How to keep your electric freestanding oven but replace the gas cooktop

How to keep your electric freestanding oven but replace the gas cooktop



You've got a fantastic free-standing electric oven...but you want to get rid of the integrated gas cooktop.

Not interested in throwing out a perfectly good electric oven and replacing the whole thing? Get ready for some good news! We've helped previous clients successfully solve this puzzle.
We don't recommend DIY with any of this. This article is to help communicate the result you're after to qualified tradespeople and show you how we can customise the process to your needs. You should always use a licensed electrician for any wiring and a licensed plumber to cap the gas supply line. While you're at it, get a cabinet-maker to build and install the benchtop too!
In this article we'll walk through the steps of how we achieved an all-electric kitchen for a client that did not want to replace their electric oven, so you can see what is involved and if it's an approach you'd like to try.
In this project, we installed an induction cooktop. We did this because the client wanted a unit that had comparable performance to their existing gas cooktop and was safe for small children. To find out more about the options for electric cooktops, have a look at this article.

Steps to replacing a gas cooktop

Step 1: Check the electrics 

If you're going to put in a hardwired induction cooktop, you need to make sure of two things:
1) You've got enough current coming from your mains supply to run the cooktop;
2) There is space on your switchboard for a dedicated circuit for the cooktop.
 
The first thing we did was to check the switchboard, which indicated a 63A mains supply to the property and a spare pole to put in a circuit.
Wondering why you need that amount of current? This article explains things further.

 
Just to be clear, the switch may say 80A but the mains supply is 63A (which is a standard amount of current for single-phase supply). The maximum current that switches can handle does not match the available current. I know, it confused us at first as well.

 Step 2: Switch off the gas supply to the cooktop 

There's already gas constantly leaking out of your cooktop1 2 3 but there's no reason to let that happen while the tradies get to work! It shouldn't be hazardous to pull your oven out from it's bay and follow the gas line to a shut-off valve.



 In this case, the client's valve was under their floor. One quarter twist later and the gas was shut off, leaving a safe space for the tradies to get to work.


 Step 3: Put the oven on shorter legs 

Most free-standing ovens have screw-fitted legs. The size of the screw threads is consistent, so it is surprisingly easy to find smaller replacement legs. In the case of this specific oven the existing legs were adjustable, but they didn't drop the oven down low enough to provide clearance for the new benchtop. They also didn't provide enough ventilation space to meet the manufacturers requirements for the induction cooktop.



Thanks to the universal screw fitting, we sourced a set of shorter fixed legs that dropped the oven down by the required amount to make space for the benchtop and cooktop installation.


 
Once the oven was at the correct height we stripped off all the gas cooktop hardware that wasn't bolted down, allowing the client to say goodbye to scrubbing scummy metal trivets forever!


Step 4: Install a benchtop over the new gap 

Our cabinet maker turned up with a lovely piece of salvaged messmate timber that was stained and pre-cut to the size of the cooktop. They installed a couple of supports into the back wall and existing cabinetry. The benchtop was screwed into the supports and siliconed into place to avoid liquids getting into the cracks between the existing and new benchtops.


 
Meanwhile, the electrician ran a supply wire from a new circuit breaker on the switchboard to a location for the cooktop isolator switch. The job of running a new wire from the switchboard to the kitchen was relatively straightforward for the electrician due to good underfloor access.
 
The client had decided ahead of time that one of the existing power points could be converted to the isolator switch to avoid cutting new holes in the tiles. The electrician also cut an access hole in the side of the existing cabinetry to run a supply wire for power to the hardwired cooktop unit.
Running new wires is an area where the cost and complexity of a job can escalate quickly through no fault of the tradie. To assist electricians in issuing an accurate quote, make sure you provide any information they need to understand the difficulty of running new wires around the home from the switchboard.

Step 5: Install the cooktop 

Once the silicone on the new benchtop was dry, the electrician dropped the induction cooktop into the cut-out, hardwired the unit and tidied up the wiring. After a quick systems test, we had an all-electric kitchen and a happy client!


Tips for repurposing your free-standing oven 

Based on these kinds of projects, we'd recommend the following to keep things safe, running smoothly and on budget:
  1. Have a plumber switch off the gas supply to the cooktop before starting any work.
  2. Make sure your mains supply is at least 63A. If it is less, expect to pay for a mains upgrade.
  3. Make sure your switchboard has at least one spare pole so a new circuit can be installed for the cooktop. If not, expect to pay for a switchboard upgrade.
  4. Get professional tradies to undertake any plumbing and electrical work. They will issue compliance certificates for any work that they do.
  5. Select your preferred induction cooktop and share the wiring requirements in the product manual with your electrician.
  6. Think about access to run a new wire from the switchboard to the cooktop site. Think about a possible location for an isolator safety switch. Discuss options with your electrician so you're both clear on the cost of installing the new wiring.
  7. Make sure the plumber and electrician provide certificates of compliance for the work they have done.
  8. You'll get a better result if you use a professional cabinet-maker.
  9. Work with your cabinet-maker to figure out the size of the cut out required in the bench top. They will also be able to advise the length of the replacement legs for the oven so there is enough space for the benchtop. Our client provided the cabinet maker with the induction cooktop ahead of time to ensure a snug fit.
  10. Make sure the cabinet-maker designs a gap for airflow between the top of the oven and the bottom of the bench. Ventilation is very important for induction cooktops. Refer the cabinet-maker to the cooktop product manual for installation requirements.
  11. If you can't coordinate the trades to arrive on the same day, we recommend getting the new benchtop installed before bringing in the electrician.
  12. Make sure that any gaps between benchtops are sealed with silicone to prevent liquids getting trapped.

Next steps 

Ready to take this one on? Excellent! You'll probably benefit from our article about How to find a trusted tradie.
 
Feeling a bit overwhelmed with it all? Join an Energy Freedom Homes Masterclass and learn to identify your needs, gain expert installation advice, and meet trustworthy tradespeople. Check your Masterclass readiness now!

References

1 Michanowicz, D. R., Dayalu, A., Nordgaard, C. L., Buonocore, J. J., Fairchild, M. W., Ackley, R., Schiff, J. E., Liu, A., Phillips, N. G., Schulman, A., Magavi, Z., & Spengler, J. D. (2022). Home is where the pipeline ends: Characterization of volatile organic compounds present in natural gas at the point of the residential end user. Environmental Science & Technology, 56(14), 10258-10268. https://doi.org/10.1021/acs.est.1c08298.
2 Lebel, E. D., Finnegan, C. J., Ouyang, Z., & Jackson, R. B. (2022). Methane and NOx emissions from natural gas stoves, cooktops, and ovens in residential homes. Environmental Science & Technology, 56(4), 2529-2539. https://doi.org/10.1021/acs.est.1c04707.
3 Thompson, D. (2022). Gas used in homes has links to cancer; leaks often undetected. U.S. News. Retrieved  2022, from https://www.usnews.com/news/health-news/articles/2022-07-01/gas-used-in-homes-has-links-to-cancer-leaks-often-undetected