A detailed, step-by-step guide for installing grid-tied solar on your home:

DIY Solar Guide for Canada

Want to learn how to install solar panels on your own roof? This is the guide you’ve been looking for!

Table of Contents

Introduction to DIY Solar

Welcome to the Solar Circle Co-op DIY Solar Guide! This guide will walk you through all the steps required to install rooftop grid-tied solar on your home in Canada. The purpose of this cooperative is to provide access to low-cost solar kits and to share the knowledge required for Canadians to install DIY solar. Many Canadians have already installed DIY solar (check the “completed-project” tag in the forum). If your roof is not super steep, it’s a very reasonable home improvement project that will save you lots of money.

Don’t be afraid, it’s not as hard as it sounds. If you read through this guide, you’ll have a solid understanding on what’s involved.

Do it yourself (DIY) solar involves:

  1. Designing your solar rooftop install (calculating how much electricity you usually use, then picking the right size solar kit)
  2. Planning and applying for any necessary permits you’ll need (you’ll likely need to work with a master electrician to get your electrical permit)
  3. Buying a solar kit (panels, inverters, racking) and checking for any damages upon delivery
  4. Installing the racking, inverters and solar panels yourself (or hiring a roofer to do this work)
  5. Doing your own electrical work then having a master electrician approve it (or hiring an electrician to do everything)

DIY solar can offer significant savings compared to using “turn-key” solar installers. To compare, you’ll need to get quotes from some turn-key solar installers in your area to calculate your own numbers, but a very rough estimate is:

  • Cost per watt for a DIY install: $1.33 (ex: $13,300 for a 10kW AC solar install)
  • Cost per watt for a turn-key install: $2.50 (ex: $25,000 for a 10kW AC solar install)

The above $1.33 DIY estimate assumes you will do all work yourself and a master electrician will review your electrical work. If you end up hiring an electrician and/or roofer to do the install work, your costs will go up.

First step: check your shingles

Before you even start considering solar on your roof, you should calculate how much life your roof shingles have. Asphalt shingles usually last around 20-30 years. You may not want to install solar panels on a roof if the shingles will need to be replaced within the next 10 years anyway.

Second step: check the capacity of your main electrical panel

In order to calculate how much solar you can add to your main electrical panel, you need to figure out two things:

  1. Main Breaker Rating: This is typically the big breaker at the top of your panel (e.g., “100A” or “200A”).
  2. Busbar Rating: This tells you how much current the panel itself can safely carry. It’s usually labeled somewhere inside the panel (sometimes printed on the door or panel interior).

Find your busbar and main breaker ratings, then follow the below “backfeed” steps to calculate how much solar your panel will allow:

Rule 64-112 of the Canadian Electrical Code says the formula to calculate the backfeed breaker size is:
(Busbar rating × 1.25) – (Main breaker rating) = (Maximum allowed backfeed breaker size)

For example:
(125A x 1.25) – 100A = 56.25A
So in this example you could install a 50A breaker to backfeed in your solar install. Breakers can only be loaded to 80% of their rating, so the actual amount of amps this breaker can be loaded to is:
(Maximum allowed backfeed breaker size) x 80% = (Maximum allowed backfeed amps)
50A * 0.8 = 40A

Our solar kits use APSystems DS3-L microinverters, which output a maximum of 3.2A at 240V each (which is 768VA (aka watts)). So to calculate how large of a solar install 40A would allow using these microinverters, the formula is:

((Maximum allowed backfeed amps) / 3.2A) x 768 watts = (Maximum AC System Size)
(40A / 3.2A) x 768 watts = 9600 watts (or 9.6kW)

For this example, we could install a 9.6kW AC solar system on the house.

If the above calculations for your main panel result in a system size that is significantly too small to cover your annual electricity usage (see next step below for this), then you would need to include the extra cost of upgrading your main electrical panel as part of system install costs (the price to do this can be in the $3,000 – $5,000 range).

Calculate your annual electricity consumption

  1. Calculate how much electricity your home used for the last 12 months. Pull your electricity usage statement from last month, and then pull the statement from 12 months before that. Grab the total kWh meter count from the 12 months old statement and subtract the value from last month. This will tell you how many kWh your home used in the last year.
  2. Your solar system will produce plenty of electricity in summer and not much in winter. All provinces in Canada have various net metering programs where you earn extra credits during times of excess electricity production, and in the winter, you can use these credits to pay for your electricity consumption when you’ll be mostly pulling from the grid. In basically all scenarios across Canada, you’ll want to install a solar system that produces enough annual electricity that will cover your expected annual usage. There are nuances between the provinces (Alberta has ‘Solar Club’ rates available), so you’ll need to research the options from your local utility to fully understand how their net metering system will work for you.

Calculating AC System Size

Now that you know your annual kWh consumption, you can calculate how large your solar install should be (AC System Size).

Start by identifying the photovoltaic potential (kWh/kWp) value for your area in Canada from this great Natural Resources map which shows irradiance across Canada: Solar Resource Map of Canada

Examples:

  • Alberta 1200 kWh/kWp
  • Ontario 1100 kWh/kWp
  • NS/BC 1000 kWh/kWp

Using your photovoltaic potential value, the formula for calculating your AC System Size is:
AC System Size (kW) = annual electricity consumption (kWh) / photovoltaic potential (kWh/kWp)

So for a home that has an annual electricity consumption of 10,500 kWh in Alberta, the ideal AC System Size would be:
10,500 kWh / 1,200 kWh/kWp = 8.75 kW AC System

This is a rough estimate and we can dial this more later, but for now, let’s use this to calculate system costs.

Solar Kit and Electrical Costs

Check the list of our solar kits here. Click on the one that most closely matches your above estimated AC System size. For the above example, the 22 Panel 8.4 kW Solar Kit best fits. Generally speaking, you’ll want to pick a kit that is equal to or lower than you electricity consumption (some utilities won’t allow you to go larger). If your local utility allows it and you have your reasons, feel free to pick a larger system.

A solar kit will include:

  • solar panels
  • microinverters
  • a ‘Wireless Energy Communication Unit’ that monitors/controls the inverters
  • rails and roof mounts which connect to your rooftop
  • all hardware to connect the panels and inverters to the rails, the rails to the roof mounts, and the roof mounts to the roof
  • AC trunk cables to connect all the inverters together
  • a rooftop junction box which the trunk cables will flow into

The solar kit does not include:

  • The electrical cabling & materials to connect the rooftop junction box to your main electrical panel. If you keep the cable inside your house (from attic down to your main panel) you’ll probably use AC90 armoured electrical cable. You’ll likely need a subpanel installed beside your main panel to act as a disconnect. Some people contract an electrician to do all of this, while others do the work themselves and just have the electrician review their work. Either way, at a minimum your local jurisdiction most likely requires you to have an electrical permit pulled by a master electrician. You’ll need to research the local rules in your area for solar roof installs to verify this.
  • Zip-ties which are quite useful for cable management

If you do all the electrical work yourself, a very rough estimate for electrical costs would be:

  • $400 to hire a master electrician to pull permit and review your work
  • $1100 for electrical cabling & materials

Is this project worth doing?

Before you go any further and start digging into any design specifics, you should check whether the financials of your project make sense. Can your electrical panel handle the size of your new solar install? If not, include the costs of an electrical panel upgrade ($3-5,000). Sum up all the costs of: the solar kit, the electrical, plus roughly $200 in shipping freight costs. This is a ballpark estimate of your solar install.

Now is a good time to create a spreadsheet and do some calculations on how much you currently pay for your electricity. How long would it take before this solar install would “paid itself off”? It might be worth looking into the Canada Greener Homes Loan (up to $40,000 for 10 years at 0% interest), which allows for DIY solar installs. Your local area might have other incentives or rebates for solar installs (which may or may not allow DIY solar), and if you’re in Alberta you can use Carbon Offset Credits (check solaroffset.ca or rewattpower.com). If you think the financials make sense and want to proceed, let’s jump into design specifics.

Note on the Ontario ‘Home Renovation Savings Program’: This program does not allow net metering, so it doesn’t really make sense for most homeowners considering solar in Ontario. Additionally, this program does not allow DIY installs.

Design Specifics – OpenSolar.com

You can now start designing how your solar panels will fit on your roof and also get a more accurate estimate on solar production based on the angle and slope of your roof.

A great free tool to do this is: OpenSolar.com. Click ‘Log In’, then click ‘Create free account’. Once logged in, enter your address, click New Project, now click on the ‘Design’ tab at the top. An odd-looking 3D model of your home will be displayed. Click ‘Add Panels’, and select the panel type that is listed in your solar kit (for example Longi LR5-54HPB-410M).

Now place one panel on your roof, and once it is placed, you can click the white ghost grid markers that appear around the first panel to click and fill out the panels on your roof. Now click the “Back” arrow at the top where it says “Back to XX Panels System”. You can now view various details of the system. This tool allows you to visualize the layout of the panels on your roof and will provide more accurate annual production numbers based on the angle and direction of your roof.

To get an even better visual of your roof and to understand potential obstacles like venting which may change your solar panel layout, it’s worth checking if your local municipality has an online GIS system available online. Often, this local GIS will provide high-resolution satellite views of your roof which you can study to plan and optimize your solar panel layout.

OpenSolar Design notes:

  • Our solar kits assume you’ll use portrait layout for your design (portrait uses less racking).
  • Multiple Arrays: Having one array is the simplest design. Simple is ideal. If you want to have multiple arrays, you’ll need to modify the solar kit that you order to have additional end caps for the end of your rails and potentially additional junction boxes. You’ll need to design how you’ll connect the arrays together. Your Array #2 needs to connect to the junction box located at your Array #1 (or vice versa) where you can then connect with the main AC90 cable that will go down to your basement to a subpanel near your main service panel (assuming your design uses an internal AC90 cable, you can alternatively run a cable or conduit on the exterior of your house – more on that later).
  • Multiple Arrays – Connect the arrays: One method to connect the arrays is by going through your attic (benefit here is that you have a nice clean appearance by avoiding exposed cabling/conduit on your roof). For this, you would use an extra rooftop junction box at Array #2, feed the AC trunk cable through your attic over to the junction box at Array #1. Another (arguably easier) strategy would be to use a cable (or conduit) rated for rooftop exposure that connects over to your Array #1 junction box. For this, you would use a rail-mounted junction box at Array #2, where you would connect your Array #2 AC trunk cable to a properly rated cable over to your Array #1 junction box. You absolutely need to have a solution that is rated for rooftop exposure. Using your master electrician to approve your design will be required.

Design Specifics – Kinetic Solar Configurator Tool

Now that you’ve got your roof design completed in OpenSolar.com, you can verify the components required in your solar kit.

All of our solar kits are designed using simple two or three-row portrait layouts. It is very likely that your design is differrent and so it is highly recommended to use the Kinetic Solar Configurator Tool to verify the count of components in your solar kit order (especially which size rails to order).

It’s a simple and useful tool, here are the steps:

  • Go to https://configurator.kineticsolar.com/pitched-roof
  • Enter location info. They will ask if terrain is rough (wind is blocked by hills/trees/houses) or wide open (higher winds). Pick normal importance.
  • Little side note on truss spacing: Your racking will most likely be require a roof mount every 48″. So if your truss spacing is 24″, then you’ll connect to every second truss. If your spacing is 16″, then you’ll connect to every third truss. The Kinetic Solar instruction manual (you can download from the solar kit detail page) goes into more detail on this.
  • Enter the solar module listed in our solar kit. Example: LONGi LR5-54HPB-410M. The sizing will determine your racking configuration.
  • Use Conventional rail style
  • Setup your layout, rows and columns. You can de-select individual panels by clicking on them.
  • Roof mount is Flashing Kit with Single 4″ Self Drilling Screw
  • 3″ L-Bracket size is default
  • No to cable raceway (we’ll provide cable zip-ties in the kit)
  • Yes to microinverters
  • Rodent protection (highly recommended if you have pigeons or squirrels around your house)
  • 6 inch Mesh Kit if you want Rodent Guard

You did it! The tool now provides a breakdown of components required to meet your design. Grab these numbers and use them to modify the count of components in your solar kit. The summary page is all you need, but if you want a few more details you can create an account to login and download their “Bill of Materials (BOM)”. Here is an example of what their BOM file looks like.

Paperwork: Interconnection agreements and permits

Ok, you’ve got your design sketched out. You’ve confirmed the components in your solar kit. Now let’s do some final research on permits:

  • Lookup your local jurisdiction rules on solar installs. Do you need a local building permit? Are there rules about how close the panels can be to the edge of your roof? They may want you to do some weight load calculations for your roof. Start making a spreadsheet to keep track of the various requirements you’ll be dealing with. Understand the requirements for the electrical permit.

Now if you’re ready to hit the GO button on the project, the first step is to get permission from your local utility. They are the gatekeepers of the electrical grid which you be connecting to. They will likely want to know how large your solar system will be, what your expected production amount will be, what your past annual electricity consumption was and what your electrical design will look like. They want to make sure the local infrastructure can accommodate your connection.

Once your utility approves your solar install, you can proceed with applying for any other permits. At a minimum, you’ll likely need an electrical permit which will require a master electrician.

Co-op members are encouraged to share details and tips about how they handled their own utility application in the forum under the “utility-permits” tag. Some utilities are picky and annoying to work with, so tips for utility permit applications can really save time. Documenting and sharing tips makes it easier for everyone following your footsteps.

Order your DIY Solar Kit

Once your utility has given you the green light to proceed, it should now be safe to order your solar kit.

As noted above, the solar kits are designed with the assumption of a simple single array. It is highly recommended to follow the Kinetic Solar Configurator Tool section above to confirm the components in your solar kit order.

When you submit the order, we will respond with a shipping quote (this varies greatly and can be roughly 2-3% of your order total). Once materials arrive, check for damage before you accept delivery. In the event of damage upon delivery, notify the delivery driver before accepting the delivery. Also take pictures and notify us immediately. If you need to return any goods, there is a 30% restocking fee.

Find an electrician and/or roofer

You now have to decide if you’re going to install the roof racking and solar panels yourself, or if you’re going to hire roofers to do this work for you. You’ll also want to search for an electrician that is willing to work with you. Do you want them to simply review your design, pull the permit and review your completed work? Or do you want them to do all the work?

If you find a good roofer or electrician and are willing to recommend them, please share these details in the forum using the “recommend-electrician” or “recommend-roofer” tag. Sharing your experience and lessons learned is a great kindness to other co-op members who may live in your local area.

Order useful tools, safety gear and other materials

If you’ve decided to do the roof install yourself, here is a recommended list of safety gear and tools:

  • fall protection harness
  • a good ladder with stabilizer arms
  • solar panel suction cups
  • a sheet of solar stickers you’ll need for electrical labeling (your disconnects, breakers, and bi-directional meter)
  • impact driver & drill
  • work-belt
  • hack-saw (for cutting rails)
  • chalk (for making marks on shingles)
  • extra-long measuring tape (measuring full length of your array on roof is very useful)
  • knee pads
  • caulking gun
  • wide & flat pry bar (for loosening shingles when installing roof flashings)
  • waterproof nylon “cable glands” that match the size of your AC trunk cable (you will use this to waterproof where the cable enters your rooftop junction box; required size is likely PG13.5 (which accepts a range of 7-12mm).

If you’re going to do electrical work yourself, you’ll need to confirm your electrical design with your electrician before creating a list of required materials.

Electrical

Your local jurisdiction almost certainly requires a master electrician to handle the permit for your electrical install. The amount of work you want your electrician to do is a sliding scale. On one end of the scale, you can either hire an electrician to handle everything (design the electrical work, pull the permit, and do all the physical work). On the other end of the scale, you can try and do as much of the work yourself and simply have the electrician approve your work (have them review/approve your design BEFORE you start any work, and then also have them review/approve your work once you’re done). If you’re competent the electrician may simply accept photo documentation of your work.

The third option is somewhere in between these two extremes. Maybe you want the electrician to do everything, except maybe you want to do the physical and time-consuming work of pulling cable from your attic to your basement (assuming finding a path to run the cable inside your house is even possible – otherwise, running cable on the exterior of your home will be required).

Electrical – Grounding/bonding for your solar panels

Your electrician will need to make a design decision regarding the grounding and bonding of your solar panel install. Some jurisdictions/electricians want to have a bare copper ground that runs from your solar panels down to your main panel and which is separate from the ground in your AC90 cable. Other electricians are okay with bonding the solar panels to the ground in the AC90 (this bonding would occur in the rooftop junction box). You will need to follow the guidance of the master electrician that pulls the permit for you.

Electrical – Single Line Diagram

Each solar kit comes with a single line diagram (SLD) template you can use to start a conversation with your electrician. You can download this from the product page for the solar kit you are purchasing.

To better understand the SLD, check the APSystems DS3 microinverter datasheet to check how many microinverters can be placed per 20A or 30A branch circuit. For example, a 10AWG 30A branch can have 7 microinverters. If you have a design with more than 7 microinverters, then you’ll have two branch circuits. In a two-branch design, each branch circuit has two wires (plus ground) which will connect to the two wires in the AC90 cable in the rooftop junction box. If you have only one branch circuit, you only need an AC90 cable that has two wires; otherwise, you’ll need a 4-wire AC90 cable. To understand the terminology when talking about these cables, an “AC90 10-4” cable has 4 conductors that are 10AWG plus a bare bonding conductor. Work with your electrician to verify all these design specifics.

Electrical – Order materials

Once your electrician approves your design, you can then source your materials from an electrical supply store (their prices are usually much better than Home Depot). Your list may look something like:

  • good quality wire strippers with wire cutter
  • main lug subpanel with one or two breakers (one breaker for each branch circuit; check the Single Line Diagram)
  • AC90 (2 or 4 conductors) that runs from your rooftop junction box to your new subpanel in your basement
  • breaker for your main electrical panel (you’ll need to calculate the correct gauge and length. Likely 10AWG.)
  • AC90 (3 conductors) that runs from your subpanel to the new breaker in your main electrical panel (again, you’ll need to calculate the correct gauge and length. Possibly 6AWG.)
  • cable clamps for your subpanel and main panel for where the cables enter/exit

Note: Depending upon your jurisdiction, it’s possible that you might not even require a subpanel and could feed directly into your main panel. Work with your electrician on this.

Electrical – Running cable from roof to basement

You’ll need to inspect your house to see if it’s possible to run an AC90 cable from your attic down inside your house to your basement. If this is not possible, you can run conduit (or something like Teck cable) on the exterior of your home, then penetrate into your basement near your main electrical panel.

Running cable inside your home will avoid having a cable or conduit running down the side of the exterior of your home, will minimize outside penetrations into your home, and allows you to use lower cost AC90 cable instead of Teck cable or conduit. Work with your electrician on your design.

If you can find a way to run cable inside your home, depending upon what your electrician decides on grounding/bonding, you’ll possibly be running both a bare copper ground wire and AC90 cable from your junction box down to a newly installed sub-panel (next to your main panel). Pulling this cable is both labor intensive and time consuming. Doing work in attics is not fun. Even if you decide to have your electrician do all of the electrical work, you might want to do the cable pulling yourself to save money.

If you need to run wire on the exterior of your home, either using Teck cable or inside a conduit, an electrician can do this work for you. Teck cable requires special tools and connectors. Your electrician may prefer using conduit. If you’re familiar with conduit, maybe you want to do this work yourself.

Final steps & installation

  • Climb up into your attic to understand your roof truss spacing.
  • Print out your OpenSolar design. Calculate the total length and width of your array (remember that each mid-clamp adds some spacing between each panel). Mark where you want the microinverters to go, which branch circuits each microinverter will plug into (if you have more than one), and where the junction box will go.
  • Read all the documentation available. Read the install PDF provided from Kinetic Solar. Read the install PDF from APSystems. Watch some YouTube videos from Kinetic Solar to understand how to install the roof mounts with their flashings (gentle taps with a hammer to find the joint location, then pre-drill the hole. If you miss, no biggie, drill again to find center. The wide flashing will easily cover your mistakes).
  • Get on the roof wearing your fall protection gear. Always minimize your risks. Always wear the fall protection. Do not work when it’s windy. Now you can measure, verify spacing, measure. Chalk the outline of your solar array to understand your panel placement, measure where rails will go. Understand the spacing of the roof mounts. The max distance between roof mounts is 48″ (every 2nd truss, if you have 24″ truss spacing. Or every 3rd truss if you have 16″ spacing). Now, start installing the roof mounts for the bottom rail. Even if your roof is not steep, it’s a good move to install this rail as something to stand on to support you while you install the other footers higher up on your roof. The roof will feel much more comfortable and safe once you have the bottom rail installed.
  • Once rails are installed, hook up the microinverters. Placement is important to ensure the MC4 connector wires from the panels can reach the inverters (it is possible to extend the MC4 connectors, but it’s really best to avoid this if possible). As you install the solar panels, you can easily adjust the placement of the inverters if needed.
  • Select placement of the roof-top junction box. Watch video to understand ideal placement. Drill hole in roof, install junction box.
  • Have electrician review all electrical work before installing solar panels. Take quality pictures of all your electrical work and share them with your electrician. This may be sufficient for their approval.
  • Electrical labeling: Use electrical stickers (like these) to label your disconnects, breakers, and bi-directional meter. This is required, and your utility will not allow you to turn on your system without this labeling. There is no industry standard for what stickers you should use, but your outside meter should say something like “WARNING – DUAL POWER SOURCE SECOND SYSTEM IS PV SYSTEM”, your main disconnect subpanel should be labeled as “MAIN PHOTOVOLTAIC SYSTEM AC DISCONNECT” and the breakers should say “SOLAR ELECTRIC CIRCUIT BREAKER IS BACKFED”, etc. The sticker saying “SOLAR PV SYSTEM IS EQUIPPED WITH RAPID SHUTDOWN” is good too. Ask your electrician if they have a preference on labeling.
  • Start installing the solar panels. Design a method of transporting the panels up to your roof safely. Minimize your risks. Using a suction cup holder (like this one), it is possible for one person to carry a panel on their back using one hand while climbing up a ladder, then you can slide the panel up onto the roof while standing at the top of the ladder (each panel is roughly 45 LBS). Having a helper, if possible, would be wise and make things easier.
  • Hiring a roofer to be your assistant during your install day might be a good idea. Offering to help other co-op members in the forum during their install day would be an incredible gift. If someone helps you on your install day, it would certainly be kind to pay it forward and offer your help to others. Use the tag “install-day-help” on the forum when posting.

Requesting permission to turn on your system

Once your install is complete, you’ll need to provide your completed electrical permit to your utility and request permission to activate your system. Your utility will possibly need to install a bi-directional meter before this happens.

Once they give you permission, CONGRATULATIONS, YOU CAN NOW TURN ON YOUR SOLAR SYSTEM!

Hit the breaker switch and celebrate! It’s incredibly rewarding to monitor the performance of your solar system, and the feeling of satisfaction doesn’t seem to fade over time. You’re now the proud owner of a power plant operating on your roof. Pat yourself on the back, you did it!

Once you have completed your project, please share details of your project in the forum with the tag “completed-project” so other co-op members will learn from your experience and also be inspired.