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Insulation: Complete Guide


Home and business owners in Toronto and the rest of Ontario should insulate their homes for indoor comfort. Toronto, ON has a humid continental climate characterized by cold winters and warm, humid summers. Winters in Toronto, as is the case with the rest of the province, usually have sub-zero temperatures with frequent snow. Winters sometimes feature cold snaps with temperatures below −10 °C and sometimes as low as −25 °C. Snowstorms mixed with rain and ice are also common. On the other end of the spectrum, summer daytime temperatures are usually above a comfortable 20 °C and sometimes rise above 30 °C. Autumn and spring are transitional seasons with generally cool or mild temperatures with alternating wet and dry periods.

Insulation will keep the temperature in your house or business premises at desired levels all year round. Insulation will retain heat during cold Ontario winters and keep the temperatures cool in the summer months. You will not need to rely on cranking up your HVAC unit and fans or extra blankets. There are several other reasons why insulation is important.

Lower Energy Bills

Insulation keeps your property cool during summers and warm during winters by reducing air leaks. Although you will still need an HVAC system most of the year, you will not need to crank it up. This leads to reduced energy bills, keeping in mind that an uninsulated or under-insulated property loses between 20% and 30% of its energy.


With proper insulation, you will not hear someone snoring in the room above you. You can take your power nap while children are playing and when the TV or radio is blaring in the adjacent room. Soundproof insulation materials help absorb the sounds that bounce off the walls and floors. This insulation also protects your property from noise from the outside (neighbours, traffic, sirens).

A Healthy Home

There has been an increase in public focus on the promotion of general well-being beyond simple health over the recent past. Your insulation can contribute to the health and wellness of your property – or detract from it. While no insulation product can ensure that your property is healthy by itself, air sealing and insulation are an important component of the whole-building strategy for a healthy property. Insulation prevents mould and mildew growth by managing moisture.

So, how do you ensure that your insulation material choice is healthy? When using fiberglass, cellulose, and mineral wool insulation, confirm that the material does not contain toxic fire retardants. Use materials like formaldehyde-free fiberglass that do not have Volatile Organic Compounds (VOCs).

Going Green

Whether you are considering solar water heating, installing solar panels, installing heat pumps or any other green energy solutions, insulation is the first step to going green because it reduces your energy consumption significantly and reduces power plant carbon dioxide emissions. Insulation allows you to maximize the use of natural resources and prevent energy wastage. Without proper insulation, you will end up buying far more powerful systems to cover the home’s energy needs.

Increased Resale Value

Homeowners today are more demanding. A home that is insulated will be in greater demand compared to one that is not. Home heating and cooling costs and energy-efficient appliances are some of the features homeowners consider to be “very important” in environmentally friendly homes.

Types of Insulation

There are different insulation materials to choose from. The choice depends on the intended results, the area of application, and your budget.

Foam Board Insulation

Foam board insulation is a popular alternative to the more common fiberglass batt insulation. It has a higher R-Value per inch of thickness compared to fiberglass. Other benefits are its resistance to moisture and its easy workability. Polyethylene foam is lightweight and durable.  The closed-cell material has excellent vibration and shock-absorption properties, it is chemical corrosion resistant, tear-resistant, has non-dusting capabilities, it is very strong, and it has a high load-bearing capability. Polyethylene foam is also odourless, CFC-free, and has excellent buoyancy.

Foam board comes in sheets, with the standard-size size being 4×8 sheets – smaller sizes are also available. They also come in different thickness options, from 1/4 inch to 2 inches. You can also make a special order for thicker foam board insulation. There are different types of foam board insulation.

Expanded Polystyrene (EPS): This is the same stuff you find in disposable coffee cups and packaging for fragile items. It has an R-value of 4 per inch of thickness and is the cheapest foam board insulation available. This foam board insulation is used:

  • Over foundation walls
  • Under roofing
  • Beneath siding

Extruded polystyrene (XPS): Extruded polystyrene is rigid insulation with a higher R-value of 5. XPS is denser than EPS and is available with tongue-and-groove or straight edges for limited air movement. Although more expensive than fiberglass, you get such benefits as easy installation with no special equipment requirement (making it ideal for DIY installation).

Styrofoam™ is a popular trademarked type of XPS. This polystyrene foam insulation is lightweight and has excellent shock absorption and insulation properties. Styrofoam insulation is also great as a waterproofing agent and can work as a secondary barrier, preventing groundwater leakage. It majorly consists of trapped air bubbles (98%) which trap air inside, giving it great convection and poor conduction properties and consequently effective insulation. The major applications of Styrofoam insulation are:

  • Wall insulation (including basement walls)
  • Floor and roof insulation
  • Concrete foam insulation
  • Soundproofing
  • Exterior insulation

Fiberglass Insulation

Fiberglass insulation was first used in the 1930s. Fiberglass is made of plastic reinforced by extremely fine glass molten into fiber with a coating of liquid binder and is usually pink in colour. It comes in different insulation types, namely batts, rolls, and loose-fill. Loose-fill or blown-in insulation is blown into hard-to-reach areas, unfinished attic floors and walls, wall areas, and wall cavities using special equipment. Batts and rolls fiberglass (also called blanket fiberglass insulation) is laid out flat and fitted between beams, joists, and studs. Fiberglass batt has a slightly higher R-Value compared to standard batt.

Fiberglass insulation works by slowing the spread of heat and cold and can be used in both residential and commercial buildings. It also has soundproof properties. It does this by trapping pockets of air. Fiberglass is versatile – you can reach the desired R-Value by simply increasing the quantity of material.

So, what is the difference between batt, rolls, and loose-fill fiberglass insulation? During the manufacturing process, the cooling glass fibers fall onto moving conveyor belts and pile up into a tangled mess. This tangled mess is then cut into the desired lengths and widths called batts. These come in different thicknesses, generally from 3 to 6 inches. The major difference between fiberglass roll and batt insulation is in their size. While batt insulation is installed in varying pieces, fiberglass rolls are larger and are meant for installation between ceiling and wall framing. If loose-fill fiberglass is required, then a binding agent is not used in the manufacturing process.

Fiberglass still reigns supreme because it is inexpensive. However, the small particles that make up fiberglass can lodge into skin pores, causing rashes, itchiness, and irritation. These particles, when inhaled, can cause different respiratory ailments, including nosebleeds and coughs. Other reasons why people are moving away from fiberglass are that the material traps dust, moisture, and allergens. Fiberglass allows some airflow and is therefore, not 100% efficient as an insulator, particularly when wet. Common uses for fiberglass are:

  • It can be fitted between joists, studs, and beams
  • It can be placed in unfinished walls, ceilings, and floors

Spray Foam Insulation

As the term suggests, spray foam insulation is used to fill gaps and seal open seams. It comes in liquid form and is sprayed into position using pressurized cans. Spray foam insulation uses are:

  • Single-component spray foam insulation is used to air-seal a house before using another type of insulation
  • Two-component sprays are used to fill the spaces between joists, rafters, and studs even in the absence of other types of insulation

Two-component spray foam insulation is made up of two liquid components that are mixed at the application nozzle. When they come together, they form a chemical reaction that transforms the liquid into a highly adhesive and expansive foam.

Spray foam insulation gives you a higher R-Value and better air scaling compared to batt and loose-fill insulation. Closed-cell spray foam has an R-Value of 6 or more, while open-cell spray foam has an R-Value of between 3.6 and 4.3. Closed-cell spray does not absorb water. Spray foam’s major disadvantage is the higher price.

Stone Wool Insulation

Stone wool insulation is made by spinning molten rock and minerals with recycled steel slag for cotton-candy-like insulation. The insulation is then pressed into rolls and sheets. Stone wool insulation is installed like batt insulation into wall cavities. You can go for flexible or rigid options.

A popular example of stone wool insulation is rockwool insulation. Here, the stone used is Basalt rock, which is an abundantly available volcanic rock. The steel slag used is a by-product of the steel and copper industries.

Rockwool insulation benefits include thermal and sound insulation. The insulation is popularly used as a firestop between floors as it retains heat and traps air, thereby slowing down the transfer of heat. It can withstand up to 2,150 degrees Fahrenheit without smoking, melting, or catching fire. The batts are friction-fit into place (stapling is not necessary). The material is water repellent and allows moisture to escape, deterring mould and mildew growth. Common uses include:

  • Rockwool insulation can be used in the place of fiberglass, including on walls, ceilings, floors, crawlspaces, and attics
  • It is ideal for rooms along the cold north sides of a property
  • The sound deadening feature makes it ideal for music studios and media rooms

Note that rockwool insulation is only available un-faced (with no foil or kraft-paper barrier). It is, therefore, necessary to install an independent permeable membrane as a vapour barrier. Rockwool’s R-Value (3 to 3.3 per inch of insulation) is higher than that of fiberglass.


Cellulose has an R-Value of between 3.6 and 3.8 per inch of insulation. It is made up of recycled newspaper that then undergoes borate treatment to make it fire resistant. Boric acid is also insect and rodent resistant.

Once the paper undergoes borate treatment, it is then compressed into large bales. There are 3 primary methods of applying cellulose insulation:

  • Cellulose can be blown into place, just like with loose-fill fiberglass
  • Dense-pack cellulose can be blown into an enclosed ceiling and wall cavities
  • Lastly, wet-spray cellulose is made up of cellulose mixed with a liquid binder and can be used for open stud bays

What kind of insulation is the most eco-friendly?

Insulation allows you to go green by reducing your heating and cooling requirements. The energy required for heating and cooling has associated emissions which are bad for the environment. You can further ensure that the insulation option you are using is green by going for recyclable and other eco-friendly insulating materials. Below are the most eco-friendly insulation materials:


Cellulose is one of the most environmentally friendly insulating materials since it is made up of between 80 and 85% recycled/shredded newsprint. The remaining 15% consists of borax, ammonium sulfate or boric acid for fire resistance. The boric acid component in cellulose is not only a fire retardant, but is also an insect repellant. It is also antifungal and non-toxic. Cellulose insulation is usually locally produced, minimizing the emissions associated with transportation.

You will not be compromising on insulation with cellulose insulation, as the material has an R-Value of 3.5 per inch of insulation, which is similar to fiberglass. Just like spray foam, cellulose is a loose-fill product that is blown into place using a specialized machine. This allows you to fill the smallest holes, increasing insulation levels. Cellulose is, however, sensitive to moisture, meaning it is not a good option for damp environments such as damp basements.

Spray Foam Insulation

Spray foam has an R-Value of up to 6.5 per inch of insulation, making it one of the most efficient insulation materials on the market. The high R-Value, and the fact that it is blown into place, means you don’t need too much material to achieve the required R-values.

You can also get spray foams that are not petroleum-based. There are spray foam insulations made of polyurethane and from soy or vegetable oil.

Stone Wool Insulation

Stone wool (or mineral wool) insulation, like Rockwool insulation, is made up of molten stone and steel slag. The rock used in Rockwool (Basalt rock) is readily available. The steel slag is a byproduct of the steelmaking process, meaning you will be helping prevent this steel slag from being discarded.

Can insulation be recycled?

People looking to recycle or reuse insulation usually do it for two reasons: to save money and to save the environment. Insulation material is used in big quantities. Recycling and reusing ensure the insulation does not end up in a landfill and is a way of going green since less insulation will be produced in the first place. Below are recyclable and reusable insulation materials.


When cellulose is installed by a professional, it can be completely recovered and reused, leaving almost zero waste. During the installation process, blow-in machines allow extra materials to be vacuumed up for future use or to be brown back in, reducing wastage.

Cellulose is made up of 80 to 85% recycled paper, which has undergone borate treatment for fire retardation. The borate treatment is non-toxic, making it safe to handle during the reuse. Other than the fact that you can reuse cellulose, this is also the greenest option because the paper used for cellulose raw materials is usually consumer paper products. These paper products are tied to responsible forestry management and renewable resource of tree plantations. It takes less energy to produce cellulose compared to other insulation materials. Another reason cellulose is a green option is because the material is produced locally, meaning lower transport-related emissions.

Note that although cellulose is made from recycled materials, it cannot be recycled because of the fire-retardant materials used to make it. So while the material can be reused and is environmentally friendly for the most part, it is not recyclable.


Fiberglass insulation can also be reused after the initial installation and is also recyclable. Fiberglass can be easily removed in whole pieces since it is installed in batts, allowing for reuse, and it can be easily reclaimed from demolition debris and recycled.

However, you have to ensure the fiberglass is not compromised before you reuse it. Moisture in fiberglass will breed bacteria and mould, which will reduce its insulation abilities. You should not use fiberglass that is matted down or compressed as it will not give you the desired R-Value, moisture control, and/or thermal effectiveness. Like cellulose, it takes a professional’s experience, skills, and equipment to properly remove fiberglass for reuse or recycling.

You should never be tempted to leave recovered insulation material by the roadside as this could lead to hefty fines. Contact your local waste management facility to learn about recycling protocols for insulation materials.

How much will you save by adding insulation?

One of the greatest benefits of insulation is that it keeps your energy bills down. Insulation saves you money on energy bills because it reduces the rate at which heat is flowing. Insulation keeps warm air inside during cold winter months and hot air out during hot winter months.

Without good insulation, your HVAC system will be on overdrive, and this will lead to higher energy consumption and, consequently, higher energy costs. US Department of Energy statistics shows that 49% of a home’s energy bill is spent on cooling and heating. EPA statistics show that you can save as much as 15% on the cost of heating and cooling if you add insulation in the attic, crawl spaces, and basement rim joists. This saving is higher by 20% in cold regions like Ontario. Another monetary benefit of insulation is that it increases the resale value of your home.

So, exactly how much do you save when you insulate your home? It is difficult to get an exact figure because different factors have to be considered, including climate, the HVAC system in use, the square yardage of the home, and many others. However, there are online estimate tools that can give you a good estimate. An experienced professional can also give you an estimate.

Cellulose Insulation Manufacturers Association (CIMA): This is an online calculator that calculates your yearly savings. You enter such data as the size of your house, the current R-Values of the insulation, the heating degree days, and the fuel type (natural gas, fuel oil, electricity, or propane). The tool will then give you how much you expect to save with insulation this year as well as over the next 10 years (assuming 10% increase in fuel cost per year) as well as expected greenhouse gas reduction (with an assumption that a coal-fired power plant is used if the fuel type is electricity).

Home Energy Saver: Home Energy Saver tool is another energy bill calculator that calculates energy bills based on your current energy rates as well as such personal information as where you live, the year your house was built, the number of people in your home, the type of HVAC system in use, and whether you have a basement. The tools give you the current yearly energy costs as well as how much you stand to save with upgrades.

Other than installing attic installation and wall insulation, other ways to reduce your energy bills are:

  • Broad-based energy conservation approach: Other than insulation, go for other energy-efficient solutions such as repairing/replacing old and leaky windows and getting rid of incandescent bulbs in favour of CFL bulbs for comprehensive energy efficiency.
  • Air sealing your home: Insulation is not enough for an energy-efficient home since it cannot possibly cover all possible air leakage areas. Air sealing techniques like weather stripping and caulking ensure all possible air leakage areas are covered before insulation.
  • Engaging a professional: A professional will install your insulation properly to prevent air leakages. A professional will also advise you on the best insulation options for your Ontario home.

How Does Air Sealing Work and Why is it Important for an Insulation Project?

Air leakage is a phenomena where during cold weather, outside air enters the home through cracks and around doors, windows, and other openings and an equal volume of conditioned air leaves the house uncontrollably through a convective action. This is called the Stack Effect.

Why Air Sealing is Important for an Insulation Project

Other than making your home uncomfortable due to drafts and cold spots, air leaks also lead to increased energy costs since the HVAC system will need to be cranked up due to the loss of conditioned air. Air leakage also causes moisture problems that can affect the structure’s durability and the occupants’ health. To curb air leaks, you must first detect them. The most effective ways of doing this are:

  • Visual inspection: Check exterior doors and windows, attic hatch, baseboards, electrical outlets & switch plates, and fireplace dampers, and you will be surprised how many cracks and gaps can be easily spotted.
  • Building pressurization: A home auditor can do blower door tests to pressurize the house for leaks that are hidden behind floors, ceilings, and walls to be easier to find. Home auditors point infrared cameras to observe how smoke (generated by smoke pencils) swirls, which points to the exact source of the leak. They then seal the leaks on the spot.

How Air Sealing Works

For cracks and openings that are visible to the naked eye, simply use foam or any other type of sealant on the spot. There are several other proven methods of air sealing to prevent air leaks. You should engage a professional for the best results.

  • Weatherstrip and caulk windows and doors that allow air leakage
  • Caulk leaks where electrical wiring, plumbing, and ducting come through walls, ceilings, floors, and soffits over cabinets
  • Install foam gaskets behind switch plates and outlets on walls
  • Use double-pane, low-emissivity windows in place of single-pane windows
  • Ensure the dryer vent is not blocked, which not only saves energy but may also prevent a fire
  • Replace exterior door thresholds and bottoms with ones with pliable sealing gaskets
  • Tightly close the fireplace flue damper using an inflatable chimney balloon if it is not in use
  • Use furnace cement caulk and sheetrock, sheet metal, or other fire-resistant material to stop air leaks around furnaces, gas-fired water heater vents and fireplace chimneys
  • Use rubber door sweeps at exterior doors’ thresholds

What is R Value and How Does it Work?

What is the R-Value?

R-value (Resistance Value) is a rating for the efficiency of insulation. The higher the R-Value, the better the insulation’s ability to resist heat flow. The value depends on the density, thickness, and constituent materials in the insulation.

How does R-Value Work?

Heat transfer occurs through conduction, convection, and radiation. Fibrous, permeable insulations like fiberglass slow down conduction, delaying heat transfer, while spray foam and rigid foam insulations not only slow down this conduction but also limit heat transfer through convection.

R-Value is measured per unit length. The thicker the material, the more heat resistant it is, and so values are listed per inch. You can then multiply the value with the thickness of the specific insulation you are using. R-Values of common insulation materials are 3.7/inch for blown-in cellulose, 3.14/inch for fiberglass, and 4/inch for EPS.

On the packaging of the insulation material, you will get a nominal R-Value which tells you the thermal resistance you will get per inch of the material. However, you should work with the effective R-Value in the real world, which considers other factor such as temperature, aging, moisture accumulation, and installation.

Provincial building codes in Ontario and other provinces in Canada specify a minimum R/RSI value for new construction. Canada is divided into 4 zones for recommended R-Value purposes, namely ZONE A, B, C and D. Ontario falls under ZONE A and B. The R-Value recommendation for Ontario is from R30 to R40 for walls, R30 to R40 for basement walls, R45 to R60 for roofs and ceilings, R60 to R80 for attics, and R35 to R45 for floors (over unheated spaces).

How Much Insulation Do I Need for My Project?

The thickness of the insulation you need for your project depends on the recommended R-Value and the nominal R-Value of the material you are using. The R-Value of the attic will be different from that of the basement. The total amount of material you need depends on the surface area you intend to cover (cumulative length x height of all the rooms). You then need to multiply this by the number of layers of insulation you need.

Depending on where you live in Ontario, you will either be in ZONE A or ZONE B, with ZONE A climate being warmer than ZONE B. Each zone has a specific recommended R-Value, such as an R-Value of R45 to R50 for roofs of houses in ZONE A.

The R-Value is measured per inch of the insulation material. For example, if you are using XPS with an R-Value of 5/inch of insulation and you want to achieve the recommended R-Value of R45, you will need 9 (45/5) inches of the insulation.

When calculating the surface area (Length x Height), remember to factor in the spacing of the studs. Insulation materials come in precut lengths and standard rolls made to fit in precisely between studs. Do not subtract window and door openings, as these amounts will make up for nonstandard framing distances and odd cavities.

Once you have calculated the square foot requirement, divide the value by the square footage indicated on the packaging. Check carefully since different manufacturers have different dimensions/sizes of insulation. The number you get is the number of bundles/rolls you need to insulate your home.

At Bernardi Building Supply, we have been supplying Ontario residents with installation materials for over 50 years. We stay on top of the ever-evolving construction industry by supplying the latest insulation products from the best manufacturers in North America.