What To Look For When Fitting Roof Solar Panels?
If you’re planning on harnessing the power of renewable energy, then fitting roof solar panels has to be at the front of your mind.
Why? Because they are a fantastic source of sustainable energy that can be used wherever you live. Plus, there are some great financial incentives to help with installation and provide you with the means to earn from the electricity you produce.
As you are here, I’m guessing that you’re already considering solar energy, but have some questions about the installation of roof solar panels on your property.
So with this in mind, we put together this guide to make it easier for you to get a big picture of what you need to look at when installing solar panels on your roof.
How Do I Know If Your Roof's Ready For Fitting Roof Solar Panels? Here Are 7 Critical Factors To Check
Not all roofs are born equal:
1. Is it made of suitable material?
2. What’s the roof’s condition?
3. Is the roof old?
4. Which way does it face?
5. Is it shaded?
6. What is the roof angle?
7. How big is your roof?
Let’s look at these factors in more detail.
What’s Your Roof Made Of: Is it A Suitable Material?
When looking at fitting roof solar panels the material the roof is made from is incredibly important. It needs to be strong and durable. Some of the best materials include:
- Metal: From corrugated iron to steel and aluminium they’re incredibly sturdy, particularly seamed metal roofs.
- Asphalt Shingles: Mainly used in newer houses they are ideal.
- Tiles: From concrete and ceramic to slate and clay they are standard on most roofs owing to their strength and life span.
- Composite: From fibreglass, PVC and thermoplastic polyolefins (TPO) they are tough.
Some of the not so durable materials that are ok but may need strengthening include:
Roof materials that aren’t good for solar panels and should be avoided include:
How Old Is The Roof: Will It Need Replacing?
If your roof is old and will need to be repaired or replaced in the next 20 years, then you’ll need to do any necessary repairs before fitting roof solar panels. Most solar panel arrays have a lifespan of between 15-25 years.
If you put solar panels on a roof that will need repairing or replacing before, then it’s going to be an expensive job to remove and then put them back. In fact, in most cases, it would be easier and more cost efficient to start again.
If you’re not sure about the integrity of your roof, it’s advisable to ask a roofer for their advice.
Is The Roof In A Good Enough Condition: Will It Need Repairing?
Similar to checking the age of the roof, it’s important to inspect its condition before you look at fitting roof solar panels. Make sure it’s going to be strong enough to bear the load and also if there any hidden repair issues lurking around.
Some things to look out for are missing tiles, water damage, rotting beams and holes. Even if there isn’t anything obvious showing, it’s worth having a chat with a roofer to get their opinion.
Which Way Does Your Roof Face: Where is Best When Fitting Roof Solar Panels?
Although they will work in most daylight conditions, fitting roof solar panels and positioning them to maximize the sun’s journey through the sky will help to optimize the generation of electricity.
Ideally, in the northern hemisphere, south facing solar roof panels are recommended but often this isn’t possible because of the way the property is constructed. Another factor to look at is whether the south facing roof is being obstructed.
If you can’t go south, then the next best positions are west and East facing. They produce 15% less energy than south. This is followed by north facing that generates 30% less electricity.
Is Your Roof Shaded: Will Your Solar Panels Be Able To Produce Electricity?
It’s a common misconception that solar panels can’t generate electricity in the shade. Although not quite an urban myth, you can, but not at maximum strength.
The issue is with the amount of shade and how many of the cells in the solar panel are being covered.
If you are concerned about roof shade, you can put light meters on your roof and monitor the shade throughout the day and season before deciding on the fitting roof solar panels and where to place them.
What Roof Angle Is Best For Fitting Roof Solar Panels?
There are two things to take into consideration: the angle of the roof and also the angle of the panel.
Angle Of The Panel
This is an important factor to be aware as one angle doesn’t fit all seasons. This is because the height of the sun changes throughout the year.
Overall, a 60% angle is good in the fall and winter, but in the spring that can be reduced to 45% and in the summer, 20%.
Something to remember, when buying solar panels make sure they are adjustable.
The Angle And Pitch Of The Roof
An overall roof angle of 15-40 degrees is about right for your solar panels. If you have a flat roof or a very steep pitch, then the contractor can adjust the panels accordingly.
Will You Be Able To Produce Enough Electricity: How Big Is Your Roof?
So you have a structurally sound roof, at the right angle, with plenty of sun, but will you able to generate enough electricity for your needs?
Roof size is the last bit of the jigsaw in fitting roof solar panels. On average, for every square foot of roof you can generate about 15 watts of energy. A Photovoltaic (PV) solar panels have a wattage from 150 watts to 370 watts per panel. These are what’s most commonly used by households.
Other factors that will affect this include where you live, the season and the available sunlight.
It’s worth noting that these are averages and vary widely. Someone in Texas is going to need less roof space than someone in Alaska.
To work out your requirements, this is where a calculator comes in handy. To make it easier to do the math, check out our solar panel calculator here.
To Summarize: The 7 Critical Factors To Check When Fitting Roof Solar Panels
So if you have a structurally sound roof, that’s of suitable size, with wonderful light and the right pitch, then you are well on your way to producing your own renewable energy.
If you would like to see how the leading roof solar panel contractors compare against each other click on the link at the bottom of the page.