How Sun's Heat Affects your Roof’s Energy Efficiency in Saskatchewan.
Are you ready to replace your roof? In Saskatchewan, where temperatures can fluctuate wildly through the seasons, your roofing material choices can greatly impact your energy costs, maintenance needs, environmental impact, and future replacement. This blog will discuss how heat affects different roofing materials and the best materials for overall efficiency.
Dark roofing materials absorb more solar radiation.
Solar radiation can change the temperature of your roof by a huge margin. On a dark asphalt shingle roof, the temperature can be more than 15℃ hotter than the outside temperature. In many homes, that heat is absorbed into the attic and home. If you don’t have central air, increasing your home's temperature can be dangerous and uncomfortable–especially without adequate ventilation; if you have air conditioning, it must work harder to keep you cool, which increases the cost of your electrical bill.
Air conditioning is a huge driver in creating hotter cities and has a detrimental effect on the environment through energy consumption and heat output. You can save money by reducing your home's energy consumption, and it starts with choosing the right roofing material.
Traditional asphalt shingles are typically the biggest heat absorbers of all the potential options for roofing materials. When your roof is ready for replacement, this is a great time to choose the best material that can save you money for its lifespan.
What is the Solar Radiation Index?
This measurement from 1-100 is used to rate roofing materials based on their reflectivity. Roofing materials with a high SRI rating are more energy efficient and sustainable than their lower rating counterparts. The SRI of a material is based on its solar reflectivity coupled with its capacity for thermal emittance. This metric helps determine the effectiveness of material and allows the consumer to make informed choices about their home.
The potential downsides of choosing a cool roof in Saskatchewan.
While a cool roof has several benefits, such as reducing the need for air conditioning and reducing overall city temperatures, there are some pitfalls. In Saskatchewan, temperature differences can make it difficult to decide which season to prioritize in your quest for energy efficiency. In the winter, a darker and less reflective roof can make heating your home less energy-intesive but can also drive up the interior temperature over the hot summer months. You can increase the overall efficiency of your home by:
Increasing your home’s thermal mass
Replacing your old doors and windows
Utilizing blinds in the summer months over the south and west-facing windows
Increasing the air circulation in your home
Incorporating passive solar heating into your new build
Replacing your insulation with sustainable and high-performance options such as wool, cellulose, cork, and even mycelium
Which roofing material should you choose for energy efficiency?
Metal roofing Metal roofing provides a high SRI rating, especially when you add a reflective coating. However, it maintains a relatively low thermal emittance level, so it’s a great roofing material for a complex climate like Saskatchewan’s. It can be cut to resemble other common roofing materials like wood shake or tile but is easier to maintain. While metal roofing can be an investment, its lifespan is worth considering. Metal roofing can last up to 70 years compared to asphalt shingles which have an average lifespan of 15-30 years.
Asphalt Shingles While this is a common and affordable roofing material, it is one of the most heat-absorbant roofing materials regardless of colour. In addition, these petroleum-based tiles have a shorter lifespan than many of their counterparts, making them a favourable initial investment but an altogether unsustainable option long-term. Asphalt shingles can bring heat into your home over the winter months, but they will also contribute to the high cost of cooling your home over the summer. In Saskatchewan, it’s hard to say which is the lesser of the two evils as our temperature fluctuations are extreme. You can reduce the heating effect of asphalt shingles by ensuring your attic is well ventilated and choosing new and energy-efficient technology and recycled products when upgrading your roof.
Green Roofs While these are slow to trend in Saskatchewan, green roofs are a potential future option for homeowners––especially those interested in long-term sustainability. The challenges for green roofs can be numerous, so research is necessary. Building a green roof or roof-top garden is an especially good option if you are building a new home or outbuilding, as the structural components should be considered from the outset.
Wood shingles and shakes These redwood shingles have a long lifespan of 30-50 years, making them an aesthetically pleasing and sustainable choice for homeowners. In addition, they also boast a decent SRI rating, especially when combined with light-coloured reflective coatings. However, wood shingles require more maintenance than other roof types and are harvested instead of recycled. Calculating longevity, cost, and sustainability are key when considering which material is right for your home.
Rubber EPDM This white rubber membrane is ideal for a flat roof and has one of the highest SRI ratings of all the readily available materials. It is most often used in apartments, and commercial buildings, where a flat roof is more common and energy efficiency and long-term durability are necessary considerations.
Slate Roofing Slate is the ideal roofing material for our climate. However, it is both heavy and an investment. While the lifespan of slate roofing can reach upwards of 100 years, the initial investment and local availability can make it a difficult choice to justify. This material is highly insulating, providing cool temperatures in the summer months and effective warmth in the winter. If you choose slate roofing, your home must be evaluated for weight before installation, as this product is as heavy as it is durable. If you plan to build a new home, this is the best time to consider this material.
Your environment can affect your roof and your home.
While our climate is extreme, you can count on the experts at Ozmun Roofing to help you select the best material for your unique concerns and budget. From high-efficiency roofing materials to roof repair, we are your local roofing experts. Reach out to us today to learn more about the best materials for your home.