Here’s How To Insulate A Garage
Your home is your own private sanctuary, a place of cozy warmth, enticing aromas, and calming interior design. Your garage, however, garners comparisons to an old-fashioned outhouse, as its cold, dark, and smelly nature has the kids believing it’s a breeding ground for spooky spirits and festering creatures. It’s time to change that.
Unfinished walls, thin metal doors, and concrete floors make the garage a chilly place to hang out, but with some ambition and a weekend DIY insulation plan, you can turn that around. Not only will your garage feel more like a part of the house, but installing insulation will save you money on energy costs and make for better storage space.
Dig in deeper below as The Drive partners up with our friends from BobVilla.com to provide all the information you need in The Drive’s guide, How To Insulate a Garage.
Benefits Of Insulating a Garage
The goal of insulation is to insulate or protect something with a heat- and sound-resistant material, the inside of the garage from the harshness of the world outside. Basically, it keeps it hot inside when it’s cold outside and cold inside when it’s hot outside. The key benefits include:
- Prevents air leakage
- Stops heat transfer
- Saves energy costs
- Temperature regulation
To insulate your garage, you need framing., Depositphotos
Types of Insulation
There isn’t just one type of insulation, despite what big box stores and their name-brand insulation would have you believe. Let’s dig in.
Blankets (Batts and Rolls)
The most common type of insulation is seen in the form of batts or rolls, which are generally called blanket insulation. The main difference is a batt is a pre-shaped and cut rectangle, while a roll of insulation comes wrapped up like a Fruit By The Foot.
Unlike blanket insulation, loose-fill has no shape, as it resembles the stuffing from inside a teddy bear. It is typically blown into spaces on top of a barrier and is great for filling odd shapes or spaces.
Sprayed or Foam-In-Place
One of the easiest methods, spray or foam insulation is literally spread over and throughout areas by shooting the insulation at the wall like a hose.
Added to the frame of the building, rigid foam insulation boards are typically used when remodeling or building a house.
As the name suggests, reflective insulation reflects heat. It helps cut down on downward heat flow.
A radiant barrier is made to keep spaces cooler, with special designs that protect against consistent intense sunlight.
What Is R-Value?
The Department of Energy states R-Value is the measurement of the ability of insulation material to reduce heat flow. The higher the R-Value, the better the insulation.
What Are The Pros and Cons of Various Types Of Insulation?
“Insulation is rated by its thermal value (R-value), and the higher the number, the greater the insulating effect.”
- “The most common type of insulation, fiberglass batts, offer R-11 to R-13 insulating value, depending on the brand, and installing them can be a DIY project. ”
- “Blown-in cellulose is popular for garage attics, and this type of insulation is also DIY-friendly. Cellulose insulation has an approximate R-value of 3.5 for each inch of insulation. For instance, a 10-inch-thick layer would add a value of R-35.”
- “Rigid foam panels can be cut to fit inside stud walls, and they come with an R-value of about 4.5 or 5 per inch. They are slightly less DIY-friendly because they can be difficult to cut precisely without leaving gaps.”
- “Spray foam insulation is dense and offers an R-value of about 6.2 per inch, but it can be tricky for a DIYer to install, and some types require a certified installer.” – Taylor
What Is The Best Insulation For a Garage?
Due to its solid R-Value, wide availability, relatively low cost, ease of installation, and relatively unmessy nature, we recommend fiberglass batts or rolls for your DIY project.
Always use gloves when installing insulation., Depositphotos
Garage Insulation Basics
Estimated Time Needed: Approximately 1-2 days, depending on how big the garage is
Skill Level: Beginner
Garage Insulation Safety
Working in your garage can be dangerous and messy, so here’s exactly what you’ll need to ensure you don’t die, get maimed, or lose a finger—hopefully.
- Safety glasses
- Fiberglass-proof mask
- Pants and a long-sleeved shirt
Everything You’ll Need To Insulate a Garage
We’re not psychic, nor are we snooping through your toolbox or garage, so here’s exactly what you’ll need to get the job done.
- Hammer tacker
- Box cutter
- Ladder or stilts
- Knee pads, if desired
- Fiberglass batts of insulation for walls
- Spray foam insulation for nooks and crannies
- Blown-in insulation for the ceiling
- Garage door insulation kit
Organizing your tools and gear so everything is easily reachable will save precious minutes waiting for your handy-dandy child or four-legged helper to bring you the sandpaper or blowtorch. (You won’t need a blowtorch for this job. Please don’t have your kid hand you a blowtorch—Ed.)
You’ll also need a flat workspace, such as a garage floor, driveway, or street parking that’s also well-ventilated. Check your local laws to make sure you’re not violating any codes when using the street because we aren’t getting your ride out of the clink.
Here’s How To Insulate A Garage
In this example, we will use fiberglass matts as the primary method of insulation. We assume the exterior walls of your garage have typical wooden stud framing and are without drywall. Let’s do this!
- Clear out the garage and remove any obstructions that could get in the way.
- Locate any small or odd spaces, measure them out, and use the box cutter to cut these specific shapes from a batt. Always use custom pieces and do not smash, squish, or shove insulation into a tough spot. The insulation needs to be flat, evenly distributed, and securely in place to work to its fullest potential.
- Fit the odd shapes into the wall like pegs into holes. The insulation should be appropriately deep to fill the entire space between the wall and the edges of the frame. Do this until only tall straight openings remain.
- Nail or staple the insulation in place, if necessary.
- Measure and cut the batts to the necessary size and shape of the wall studs.
- Pick a corner, start there, and work your way around the garage.
- Place the insulation near the floor and slowly press the insulation in, but do not smash it. Work your way up the wall.
- If there are gaps remaining, cut pieces of insulation to fill the gaps.
- Add a vapor barrier, if necessary.
Note 1: As mentioned, some insulation needs to be stapled or nailed in place. Others, however, use friction and force to hold in place. Check the insulation for instructions.
Note 2: Some garage walls might have electrical lines running through them. Do not place the insulation over the wiring or electrical lines. Instead, cut small slits into the insulation and tuck the electrical wiring inside of the insulation.
The Garage Door
- Prepare a sturdy and secure scaffolding, platform, ladder, or set of stilts. If necessary, grab a friend to hold the ladder.
- Before installing the insulation, install baffles into the eave space to ensure ventilation within the ceiling and avoid moisture damage.
- Measure, cut, and install insulation in small or odd spaces.
- Measure the stud spaces you will be filling and cut the rolls or batts to the appropriate sizing.
- Install the roll or batts into the ceiling, pushing the insulation up into the joists before pulling it back down into place for full and even coverage.
- Make sure all edges are flush and there are no gaps.
- Fill any gaps by cutting custom pieces of insulation.
- If required by code, staple the facing of the insulation into the joists to keep them in place.
Note: Keep insulation at least three to five inches away from any light sources. Insulation installed too close to a light fixture could result in a fire.
Insulation can also be blown in., Depositphotos
“The simplest way to install insulation in a typical garage attic will be to blow it in. The ceilings in most garages will already have drywall installed or plywood panels and there’s also probably an access door, in order to get to the wiring, etc. The homeowner will need to be able to get into the attic to blow in the insulation. Where he has to be careful is to step only on the joists, he can’t step between them on the underside of the drywall, or his foot will go through. He can cut some 2-foot-by-4-foot pieces of plywood to lay across the joists to step on if he likes. That’s a bit more secure.
“The other thing he has to be careful about (and this is all on the bag of insulation) is not to block intake vents in the eaves with insulation. When you blow-in insulation, it actually comes out pretty slow and drippy, so it’s not difficult to avoid the vents. Some builders like to cut a strip of batt insulation and use it to block the eave vents and then pull it out after blowing in the insulation.
“Oh, and it’s a two-person task. One person remains in the garage and loads insulation into the hopper while the other holds the end of the long flexible hose and directs the flow of insulation.” – Taylor
Do I Need a Vapor Barrier?
A vapor barrier, also known as a vapor diffusion retarder, prevents moisture buildup. Its ability to help stop the rate at which vapor can transfer through a material is measured in “perms” (permeability).
For example, glass, sheet metal, a polyethylene sheet, or a rubber membrane are Class I vapor retarders with a rating of 0.1 perms or less. Class III vapor retarders, greater than 1.0 perms but less than 10 perms, include unfaced fiberglass insulation, cellulose insulation, brick, or concrete blocks.
In general, vapor barriers are needed in areas with cold or mixed climates. Some insulation has facing already built-in, so check which type you have. Check with local building codes and consult a professional while buying your insulation to determine if it’s needed in your home and in your area. When installing, be sure to seal any openings where air could potentially leak.
“Vapor barriers are highly controversial because anything that can keep moisture from seeping into a structure can also keep it from seeping out, which can lead to mold and mildew growth. There may already be a vapor barrier (like Tyvek) between the sheathing and the siding. Some communities require a vapor barrier on the inside of the insulation in living spaces, and some don’t. They may want to check with the local building authority but it’s probably just a matter of choice since it’s a garage. Now, if they were converting it to a living space, stricter rules would apply.
“The facing on faced insulation will form a vapor barrier. Whenever you’re insulating with faced insulation, the faced side goes toward the climate-controlled part of the structure–toward the inside of the garage.”
Should I Seal My Garage Floor?
Painting a garage floor will not help with temperature regulation, but it makes it look a whole lot nicer. For more information, read The Drive’s guide, How To Paint a Garage Floor.
Pro Tips to Insulate a Garage
Our pals at BobVila.com have performed dozens of garage projects and have knowledge and experience with insulation. Here’s what they had to say:
- “Address any moisture problem before insulating since water from a leaky roof or window will damage insulation.
- “Seal all gaps around doors and windows to keep drafts out. If you take the time to insulate your garage—do it right—block the drafts while you’re at it.”
A roll of insulation can be cut to fit between the framing., Depositphotos
We’re not all reading learners. So here’s a helpful video to get you on your way.
The Drive and its partners may earn a commission if you purchase a product through one of our links. Read more.
What is the Best Insulation for a Garage?
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The time has finally come – it’s time to insulate the garage, but you’re wondering “what insulation should I use in my garage?”
Whether you’re looking to make the garage itself more comfortable, or you’re just looking to stop outside temperatures from getting into your house through the garage, insulation can definitely help.
The best insulation options for your garage will depend on whether the space has existing drywall or if the walls and ceiling are exposed. The most common insulations used in garages include fiberglass, cellulose, spray foam, and injection foam.
RetroFoam of Michigan has been in the foam insulation game since 2002. While we specialize in foam insulation, we know a lot about other insulation materials and how they work.
Now let’s get down to the nitty-gritty of garage insulation.
The Best Insulation for Garage Walls and Ceiling
There are a lot of reasons to insulate your garage.
- Your garage is attached and allows the outside air to get inside your home through the common wall.
- The bonus room above the garage can’t maintain a constant temperature and is uncomfortable.
- The smells from the garage are getting in your home.
- You want your garage to be a more comfortable space that can maintain a regular temperature.
- You want to utilize the area as a man cave or a she-shed.
- The builder didn’t finish the garage with drywall and insulation, so it’s always been on your to-do list.
There are a couple of material choices for garage wall insulation and garage ceiling insulation. Here are your options and how they are applied.
Fiberglass Garage Insulation
Fiberglass insulation can be installed in the garage as batts or rolls in the exposed wall cavities and exposed ceiling. There is also fiberglass made specifically for insulating the garage door.
Fiberglass is a common insulation found in homes and garages. The rolls and batts need to be cut to fit into the wall or ceiling cavity perfectly and stapled into place. If you don’t intend to tear down your drywall, fiberglass isn’t a good fit, as it can only be installed in the open cavities.
Fiberglass is an inexpensive option that you can install on your own, but you have to take safety precautions if you are handling the material. Small fiberglass fibers can embed in your skin and can even be inhaled.
If you are looking to stop all air movement into your garage, fiberglass isn’t the best fit as it still allows for air to move through it.
Cellulose Garage Insulation
Cellulose insulation can be blown-in into the walls and ceiling cavity of the garage.
This will only work if the walls and ceiling cavity are covered with drywall. The cellulose is blown into the cavity through holes that are drilled into the drywall and then covered, or it can be done from the outside by removing a row of siding or drilling into the mortar to blow the cellulose into the cavities.
If the walls are exposed, wet-applied cellulose is recommended, as blown-in won’t work in this application. Wet-applied cellulose is mixed with a bonding agent and sprayed into the wall cavity. If mixed properly, the wet cellulose will stick to the cavity without a netting requirement.
Cellulose is another cheap option for garage insulation. For both applications, it would be best to hire an insulation contractor as the installation process is more complicated.
Much like fiberglass, cellulose will still allow for air movement through the material.
Spray Foam and Injection Foam Garage Insulation
Spray foam and injection foam are similar, as they are foam-based products, they are just applied differently.
Spray foam insulation would be applied to the open cavities of the walls and ceiling to create an air seal. Open cell spray foam and closed cell spray foam are the two materials you can choose from.
Open cell spray foam is more pliable and is better suited if you plan to add drywall after the foam is installed. Closed cell spray foam is better if you plan to keep the walls exposed because it is very durable and can take being knocked into. The closed cell spray foam can also be used to insulate the garage door.
Injection foam is installed in the enclosed cavities by drilling holes in the drywall and injecting the foam. A good contractor will apply a rough patch over the plugged holes in the drywall. This can also be done from the outside similar to the blown-in cellulose.
One thing to keep in mind is if the garage ceiling is finished and you want to use closed cell spray foam, then the drywall will need to be taken down. If you choose open cell in the same scenario, only strips will need to be cut to apply the foam. In either case, the drywall is replaced with a rough patch of mud to cover the seams.
Foam insulation is the more expensive option and can only be installed by an insulation contractor. While foam is more expensive, it will save you money in the long run in energy savings each month.
Best Way to Insulate Garages
When it comes down to it, it’s up to you to decide what insulation material will work best for your garage.
Your expectations and what your overall goals are will help you determine the insulation that works best. If you want a conditioned space that keeps the cold air out of your home or bonus room, a material that creates an air barrier is your best bet.
Fiberglass and cellulose don’t create the kind of air barrier you’re looking for in this scenario, so foam insulation is a better option.
If you want to learn more about the benefits of an air seal and foam insulation, check out the Learning Center on our website.
How Much Does it Cost to Insulate a Garage with Foam Insulation?
Garage Insulation Problems: Things to Know Before You Insulate
Should I Insulate the Wall Between the Garage and House When Updating Exterior Wall Insulation with Foam?
How to insulate a garage from the inside: the basic rules of thermal insulation
A garage often becomes not only a parking place for a personal car, but also a room for repairs, storage of food supplies from the dacha, even the car owner’s rest. A concrete, brick or metal building protects from precipitation, but an uninsulated structure is unable to protect against winter cold or summer heat. It will be uncomfortable for a person to be in it, vegetables, fruits and preservation will quickly deteriorate, and the life of the car directly depends on the conditions of its maintenance.
Temperature regime in the garage
Garage insulation will help create a special temperature regime inside, protect against excessive cold, heat or dampness, and allow efficient use of a heater or fan if there is a person inside the room. Ideally, an insulated garage should become like a thermos, keeping the required temperature inside for as long as possible.
Even the highest quality insulation does not heat the room, but only prevents it from cooling down. Therefore, when carrying out repair work or other purposes, for a comfortable stay of a person inside the garage in winter, it will be necessary to use a fan heater or other heater.
It is important that even in severe frosts the temperature in the garage does not drop significantly below zero. A slight temperature difference inside and outside the garage will prevent the formation of condensate on the car body when leaving the premises. It is believed that in order to protect the car from rust, it is enough to ensure that the temperature inside the garage during the autumn-winter period is not lower than + 5 ° C. The car itself contributes to maintaining a positive temperature, the engine of which after driving remains warm for a long time in a well-insulated room.
Choice of materials for garage insulation
When choosing insulation for a garage, its advantages and disadvantages should be taken into account:
- Styrofoam is a cheap insulation material. It is light, its plates have different thicknesses. The material is biologically and chemically inert, easy to cut and install, and has a long service life. The disadvantage of polystyrene is its low vapor permeability, as well as instability to fire.
- Glass wool has high thermal insulation properties, prevents the formation of fungus and mold, and does not attract rodents. The disadvantages of glass wool are its high hygroscopicity, as well as the difficulties that arise during installation.
- The advantages of mineral wool include low thermal conductivity, durability, fire resistance and environmental friendliness. However, this insulation is able to accumulate moisture and lose its original shape, and hence the thermal insulation properties.
- Extruded polystyrene foam is a durable, refractory, biologically and chemically inert material with a low thermal conductivity. The disadvantage of expanded polystyrene is low vapor permeability, which can cause condensation.
- Ecowool is an eco-friendly, refractory insulation with a low thermal conductivity. The disadvantages of ecowool include the complexity of installation, shrinkage during operation.
- Polyurethane foam has high adhesion, is easily applied to any surface, forming a monolithic heat-insulating coating. PPU is fireproof, has a long service life, is quickly mounted, does not require fasteners and frame preparation. Allows you to get an energy-efficient heat-insulating layer of minimum thickness, does not create additional loads on the structure. The disadvantages of PPU include the need to use special equipment with which the insulation is sprayed.
Garage insulation technology
Ceiling and wall insulation
Garage ceiling insulation technology varies depending on the selected insulation, as well as on the roof covering material. If boards are used as the basis of roof ceilings, then the installation of such heat-insulating materials as mineral wool, polystyrene foam, glass wool, extruded polystyrene foam can be carried out without first installing the frame.
Insulation technology in this case consists of the following steps:
- installation of a waterproofing layer;
- laying a heat insulator;
- vapor barrier installation;
- exterior finish.
If reinforced concrete slabs or metal sheets are used as a ceiling, then before installing the heat-insulating layer, it is necessary to equip a special frame on which the heat-insulation will be attached. Wooden slats are used to create the frame. Insulation is placed directly between them. At the same time, the distance between the slats is made according to the size of standard insulation boards so that it fits completely.
If polyurethane foam is chosen as thermal insulation, then the insulation technology consists in spraying insulation directly onto the garage ceiling. PPU does not require the creation of a frame, the laying of vapor and waterproofing layers, and also does not need final finishing if it is not exposed to direct sunlight. Polyurethane foam coating has an aesthetic appearance. The energy efficiency of a 5 cm thick polyurethane foam insulation is comparable to a 15 or 20 cm mineral wool slab.
A freezing floor will negate the insulation of all other structural elements, so it is imperative to create an energy-efficient, wear-resistant, durable floor covering. The most common method of insulation is laying insulation under a concrete screed. Works include the following stages:
- leveling, tamping and surface cleaning;
- laying a waterproofing layer;
- installation of insulation;
- applying concrete screed;
The second way to insulate the garage floor is to create a raised floor. This method is advisable to use when it is not possible to apply the previous method. Raised floor technology includes:
- surface waterproofing;
- installation of the frame – wooden or metal logs;
- laying insulation;
- installation of a vapor barrier layer;
- exterior trim.
As a rule, garage doors are made of sheet metal with a flat surface, the installation of insulation on which does not cause problems. Mineral wool or extruded polystyrene foam is mounted directly on the door surface using special adhesives. After that, on top of the insulation, the garage doors are sheathed with chipboard, OSB, QSB, sheets of plastic or metal.
In the case of door insulation with polyurethane foam, the system is applied to the surface, forming a monolithic thermal insulation layer that does not need final finishing if the sun’s rays do not fall on it.
how and how to insulate garage walls
1. Thermal insulation or heating
2. Garage insulation requirements
3. Insulation selection
4. Internal thermal insulation
The garage protects the car from rain and wind. A good garage should also protect the car from temperature extremes. The optimum temperature for storing a car in winter is +5 ° C. Do-it-yourself insulation of the garage from the inside will help to maintain it. How to conduct it, what materials to use – we tell in this article.
Temperature fluctuations cause condensation inside the garage. Small drops of water settle on the metal parts of the machine and provoke the formation of rust. Maintaining a certain thermal regime will help to avoid this – the garage should have a positive temperature, but not too high.
For air heating up to +5 °C, the use of a heating system is usually not required. Economically, it is less profitable than thermal insulation. Moreover, from an uninsulated room, thermal energy will quickly go outside.
Another question – from which side to assemble the insulation “pie”: from the outside or from the inside? Warming the walls of the garage from the outside is preferable, as it does not eat up the interior space and shifts the dew point to the surface of the finish, thanks to which condensation does not form either inside the garage or inside the “pie”. But external thermal insulation is not always possible. An obstacle for her is the location of garages close to each other, as well as weather conditions – cold, precipitation.
When it is not possible to carry out external work, the “pie” is assembled from the inside, using an additional layer of vapor barrier, if necessary, so that condensation does not form in the room. Internal thermal insulation can be carried out at any time of the year, without coordinating your actions with your neighbors.
Thermal insulation or heating
How to properly insulate a garage from the inside? There are a few important points to consider:
- Ventilation openings must not be blocked. The room must be ventilated so that dampness and gases dangerous to humans do not accumulate in it.
- Insulation “cake” must be collected not only on the walls, but also on the floor and ceiling, so that the cold does not get through from either side.
- It is worth choosing a quality thermal insulation material. It should have a low coefficient of thermal conductivity, high moisture resistance and environmental friendliness.
Garage insulation requirements
It is possible to insulate the garage from freezing using various materials. Today on the market are rolled and plate products, spray products, special paints, plasters. Consider the most popular heaters.
This name combines three heaters that are produced in the form of rolls and plates: slag wool from blast-furnace slag melt,
All three materials have a fibrous structure, retain heat well, and soundproof the room. Cotton wool does not burn, but is afraid of water – when wet, it loses its heat-insulating properties. Glass wool also crumbles. When working with it, it is necessary to wear a protective suit, a respirator, gloves, otherwise the smallest particles of the material can cause irritation on the mucous membranes and skin.
If you plan to choose this insulation, get ready for the fact that you need to include vapor and waterproofing in the “pie”.
Lightweight gas-filled material in the form of sheets and plates. 98% air, 2% polystyrene. It has a low coefficient of thermal conductivity, does not absorb liquid, is environmentally friendly and durable. Expanded polystyrene is easy to mount on your own – it can be cut with a simple construction knife. In this case, protective equipment is not needed. Poor quality materials can be combustible and fragile. But products from reliable manufacturers meet all the requirements.
We recommend using KNAUF Therm® Styrofoam as insulation for the garage Dacha . This is an environmentally friendly and inexpensive product for protecting non-residential buildings from the cold.
Spray material with one of the lowest thermal conductivity coefficients. Thanks to the method of application, it forms a seamless layer, without cold bridges. Not afraid of moisture and rodents. An environmentally friendly product lasts up to a quarter of a century. However, this insulation cannot be attributed to cheap means, and to work with it, it is necessary to rent expensive equipment. You will also need a protective suit.
The roll material consists of polyethylene foam and a foil top layer. It is thinner than expanded polystyrene or mineral wool, its thermal conductivity is higher. Eco-friendly, durable product can be used as an additional layer in the “pie”. Foil reflects infrared radiation coming from inside the room, therefore this type of material is appropriate to use only in heated spaces.
Like reflective insulation, these medium conductive products can be added layers to the pie. Insulating paint is a polymer-based composite consisting of hollow ceramic microspheres. The composition of warm plaster, in addition to the binder, gypsum or cement, includes porous materials – quartz sand, vermiculite or polystyrene foam.
Paint and plaster
KNAUF THERM® PRODUCTS FOR GARAGE INSULATION
KNAUF THERM® COTTAGE
Internal thermal insulation
As we mentioned above, the “pie” inside the garage must be assembled on all surfaces – walls, ceiling, floor, gate. In this case, the floor “pie” will be different from the rest. Consider how to assemble it using polystyrene foam.
The best way to protect it from freezing is with a screed. So that the floor level does not rise and does not prevent the car from entering the garage, you should dig a small pit – its depth should be equal to the thickness of the heat-insulating “pie”. The soil at the bottom of the pit is carefully compacted. Then the concrete screed is poured. When it dries, waterproofing sheets are laid, roofing material will do. Sheets must be overlapped. Insulation is mounted on top, for example, durable Knauf Therm® polystyrene foam Floor. Its fragments should be tightly adjacent to each other. The insulation is covered with another layer of waterproofing material. Make the final reinforced screed. The final stage is the installation of the finished floor.
How and how to insulate garage walls from the inside? The easiest way is to assemble the “pie” again using Styrofoam. At the beginning of the process, the walls are cleaned of old paint, dust, dirt, cracks are filled with cement mortar, primed for better adhesion. At the second stage, a starting profile is attached to the bottom of the wall, from which polystyrene foam sheets begin to be glued onto a special composition. It is important that there are no gaps between them. If gaps remain, they should be filled with foam.
From above, expanded polystyrene can be covered with a vapor barrier film, by mounting its sheets with an overlap and gluing the joints with construction tape. From above, the structure is closed with siding or other trim. An alternative option is to plaster a layer of insulation.
“Pie” with mineral wool with insulation of a metal garage will look different. You can also watch a video on how to mount polystyrene foam.
Garage ceiling insulation and garage roof insulation we have dedicated separate materials. Here we note that the principle of operation is similar to the technology of wall insulation. It is necessary to collect the “pie”. With polystyrene foam, it will be simple: a primed ceiling, a layer of insulation, reinforced plaster. For the installation of mineral wool, you will need to assemble a crate from a bar impregnated with fire retardants and anti-rotting compounds.