DIY vs. Professional Help

While I love DIY, it’s essential to understand when you’re out of your depth. Whether or not you use a professional for help will depend on a) how far you’re moving the sink and b) your capabilities around the home. 

If you’re only moving the sink a few inches you can probably move it yourself (if you’re an experienced DIYer). It probably won’t require structural changes, might need a bit of re-plumbing for the wastage pipes, and may require a faucet supply line extension. 

If on the other hand, your sink is being moved a greater distance, this is likely a job left to professionals. It might require plumbers, electricians, carpenters, and general building work depending on the scope of the project. 

Cost Considerations

The cost of moving a kitchen sink varies but is based on how far you are moving the sink and the scope of the project. 

My project cost just under $1000 and this involved moving the sink from the front to the back of the house, but I was fortunate with minimal wastage, venting, and supply work needing doing (and this was in 2019).  

Homewyse estimates the cost to move plumbing 10m at $1042. 

Forbes estimates the cost of roughing in a kitchen sink at $300 – $500. 

Alternatives to Moving a Kitchen Sink

As you may have noticed, moving a kitchen sink can be a large job. If you have gotten this far and think that moving your kitchen sink isn’t an option, there are alternatives to doing so.

Adjust Your Sink Only

Many people consider moving their sink just because the current sink either doesn’t work well or is off-center.

Both of these problems can be adjusted without actually having to move your sink. Small adjustments like this do require removing and reinstalling your sink but are less costly to do because your sink will be in the same area and use the same pipes as before.

A Second Sink

One of the most popular options is adding a second kitchen sink. If your current sink is just not in the greatest location, or maybe doesn’t serve your needs, don’t be afraid to add a second one.

Move Other Appliances

Do you want your kitchen to be closer to the dishwasher? Or maybe your sink is too close to your stove for comfort. Surprisingly, moving your other appliances is easier than moving your sink and is something that should be considered.

For example, if you have a flat-top induction stove, this can easily be installed on another countertop rather than the one next to your sink. And because the stovetop just requires an outlet, it’s much more simple than moving your sink. 

Conclusion

The implications of moving a kitchen sink vary greatly depending on how far the sink is being moved and the setup of the existing plumbing. As someone who’s been through the trenches of sink relocation, I’d stress the importance of preparation and informed decision-making. 

While moving a kitchen sink can offer significant advantages for aesthetic and practical reasons, it can be a complex project.

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Hi, I'm Ed, and I run BuildFanatic! I enjoy providing the best possible information on a range of home improvement topics.

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