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5 min read

How to Insulate an Attic


5 min read

How to Insulate an Attic

InsulationInterior renovationsHow to Insulate an Attic

The attic is one of those parts of the house that we tend to forget. Like they say, out of sight, out of mind. Yet the things that go on up there can end up having a concrete effect on numerous elements that affect us on a daily basis. To gain a better understanding of how important attic insulation is, has prepared a brief presentation on the subject:

First, it is important to note that different kinds of attics exist. In some houses, the attic is set up into a livable space, with rooms and windows. For the sake of this article, however, we will be concentrating on attics that are more difficult to access. In most houses, these attics are reached through a trap door in the top floor ceiling.

Others are accessible through an opening on the outside of the house. It can be hard and even impossible to get into the attic. Some have ceilings that are too low (less than one meter in height), whereas others are blocked by architectural elements. If such is the case in your house, you will have to do business with a professional contractor at every step of the process.


How to inspect your attic

inspection de l'entretoit

Source: Canva

An attic should be inspected on a regular basis, in order to detect any worrying signs before they are able to turn into real problems. Pay special attention to the condition of the roof framing. If you notice the smell of mould, try to find the source of this smell. 

Also, check to see if there are any water leaks. The insulating product that covers the surfaces should be dry and firmly held in place. If it sags in certain areas, you’ll have to find a way to put them back into place.

Beware: if your insulation material is made with vermiculite, DO NOT TOUCH IT. Vermiculite may contain asbestos. Hire a qualified inspector. For more info, check How to recognize lead and asbestos in your home

Make sure that the ceiling on the top floor of your home has a vapour barrier. Most modern houses are equipped with this type of insulating material. However, such is not the case in older buildings. If you live in an older house, you should get in touch with a contractor to ask for their advice. In some cases, a few layers of vapour-barrier paint on the top-floor ceiling could do the job, provided that you also make sure that the openings in the ceiling are well sealed.


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How to improve your attic’s insulation

inspection de l'entretoit

Source : Canva

First of all, it is important to know that if you have noticed any problems with mould, you have to solve this situation before you add any other insulation material. It may indicate a problem with the ventilation system, which is normally supposed to regulate the humidity level.

Unfortunately, it is impossible for us to give more precise information on this subject. Each case is very different; therefore we suggest that you call or get in contact with a contractor who will be able to find the best solution to fix your situation.

There are many different reasons to improve your attic’s insulation, the main one being that this will help protect the building in which you live. The effects of these renovations will also be felt on your heating and electricity bills. Therefore, do not neglect this very important part of your house.

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Roof insulation: what to know


Materials used for roof insulation and their prices

There are several options available to insulate your roof. First of all, you can opt for blown-in cellulose which offers an insulation degree of R-3.7 per inch of thickness. The main advantage of cellulose is that it can slip into crevices, which makes it very efficient. There are a number of other advantages, such as the low cost, the resistance to fire, the soundproofing qualities and the way it manages to control humidity. Since it is rather hard to install, it is best to hire a professional to do so. The average price for blown-in cellulose is $1/square foot. 

As with blown-in cellulose, blown-in fibreglass can fill all the space inside the roof. However, its degree of insulation per inch is lower and only reaches 2.85 per inch of thickness. It must, however, be noted that it is better for thermal insulation than batt insulation, whilst also being resistant to fire and humidity.The average price for blown-in fibreglass is $1/square foot.

Lastly, you can also choose batt insulation (fibreglass or rock wool). This material has an insulation factor of R-3.3 per inch of thickness. It is resistant to fire, humidity, mould and parasites. It also provides a good energy performance in addition to having a good price/quality ratio. The average price for batt insulation is $1,20 /square foot.

Note that there are other options for insulation materials, such as hemp, polyurethane and expanded cork.

To learn about the average prices of insulation materials, check out our article The cost of insulation


The importance of proper attic insulation

If the attic ventilation is not optimal, this will affect the building’s energy performance. It could also have a negative effect on the house’s occupants. In a house that is properly insulated, warm air (or the cool air coming from air conditioning) is well confined inside the house.

Roof insulation is extremely important as it helps to: 

  • Benefit from a comfortable room temperature inside the house;
  • Reduce your consumption levels for air conditioning and heating;
  • Reduce your electricity bill.


The benefits of proper ventilation on air quality

inspection de l'entretoit

Source : Canva 

If you have problems with the house overheating and that your air conditioner works hard during the summer, the potential sources are numerous, but here are a few leads:

  • Attic ventilation may not be adequate
  • The soffit is sometimes blocked by the insulating material.
  • The ventilation can also be affected by dirt and dust build-up.

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Last modified 2023-10-19

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5 min read 07 Sep 2023

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8 min read 19 Jul 2023

How to Effectively Insulate Your Garage Door

Wall, door, attic, and foundation insulation, not unlike window caulking, aren’t the sole factors influencing your home’s energy efficiency. Garage doors, which are too often overlooked, allow warm air to seep out, along with a part of your savings. While heating a garage isn’t mandatory, having a well-insulated door is a non-negotiable benefit. If you’ve started inquiring about the matter, you were most likely recommended insulated garage doors. However, before moving ahead and changing your garage door, take a moment to read this article. We’ll detail how to easily and swiftly improve your garage door insulation, all that at a bargain! What type of insulation should be used for a garage door? 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6 min read 20 Sep 2023

What Are the Insulation Standards in Quebec?

It’s common knowledge that insulating a house will have a significant impact on the overall comfort of the ambient temperature as well as the building’s energy efficiency. While our energy expenses may set us on the right path to knowing whether our home is properly insulated or not, there’s a way more accurate way to find out, and that’s by relying on insulation standards and calculating the energy efficiency of different materials. Quebec’s Insulation Standards: A Regulation to Better Oversee Work Carried Out Source: Canva Since 2012, the Quebec Construction Code has imposed new standards for matters related to energy efficiency and ventilation. Homes that meet these requirements make it possible for homeowners to significantly save while enjoying better air quality and improved comfort. Insulation requirements have been made more stringent, especially for buildings located in colder climate zones. 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Rigid panels will be installed up against the concrete walls or batt insulation will be inserted between the structure’s studs held against the foundation walls. NOTE: Fibreglass insulation should never come into contact with concrete! The best product to insulate rim joists and a concrete foundation (basement or crawl space walls) is often a spray-applied polyurethane foam. This type of insulation must be covered by a gypsum panel post-application. A few exceptions or clarifications: A foundation wall that cloisters a heated space from a non-heated space, from outdoor air, or adjacent ground must have an overall thermal resistance of R-17.0, no matter where the building is located. A foundation wall with more than 50% surface exposure to outdoor air, as well as a part of a wood foundation wall, must have a total thermal resistance (RSIt) equal to that required for above-grade walls (R-24.5). A wood foundation wall must be insulated just like an above-grade wall would be, no matter the surface area exposed to outdoor air. For composite foundation walls, the percentage of surface space exposed to outdoor air has to be calculated for all parts of a wall, and the RSIt value will apply solely to that specific part. Are you looking for experts for your insulation-related project? Fill in our form to be connected with top-rated contractors! What’s the best R-value to properly insulate a home? Source: Canva An R-value—or its metric equivalent: RSI value—is a material’s thermal resistance coefficient. The higher the R-value, the more effectively a specific material will be able to impede heat flow, which is what defines thermal resistance. When referring to insulation, we often tend to forget that the total R-value accounts for the whole of the materials present in the building’s composition, rather than solely the ones considered in the “insulation” material category. Most building materials like wood, concrete, exterior siding and cladding, plaster, etc., have a significant impact on thermal performance, no matter how small it might be. When considering a house as a whole, it’s currently recommended to opt for an 80 Energuide rating with air barrier certification. Using the current building methods (concrete walls poured into an insulated form, spray polyurethane foam, etc.) makes reaching an 84 Energuide rating possible, 90 even, while also ensuring a permanent air barrier. What’s the R-value of insulation materials? When it comes to insulation, the chosen material is key. While almost all insulation materials can be put to the test in new constructions—as long as it was planned ahead of time—with residential renovations, the four most commonly used insulation types are loose-fill, batt, rigid panels, and spray foam. Here’s a list of thermal resistance coefficients for various insulation materials: Insulation materials Thermal resistance value Fibreglass or mineral wool R-3.5 Rockwool R-4.0 Extruded polystyrene (type 2-3-4) R-5.0 Expanded polystyrene (type 2) ≈ R-4 Polyurethane (type 1) ≈ R-5.2 per inch Polyurethane (type 2) ≈ R-6 per inch Polyisocyanurate (PIR) ≈ R-6 per inch Cellulose insulation ≈ R-3.5 per inch Blow-in fibreglass ≈ R-3 per inch Straw ≈ R-35 per bale Cotton ≈ R-3.8 Wood fibre ≈ R-3.3 Spray polyurethane foam ≈ R-6 Half-inch HD fibreboard ≈ R-1.5 7/16 inch OSB panel ≈ R-0.7 Gypsum ≈ R-0.44 Ensuring the Thermal Efficiency of a Building Source: Canva In Quebec, the thermal resistance standards to meet, when it comes to a new building or extending an existing structure, obviously differ. In most municipalities, these values add up to R-41 for roofs, R-24.5 for above-grade walls, and R-17 for foundation walls. Although we previously stated the recommended energy efficiency, a regular house will typically have an R-value ranging between 30 and 50. (For new homes, this number will increase to R-60.) During a renovation process, reaching such targets is often very challenging—maybe even impossible. However, homeowners should still aim for these figures, especially if their heating expenses are rather high. Quebec’s Insulation Standards: Ensuring Sustainable and Comfortable Buildings Quebec’s insulation standards, as stipulated by the Construction Code, play a vital role in building sustainable, comfortable, energy-efficient structures. These ensure buildings that: Resist Quebec’s harsh weather conditions Minimize energy loss And provide pleasant indoor environments These standards result from careful consideration with the goal of improving the quality of life for citizens while also contributing to limiting the carbon footprint. As such, by adhering to current standards, we’re not only fulfilling legal construction requirements but we’re also making a tangible step toward a future built on preserving the environment.

7 min read 20 Sep 2023

What Are the Different Ways to Insulate a Garage Ceiling?

A garage ceiling can be insulated using several types of insulation materials. If you’re having a hard time wrapping your head around which ones, rest assured, you’ve come to the right place. In this article, we compared 14 different materials based on their thermal characteristics. So not only will you find the most insulating materials, but you’ll also find those that are most compatible with the insulation method that you may want to carry out at home. How to Choose the Best Insulation Material for a Garage Ceiling Source: Canva To figure out which insulation materials are best for a garage ceiling, we looked at 14 different materials based on the following 5 thermal characteristics: Thermal conductivity (K-value) Thermal resistance (R-value) Diffusivity Effusivity Thermal lag (in hours) Before we get ahead of ourselves, here’s a list of the best garage insulation materials: Rank Material 1 Polyurethane (latest technology) 2 Extruded polystyrene (common) 3 Expanded polystyrene (common) 4 Cork (natural) 5 Rockwool (loose-fill) 6 Polyurethane (common) 7 Expanded polystyrene (high-density) 8 Expanded cork 9 Rockwool (medium-density) 10 Expanded cork (loose-fill) 11 Extruded polystyrene (XPS HFC) 12 Extruded polystyrene (XPS) 13 Expanded polystyrene (medium-density) 14 Rockwool (low-density) Now, let’s take a closer look at the different insulation material values: R-Value (for an 8-inch thickness) An R-value stands for a material’s thermal resistance coefficient and is based on two factors: Thickness Thermal conductivity A material’s thermal conductivity is quantified by a numerical value, and the lower that value is, the better the material’s insulation properties are. However, thermal resistance, measured by the R-value is quite the opposite: the higher the R-value, the better the insulation performance. Rank Insulation material Conductivity R-value 1 Polyurethane (latest technology) 0.025 8.05 2 Extruded polystyrene (common) 0.031 6.5 3 Expanded polystyrene (common) 0.035 5.7 4 Polyurethane (common) 0.035 5.7 5 Expanded polystyrene (high-density) 0.040 5 6 Expanded cork (loose-fill) 0.040 5 7 Cork (natural) 0.040 5 8 Extruded polystyrene (XPS HFC) 0.040 5 9 Extruded polystyrene (XPS) 0.042 4.8 10 Rockwool (medium-density) 0.044 4.55 11 Rockwool (low-density) 0.050 4 12 Expanded polystyrene (medium-density) 0.052 3.8 13 Rockwool (loose-fill) 0.060 3.3 14 Expanded cork 0.090 2.2 Are you looking for experts for your insulation project? Fill in our form to be connected with top-rated contractors! Thermal Diffusivity and Effusivity Thermal diffusivity and effusivity are significant thermal properties to consider when choosing an insulation material meant for a garage ceiling. By selecting a material with decent thermal properties, you’re in turn ensuring that your garage is efficiently insulation and safeguarded. Thermal diffusivity Thermal diffusivity is a material’s capacity to transmit heat through conduction. An excellent thermal diffusivity is typically indicated by a value below 0.2, whereas a value exceeding 1 is considered exceptionally poor. Rank Insulation Material Diffusivity 1 Expanded cork 0.16 2 Cork (natural) 0.17 3 Expanded cork (loose-fill) 0.27 4 Extruded polystyrene (common) 0.63 5 Polyurethane (latest technology) 0.64 6 Rockwool (medium-density) 0.61 7 Polyurethane (common) 0.71 8 Extruded polystyrene (XPS) 0.83 9 Extruded polystyrene (XPS HFC) 0.86 10 Expanded polystyrene (high-density) 0.97 11 Expanded polystyrene (common) 1.20 12 Rockwool (loose-fill) 1.46 13 Rockwool (low-density) 2.20 14 Expanded polystyrene (medium-density) 2.99 Thermal effusivity As for thermal effusivity, it indicates a material’s ability to transmit heat through radiation. The lower the effusivity coefficient, the better the insulation material is. As such, a value above 1,000 suggests poor insulation capabilities in a material, while a value below 35 indicates excellent insulation properties. Rank Insulation material Effusivity 1 Expanded polystyrene (medium-density) 30.08 2 Expanded polystyrene (high-density) 30.60 3 Expanded polystyrene (common) 31.86 4 Polyurethane (latest technology) 32.49 5 Rockwool (low-density) 33.66 6 Extruded polystyrene (common) 38.97 7 Polyurethane (common) 41.41 8 Extruded polystyrene (XPS HFC) 43.08 9 Extruded polystyrene (XPS) 46.17 10 Rockwool (loose-fill) 49.72 11 Rockwool (medium-density) 56.32 12 Expanded cork (loose-fill) 76.94 13 Cork (natural) 96.18 14 Expanded cork 227.68 Thermal Lag Thermal lag refers to the time period (delay) during which an insulation material can inhibit heat transfer. Rank Insulation material Thermal lag (hr) 1 Expanded cork 16 2 Cork (natural) 15 3 Expanded cork (loose-fill) 12 4 Rockwool (medium-density) 8 5 Extruded polystyrene (common) 8 6 Polyurethane (latest technology) 8 7 Polyurethane (common) 7 8 Extruded polystyrene (XPS) 7 9 Extruded polystyrene (XPS HFC) 7 10 Expanded polystyrene (high-density) 6 11 Expanded polystyrene (common) 6 12 Rockwool (loose-fill) 5 13 Rockwool (low-density) 4 14 Expanded polystyrene (medium-density) 3 What are the best materials to insulate a garage ceiling? Source: Canva Polyurethane made from the latest technology and extruded polystyrene are, without a doubt, the best materials to insulate a garage ceiling. However, if you’re looking to solely use eco-friendly materials in your home, cork is your best bet. Learn more about the best garage ceiling insulation materials down below. Polyurethane panel or polystyrene panel? It all depends on the quality of the polyurethane material. If you come across polyurethane with a thermal conductivity of 0.026 rather than 0.035, it indicates that it’s a cutting-edge polyurethane technology; it’s more efficient than a polystyrene panel. Otherwise, polystyrene will be a way better insulation material. Moreso because you can choose extruded polystyrene, or even better yet, expanded polystyrene. Polystyrene and polyurethane panels have the added bonus of being aesthetically pleasing, while also cutting back on drywall use. Rockwool Mineral wools are far from the most efficient insulation, but they do have one significant advantage: their flexibility. It isn’t uncommon to see piping snaking through a garage ceiling. Therefore, rockwool is the perfect material. Since it’s very malleable, it can easily be slipped between pipes. As a result, you won’t need to install drop ceiling tiles to properly insulate your garage, which turns into significant space gain. Vapour barrier A vapour barrier is a must if your garage happens to be below a living space. Typically, the vapour barrier will be a part of the living space's flooring insulation system. Cork As we’ve already mentioned in the first part of the article: cork is an excellent insulation material for green homes. It ranks just below polyurethane and polystyrene. However, cork has two issues: Requires installing drop ceiling tiles Isn’t made for winter Therefore, if your garage ceiling is rather low, cork may not be the best insulation material. Generally speaking, in Quebec, where winters are quite harsh, cork doesn’t typically hold its own. As a matter of fact, while it does have an exceptional thermal lag in terms of heat, its thermal conductivity and resistance (R-value) are deemed average. How to DIY a Garage Ceiling Insulation Source: Canva There are three methods used to install insulation material on a garage ceiling: Glue/screws Drop ceiling (drop tiles or self-supporting membrane) Spray You can base your decision on: Your preferred method The height of your garage The insulation material you’ve selected For example, should you decide to opt for a spray-in method, polyurethane is your only option. Whereas, with a drop ceiling, you can use mineral wools, polystyrene, or polyurethane. However, using the glue/screw method, for which the polystyrene panels are typically preferred, you’ll lose a significant amount of height in your garage. Concrete Garage Ceiling Insulation Tips Source: Canva Favour the following three insulation materials: Polyurethane insulation panels Extruded polystyrene insulation panels Cork If you’re not comfortable using the glue/screw installation method, note that a concrete garage ceiling can be insulated using spray polyurethane foam.

9 min read 12 Sep 2023

How to Properly Insulate a Flat Roof

Ensuring that your flat roof is adequately insulated is a vital part of maintaining a comfortable temperature inside your home. Depending on your budget, you can insulate your roof from the inside or outside. However, to meet Novoclimat’s program requirements, you have to select the appropriate materials and correctly carry out their installation. Discover our advice for maintaining effective insulation and saving on your monthly energy expenses. Insulating Different Types of Flat Roofs Source: Canva Insulating a flat concrete roof Pouring a concrete slab onto a flat roof means benefiting from two concrete-specific characteristics: Waterproofing Diffusion resistance These qualities render the use of a waterproofing layer, like a vapour barrier, useful. However, it very much relies on whether the concrete was properly poured, meaning without any apparent cracks forming, and ensuring that the joints are adequately coated and sealed. And it doesn’t end here, as a flat roof’s concrete slab must be highly resistant to water infiltration. Should it be insulated over or under the slab? Flat roof insulation can either be laid above or under the concrete slab. When it’s laid above it, the roof itself is similar to an inverted flat roofing system. When the insulation material is laid under the concrete slab, a layer of gravel, or greenery, is added to protect the concrete from excessive temperature variations. However, when the insulation is placed beneath the concrete slab, long-term, humidity can seep in between the slab and the layer of insulation. Therefore, it’s best to also add a smart vapour barrier. The latter diffuses humidity one way while blocking it in the other. Traditional vapour barriers have limited potential to dry ambient air. As such, the moisture trapped between the layers can lead to mould growth issues. For this reason, insulating from the outside (warm roof insulation) is often preferred when working with concrete flat roofs. Insulating a timber flat roof Timber flat roof insulation can just as well be laid under or above the waterproofing layer. However, just like with concrete, it’s advised to lay the insulation material above the waterproofing layer. Otherwise, humidity-related issues can quickly arise. In fact, the matter of installing a ventilation system is often questioned and will be reiterated in further detail in the cold flat roofing system section of the article. In some countries, like England, timber flat roofs are vented. However, studies have shown that ventilating such roofs generates more humidity compared to non-ventilated roofs. This is actually the subject of a Danish study that questions the dew point. The dew point occurs when the temperature reaches the degree at which water vapour condenses and forms small droplets. The Danes have shown that a ventilated flat roof that was insulated from the inside presents humidity issues as soon as the dew point temperature rises above 11°C (52°F). Moreover, a dew point of 11°C occurs when the temperature inside a home reaches 20°C (68°F), while the relative humidity level (RH) hits 56%. Therefore, it’s best to lay the insulation material above the vapour barrier. Should you decide to add insulation above and under the vapour barrier, make sure the insulation laid beneath the vapour barrier isn’t thicker than a third of the roof’s overall thermal resistance. How to Insulate a Flat Roof for a Warm Roofing System With a warm roofing system, the insulation is installed from the outside, thereby creating a shared thermal boundary between the roof and the inside of the home. To do so, a vapour barrier is placed directly on the roof’s structure, effectively serving as the waterproofing layer. Above the vapour barrier, a layer of insulation is added, which can be made of: Rockwool Glass wool Lastly, an elastomeric or thermoplastic olefin membrane is stacked on as a top coat. Since the insulation is stuck to the vapour barrier, it further protects the structure against water infiltration and debris. Also, by having both insulation and a vapour barrier, thermal storage becomes a possibility. Therefore, heat is stored throughout the day, and later released at night, which limits the need for heating during winter. How to Insulate a Flat Roof for a Cold Roofing System A cold roof, often referred to as a vented roof, is designed as a two-part structure that enables air to circulate between the insulation layer on one side and the waterproofing layer on the other. This roofing system’s goal is to mitigate humidity buildup through effective ventilation. The one drawback with this type of ventilation is that it can lead to humidity seepage in two ways: Snow infiltration Moisture buildup inside the enclosed space The second point is especially recurrent as condensation occurs as soon as: The temperature in an area dips below the dew point The temperature outside changes suddenly To add to this, this type of roofing is expensive, which is why it isn’t commonly used. This is all the more true in Quebec, where inclement weather often contributes to mould growth with this kind of roof. Are you looking for experts for your insulation project? Fill in our form to be connected with top-rated contractors! How to Insulate a Flat Roof from the Inside or Outside Source: Canva Whether it be installed from the inside or outside, the first thing you need to ask yourself is, “Where should the insulation be installed?” In this specialized trade, three configurations should be considered, depending on where the flat roof’s waterproofing layer is positioned: Insulation beneath the waterproofing layer (cold roof) Insulation atop the waterproofing layer (inverted) Insulation around the waterproofing layer 1. Insulating under the waterproofing layer This is the most common configuration for flat roof insulation. The layers are stacked, bottom first, like so: Load-bearing structure Insulation Waterproofing There’s an alternative with timber flat roofs. With such a roofing system, the insulation is placed directly between the trusses. The insulation and structure make a single layer. This type of insulation method meant for flat roofs is especially used with cold roofing systems, which we’ll discuss further in this article. 2. Laying insulation above the waterproofing membrane Using this method, also referred to as “inverted roof insulation,” the waterproofing layer sits beneath the insulation. It thus protects the waterproofing layer from any weather-related damages. However, since the waterproofing doesn’t protect the insulation, the latter is subject to humidity and mould. Hence, an inverted roof insulation system must have the following three characteristics: Withstand diffusion Waterproof Be frost-free The only insulation material that has all three of these characteristics is extruded polystyrene (XPS). This material is sold in panel form, which is later laid on the roofing, and covered with a layer of gravel or timber. This type of flat roof is highly sought-after during renovation projects. It means the insulation-related work can be carried out without having the replace the existing insulation. This is known as a hybrid roofing insulation system. Nonetheless, it still has three major drawbacks: The weight of the panels can weaken the structure Heat loss can occur via the roof’s edges Water can seep beneath the insulation The water that seeps between insulation panel gaps will eventually reach the insulation layer. Rainfall, which is often described as cold water, will reduce the home’s thermal performance. 3. Adding insulation around the waterproofing This technique is made possible with two layers of insulation: one above the waterproofing and one beneath it. It includes the first technique mentioned, the one used for inverted flat roofs. This type of layering limits heat loss during periods of rainfall. However, the same constraints, in terms of the roofing finish that apply to inverted roofs, also apply here. Since the waterproofing membrane is laid atop the first insulation layer instead of the structure itself, thermal amplitude can increase the flat roof’s mechanical constraints. This is especially true when it comes to edges and joints. Meeting Effective Insulation Standards by Choosing the Right Material Source: Canva Since the end of 2012, Part 11 of the Quebec Construction Code and Novoclimat program have mandated a minimum R-41 rating for all flat roofs. However, this regulation solely applies to new constructions. To reach this value, you can turn to the following insulation materials: Polyurethane or urethane Glass wool (fibreglass) Polyurethane or urethane “Polyurethane” and “urethane,” are terms used interchangeably. They both refer to the same insulation material. Urethane insulation is a worthwhile insulation for flat roofs. They’re sold in either foam or panel format and are especially efficient materials for insulation, soundproofing, as well as waterproofing. Polyurethane has an R-value, per inch thick, that’s between 5 and 7. Glass wool Glass wool is one of the most commonly used insulation materials for flat roofs. Albeit fibreglass isn’t as efficient as polyurethane, it’s still a pretty decent insulation material. It has an R-value, per inch thick, that’s between 2.2 and 2.7. Glass wool is a mineral wool made with sand and recycled glass. It’s a great thermal and phonic insulation material that’s also especially resistant to humidity. It’s super easy to install and doesn’t require any sort of regular maintenance. What about EPDM (Ethylene Propylene Diene Terpolymer)? EPDM’s R-value is somewhere between 0.24 and 0.33, however, it isn’t an insulation material per se. The truth of the matter is that this elastomer assembly is actually a single-layer membrane that serves as roofing for flat roofs. As such, you won’t want to insulate your flat roof with an EPDM membrane. How thick should a flat roof insulation be? However thick the insulation layer should be truly depends on the flat roof’s structure and intended purpose. For thermal insulation, the recommended thicknesses are between 10 and 15 cm, based on the insulation type selected. Regardless, to reach the required R-41 rating, you’ll have to take into account the chosen material’s R-value. As such, given the above-listed properties, fibreglass insulation should be thicker than one made of polyurethane. Insulating Your Flat Roof: A Sustainable Investment for Unparalleled Comfort The insulation stage is crucial to improve a building’s energy efficiency while also benefiting from unparalleled comfort. By choosing the right materials, you can significantly reduce heat losses during wintertime and maintain a comfortable temperature during summertime. By investing in quality insulation, you’re also reducing your long-term energy expenses and carbon footprint. Insulating your flat roof means ensuring your indoor space is comfortable and eco-friendly.

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