Building or renovating and wondering what size electrical panel do I need for my house? We can help with that decision. Read on.
In a new house or renovation a minimum size for a panel is 24 circuit 100 amp mandatory code. Larger sizes are available for standard residential panels. The electrical code has a section to help based on square footage and electrical demand loads.
What Size Electrical Panel Do I Need For My House?
Bye Canadian electrical code you are required to have a minimum of a 100 amp 24 circuit panel in any residential dwelling.
This applies for off grid homes or homes that are not powered by the grid. It also applies for all home on grid. However in most cases this is not practical in a newer style home as this panel is just simply too small.
Most newer homes go with a 200 amp service for resale value.
Standard panels are 40 circuit and upwards of 80 circuit.
The price difference between 100amp and a 200 amp electrical service is not much, so much people will opt in to go with a 200 amp service on their home.
What Size Electrical Panel Do I Need For My House Based On Square Feet?
So in order to calculate the size service entrance in your home we always refer to section of eight of our codebook.
It’s stipulates load calculations on square footage, appliances, heating etc.
So bottom line is you need to get the square footage of your house in separate measurements .
Length times width, once you get those measurements you will need to convert each measurement into meters.
So for example if you have a 10 foot measurement convert it to 3 m. Once you have the meters conversion you can multiply to two.
As an for example 3 m x 3 m would be 9 m².
Are code stipulates so you must allow 5000 W for the first 90 m².
Anything over 90 m² you have to go for each portion.
If you have a 270 m² home it should be 7000 watts. 5000 watts for the first 90 m² and 1000 for each portion thereof.
The basement area can be reduced to 75% of that it’s a basement.
You will also need to include each floor of your property.
What Size Electrical Panel Do I Need For My House Based On Appliances?
By code you must allow 6000 W for electric range of an electric range is installed.
You also must allow 25% of each load exceeding 1500 watts.
So if you have a 1500 watt microwave that would be 250 watts. If you have a 3000 W hot water tank that would be 750 watts.
Heating roads do not get included in this portion as they are taking it 100%.
The appliance of device must exceed 1500 watts to be included.
What About Heating Loads ?
When you figure out a demand load calculation heating load must be taken at 100%.
.So as an example if you have a 10,000 watt heater you must take that for 10 kw.
There are different rules with individually thermostat control electric heat but we’re not gonna get into that at this point.
Commercial demand loads must be calculated at 80 %. This means you can not exceed anymore than 80% of the main service entrance capacity. A 200 amp service would be 160 amps max.
Do I Need To Count AC Loads?
AC loads or air-conditioning loads need to be counted at 100% as well.
So if you have an AC load of 10,000 watts you will need to include 10,000 watts in your calculation.
Keep in mind our code states that he does not need to include both AC and heating loads in your calculations.
It is very unlikely that you’ll be running both at once kind of defeats the purpose of either source.
How Do I Know How Many Circuits I Need?
Most smaller panels are 24 circuits however this is just simply not enough.
Most newer 200 amp panels can take up to 40 full size breakers or 80 mini size breakers.
Recently within the last couple years they have also come out with a panel that you can put 60 full size breakers or 120 mini size breakers.
Preferably we like to go with the larger panel as codes always changing and you’re always having things added to your panel.
Don’t go short on this as a cost for a larger panel is not that much more.
You can see more on some of the panels that we recommend and I recommended product stage at the link at the bottom of this article.
Do I Need To Count The Garage In The Sizing?
Including a garage need to be needs to be treated the same as the basement area.
Whatever the square meters in the garage would be treated at 75% of its rating.
You can add this into the square meters of your total calculation.
Keep in mind you will also need to add in any appliances or equipment that exceed 1500 W like welders etc. Remember these are taking a 25%.
Do Electric How Water Tanks Count In The Sizing?
If you are using hot water tank for domestic hot water usage then you can use the 25% rule.
As an example as mentioned above a 3000 watt hot water tank you would use 750 W for this calculation.
However keep in mind if you are using hot water tanks in or using it for any sort of heating source than you need to take the rating at 100% so then in hot water tank would be 3000 watts
Below is an example of a mess load calculation for a calculation for a heating source in a home this is the overall demand low calculation and how you would size your service please follow this example if you’re trying to figure out the size of your service entrance.
270 m2 house
5000 watts for first 90 m2
1000 watts for second 90 m2
1000 watts for third 90 m2
6000 watts electric range
750 watts 40 gallon hot water tank @ 25%
15000 watts electric heat
10000 watts ac loads
250 watts built in microwave
1250 watts dryer
28250 watts total / 240 volt single phase= 117.70 amps
This would mean that you would require a 125 amp service minimum. We would go up to a 200 amp service as it is most likely cheaper due to it being mass produced. A 125 amp is less common thus costs more.
You can see more on the products that we recommend here…..