Quick Answer: An insulated shipping container with 4 inches of closed-cell spray foam (about R-24, the walk-in-cooler value referenced by NRC Codes Canada) and a 1 to 2-ton split system holds 0 to 15 °C reliably for produce, brewery cellaring, mushroom grow rooms, dry-aging chambers, or food-bank cold storage. It runs at roughly a tenth of a reefer’s power draw and costs far less to operate. 30+ years operating, 4.9 stars on 140+ Google reviews. 1-3 day delivery Ontario-wide from our Brantford yards.
In This Guide
- What Is the Difference Between an Insulated Container and a True Reefer?
- When Does an Insulated Retrofit Make More Sense Than a Reefer?
- Which Insulation Method Is Best: Spray Foam, Rigid Board, or SIP Panels?
- Why Do Cold-Storage Containers Get Condensation, and How Do You Stop It?
- How Do You Insulate the Floor and Reseal the Doors?
- What Size Refrigeration Unit Does an Insulated Container Need?
- How Do You Monitor Temperature and Humidity in a Container Cooler?
- What Can You Use an Insulated Cold-Storage Container For in Ontario?
- What Does It Cost to Build an Insulated Cold-Storage Container?
- Paul’s Take on the Middle-Ground Build
- FAQs
Reading Time: 17 minutes
What Is the Difference Between an Insulated Container and a True Reefer?
An insulated shipping container is a dry-grade steel box lined with closed-cell spray foam, rigid board, or SIP panels and paired with a small split-system cooler, holding the 0 to 15 °C range. A true reefer is a factory unit with a built-in 10 to 15 kW refrigeration plant reaching minus 25 °C. The shell insulates; the reefer refrigerates.
Buyers call our Brantford yard every week asking for a “cold container,” and the first thing we work out together on the phone is which kind they actually need. There are two distinct products under that umbrella, and confusing them can push a buyer toward thousands of dollars of unnecessary spend on the wrong unit.
A refrigerated container, often called a reefer, is a factory-built unit. The steel walls hide 75 to 100 mm of polyurethane foam pre-bonded inside a stainless-steel skin. A 10 to 15 kW refrigeration unit sits at one end and can pull the interior down to minus 25 °C and hold it there in a Sudbury winter or a Niagara August. It is the right tool when you are freezing fish, holding pharmaceuticals at 2 to 8 °C, or stockpiling ice cream. We sell 20 ft and 40 ft HC reefers and we ship them with the Carrier or Thermo King units serviceable.
An insulated container is a different animal. It is a dry-grade shipping container, usually a one-trip 20 ft or 40 ft (if you are looking at a used shell instead, our walkthrough on grading a unit before you pay covers what to check), that we (or your contractor) line on-site with closed-cell spray foam, rigid board, or a SIP system. There is no factory refrigeration unit. A cold room is one branch of the wider family of container build-outs we cover; to bring this one down to a working temperature, you pair the insulated shell with a residential or light-commercial split system, often controlled by an aftermarket controller that lets a standard AC run below its normal cut-off point.
The shell holds temperature; the small split unit removes the heat. Together they sit in the 0 to 15 °C range that covers most produce, beverage, and grow-room work. Below freezing or for medical-grade precision, this build is not the right answer. Above freezing, it is often the smarter spend.
The Industry Distinction in One Paragraph
Industry classifies thermal containers in two families. Reefer containers (ISO 1496-2 specifies the testing standard for thermal containers) carry a factory cooling unit and a CSC plate that confirms structural compliance for ocean shipping. Insulated containers carry insulation but no built-in refrigeration; they slow heat transfer rather than actively removing it. A reefer can be unplugged and used as a passive insulated container in a pinch, but a reefer that has lost its refrigeration unit (or is being sold as a “non-running” reefer) is essentially an insulated container with extra weight and a non-functional condenser hanging off the end. Buyers should know which they are buying before they pay.
When Does an Insulated Retrofit Make More Sense Than a Reefer?
If your operating range is 0 to 15 °C, an insulated container with a split system beats a reefer on three measurable axes.
Christian LeBlanc, second-generation operator: “Most callers ask for a reefer because that is the only cold container they know exists. We grab a dry one-trip box off the yard, foam it, hang a small split system, and they are holding 4 °C for a fraction of the reefer hydro. I grew up around this trade, traveling to Asia with my dad from the time I was 15, and the pattern never changes: the buyer who tells us the temperature they actually need walks away with the right build the first time.”
Power draw. A 20 ft reefer running at 4 °C will pull 4 to 6 kW continuously in the Ontario summer. A 1-ton (12,000 BTU) mini-split holding the same 4 °C inside a properly insulated container draws 1 to 1.5 kW. Over a year of operation, that gap is the difference between a hefty reefer hydro bill and a small fraction of it at southern Ontario commercial rates. Brewery clients see the gap show up on the second monthly statement.
Capital cost. A 20 ft used reefer in Cargo Worthy grade carries a meaningfully higher price tag depending on the refrigeration unit’s age and service history. A clean single-voyage dry box plus a quality spray-foam job plus a 1-ton split system plus a controller comes in well under that fully built. The insulated build is significantly cheaper at the gate.
Serviceability. A reefer’s refrigeration unit is a proprietary marine-grade compressor that takes a Thermo King or Carrier dealer to service. A residential split system can be serviced by any HVAC tech in any Ontario town that has a Home Depot. When your cooler quits at 6 a.m. on a Saturday in July, the call to a local HVAC contractor goes faster than the call to a refrigeration specialist.
There are real cases where the reefer still wins. Below 0 °C, you need a reefer. Pharmaceutical or vaccine storage requiring 2 to 8 °C with audit logs needs the reefer’s calibrated unit. Heavy door-cycle traffic (a working butcher shop with the door opening every two minutes) overwhelms a small split system. And any cold storage that ships internationally needs the CSC plate that a reefer carries.
If none of those apply and your range is somewhere between a root-cellar 4 °C and a beer-cellar 12 °C, the insulated retrofit is the build that fits the job.
The Honest Test
Write down the lowest temperature you actually need to hold. If the answer is above freezing, an insulated container with a split system will do the job. If the answer is below freezing, even occasionally, buy a reefer. The cost of building an insulated unit and then discovering you needed a reefer six months in is higher than just buying the reefer up front. We have had this exact conversation enough times that we built a decision sheet around it.
Which Insulation Method Is Best: Spray Foam, Rigid Board, or SIP Panels?
Three methods dominate Ontario container cold-storage builds. Each has a place; the right one depends on budget, build quality target, and whether the container needs to stay structurally portable.
4-Inch Closed-Cell Spray Foam (The Standard)
Closed-cell spray polyurethane foam at 4 inches of depth gives roughly R-24 to R-25, which is the recommended R-value for a walk-in cooler running at 4 °C in southern Ontario. The foam expands into every corrugation of the container wall, eliminating air gaps and bonding directly to the steel. That direct bond is the reason spray foam doubles as the vapour barrier. There is no air space between the foam and the steel for warm humid air to reach the cold steel and condense.
Closed-cell foam is rigid once cured, which adds structural stiffness to the container. It is also rodent-resistant and does not absorb water if a leak develops above it. The disadvantages are honest ones: it is the most expensive method, professional installation is required (DIY foam kits are sold but rarely produce uniform depth), and the foam off-gasses for the first 24 to 48 hours after install so the container needs to ventilate before you bring food in.
Professionally spraying a 40 ft costs more than a 20 ft, and it is the priciest of the three insulation methods. Add 30 to 40 percent if you spray the ceiling and floor (which we recommend for cold-storage builds; partial-coverage foam is for residential conversions, not cold rooms).
Rigid Foam Board (The Budget Build)
Two-inch or three-inch sheets of polyisocyanurate (polyiso) or extruded polystyrene (XPS) board, friction-fit between wood furring strips and sealed at the seams with foam tape and canned spray foam, produce R-12 to R-18 depending on board thickness. The build is DIY-friendly and is the most affordable of the three methods in materials for a 20 ft container.
The honest weakness of rigid board in a cold-storage application is the seam problem. Every joint between two boards, and every junction between board and corner post, has to be sealed properly or it becomes a condensation path. A board build that looks beautiful when you finish it will run fine for one summer; the second summer, if the seams were not sealed correctly, you find black mould behind the boards and a steady drip on the floor. Rigid board works for cold storage if you are meticulous about seams and you accept that you may need to redo it in five to seven years.
For a contractor’s seasonal materials shelter or a hobby orchard packing house running August to October, rigid board is the rational spend. For a year-round commercial brewery cellar, spend the extra on spray foam.
SIP Panels (The High-End External Build)
Structural Insulated Panels, applied to the exterior of the container rather than the interior, give R-28 to R-40 depending on panel thickness and preserve every cubic foot of the container’s interior volume. The container’s 8 ft of exterior width grows to roughly 9 ft 6 in once the panels are clad in steel or fibre-cement siding, but the interior stays the full 8 ft.
SIP is the build of choice when the container is becoming part of a permanent building (a winery or apple-storage facility being inspected by Canadian Food Inspection Agency) or when interior space is at a premium (an urban brewery in a tight building footprint). It is also the most expensive method, and larger multi-container builds cost considerably more.
| Method | R-Value (4″) | 20 ft Cost | Interior Loss | Build Difficulty |
|---|---|---|---|---|
| Closed-Cell Spray Foam | R-24 | Highest | 4-5 inches per wall | Pro install required |
| Rigid Foam Board | R-12 to R-18 | Lowest | 3-4 inches per wall plus furring | DIY-capable |
| SIP Panels (exterior) | R-28 to R-40 | Premium | Zero interior loss | Pro install required |
Why Do Cold-Storage Containers Get Condensation, and How Do You Stop It?
The reason cold-storage container builds fail is almost never the insulation R-value. It is the vapour barrier and the condensation path.
Steel is a vapour-impermeable surface. When you cool the inside of a steel box to 4 °C and the outside is sitting at 25 °C and 70 percent humidity (a normal Brantford July), the steel walls become a condensing surface for any humid air that can reach them. If you put insulation against the steel with an air gap behind the insulation, you have built a condensation factory. The first year it shows up as drips on the floor. The second year you find rust pinholes and black mould.
The fix is to put a continuous, sealed insulation layer in direct contact with the steel, with no air gap and no permeable layer between the warm interior air and the cold steel surface.
Closed-cell spray foam does this in one step because the cured foam is itself a Class II vapour retarder (perm rating under 1.0 at 4 inches). The foam touches the steel, fills every void, and the warm interior humid air cannot reach the cold steel surface.
Rigid board does not do this in one step. The board itself is somewhat vapour-permeable, the seams between boards are permeable until sealed, and the air gap between the board and the steel (which exists because the board does not perfectly match the corrugation of the container wall) is a path to the steel. A board build needs an additional vapour barrier: a continuous 6-mil polyethylene sheet sealed at every joint and penetration, installed on the warm side (the interior side) of the insulation. The polyethylene stops humid interior air before it reaches the board, the board stops conducted heat, and the foam tape between boards seals the seam.
Both builds need to handle floor moisture too. The container’s marine plywood floor is the most under-insulated surface on a stock unit. We recommend a layer of 2-inch XPS board over the original floor, then 3/4-inch plywood over that, fastened to the side rails. For spray foam builds, sprayed foam over the floor before the topping is the cleaner solution.
Why Ontario’s Humidity Matters More Than the Cold
A lot of online container-conversion content is written for arid Arizona or Colorado climates where humidity sits at 20 to 40 percent. Ontario regularly hits 80 to 95 percent humidity from late June to early September across the Grand River valley, Niagara, the Lake Erie shoreline, and the cottage country lakes. That is when a poorly built cold-storage container will start dripping water from every cold spot. Whatever insulation method you choose, the vapour-barrier discipline matters more in Ontario than it does in most of the marketing copy you will read.
How Do You Insulate the Floor and Reseal the Doors?
Two finishing details separate a serious cold-storage build from a hobby build: the floor and the doors.
Floor Insulation
A standard shipping container floor is 28 mm of tropical marine plywood bonded to steel cross-members. It is engineered to carry a 30-tonne payload across an ocean. It is not engineered to keep a 4 °C interior separated from a 0 °C ground surface in February. Untreated, the floor becomes the largest thermal bridge in the cooler and the coldest spot in the box.
Two practical approaches work. The first is to lay 2-inch XPS board directly over the original plywood, then top it with 3/4-inch tongue-and-groove plywood or food-grade aluminium tread plate, screwed into the container’s side rails. This sandwich adds R-10 underfoot and lifts the working floor by 2.5 inches. The second is to spray foam directly to the original floor at 4 inches, then top it with the same tread plate or food-grade plywood. The sprayed version is more durable and waterproof; the board version is easier to repair later if a floor section gets damaged.
Door Gasket Replacement
The original cargo doors on a shipping container seal against weather, not against cold air loss. The four cam-lock bars compress two rubber gaskets that are designed to keep ocean spray out. They are not designed to hold a 20-degree temperature differential between interior and exterior for a year.
For a cold-storage build, two paths exist. The cheap path is to replace the original gaskets with thicker, softer EPDM rubber and adjust the cam-lock keeper plates so the gaskets compress under load. This works for a 0 to 15 °C build and is an inexpensive parts upgrade.
The serious path is to install a proper insulated walk-in cooler door from a refrigeration supply house, cut into the side of the container, with the original cargo doors either welded shut or kept as a secondary opening. A walk-in cooler door has a sweep gasket on the bottom that drags across the floor as it closes, a magnetic gasket on the strike side, and a foam-cored door panel that matches the wall R-value. It costs significantly more installed and is the right answer for any operation that opens the door more than five times a day.
Mushroom Grow Room: Door Cycle Reality
An oyster-mushroom grower in Norfolk County opens his fruiting-chamber door 30 to 50 times a day to mist, check pinning, and harvest. He spent the extra on a proper walk-in door with a sweep gasket. Two years in, his electricity bill is roughly 20 percent of what his neighbour pays running a reefer with cargo doors. The door upgrade paid for itself in the first nine months.
What Size Refrigeration Unit Does an Insulated Container Need?
An insulated container without active cooling will hold temperature for 24 to 48 hours if you load it with pre-chilled goods, but it will not pull a load down. For continuous cold storage, you need a small refrigeration unit matched to the volume and the door-cycle frequency.
For a 20 ft insulated container (approximately 33 cubic metres), a 1-ton (12,000 BTU) ductless mini-split is the standard choice. For a 40 ft (approximately 67 cubic metres), step up to a 1.5-ton (18,000 BTU) or pair two 1-ton units if you want zoned control or redundancy. For a 40 ft HC, 2-ton (24,000 BTU) is the conservative spec.
The catch with a standard mini-split is that residential AC controllers cut out at 16 to 18 °C interior temperature to protect the evaporator coil from freezing. For a cold-storage build you need the unit to keep running down to 1 or 2 °C above your set point. Two paths solve this.
The CoolBot Controller (DIY Path)
The CoolBot, made by Store It Cold, is a small after-market controller that intercepts the air-conditioner’s temperature sensor and tricks it into running below its factory cut-off point. It uses a heating element and a micro-controller to keep the evaporator coil from freezing while letting the AC pull the room down to 1 °C. The CoolBot Gen 7 is an inexpensive controller landed in Ontario and works with most window or mini-split units rated 12,000 BTU or larger.
This is the path of choice for orchard packing houses, small breweries, mushroom growers, and food banks. The total electrical bill for the cooler running at 4 °C in a properly insulated 20 ft container with a CoolBot-driven 1-ton mini-split stays low at southern Ontario rates.
Marine-Grade Cooling Coil (Commercial Path)
For a commercial build that needs precise temperature control, a remote condensing unit with a low-temperature evaporator coil hung inside the container is the cleaner solution. This is what a refrigeration contractor builds for a winery cold room or a commercial flower cooler. It is considerably more expensive fully installed but it is designed from the ground up for the cold-storage duty cycle and will run quieter and longer than a CoolBot-modified residential unit.
Heat Pump or AC?
Cold-climate heat pumps are now common in Ontario because they cool in summer and heat in winter. For a cold-storage container, you only need the cooling function. A standard mini-split is sufficient and costs noticeably less than a cold-climate heat pump of the same capacity. If your container will double as a workshop in winter (some clients do this) the heat pump is worth the upcharge. If it is dedicated cold storage, skip it.
How Do You Monitor Temperature and Humidity in a Container Cooler?
A walk-in cooler that holds 4 °C for a year does so because someone is watching it. A few hundred dollars in monitoring equipment is the cheapest insurance you will buy on the whole build.
At minimum, install a wireless temperature logger with cellular or Wi-Fi notification. Brands like SensorPush, La Crosse, and Govee make affordable units that text or email you the moment temperature climbs above your set range. For food storage, log the temperature continuously so you have a record if a CFIA inspector asks. For a brewery cellar, log temperature and humidity together; lager fermentation cares about both.
For commercial-grade compliance (food-bank cold storage handling donated dairy, a winery storing finished product, a meat dry-aging chamber under inspection), step up to a calibrated NIST-traceable logger like the MadgeTech or Onset HOBO units. These cost more and produce audit-ready reports.
Humidity matters more than buyers expect. Apples want 90 to 95 percent humidity to avoid shrivelling. Dry-aged beef wants 70 to 80 percent. Mushrooms want 80 to 95 percent during fruiting. A small humidifier (an inexpensive ultrasonic foam-pad unit) added to the cold-storage container brings humidity up to spec. A small dehumidifier may be needed for a brewery beer cellar that wants drier conditions.
What Can You Use an Insulated Cold-Storage Container For in Ontario?
The insulated cold-storage container has found a comfortable home in five operational niches across Ontario. Each builds the same basic shell but tunes the temperature, humidity, and door configuration to the use.
Orchard Packing House Cooler (Norfolk, Niagara, Northumberland)
An apple grower running 5 to 50 acres needs to hold harvested fruit at 0 to 4 °C and 90 to 95 percent humidity from late August through November. Apples respire, give off ethylene, and lose firmness fast at room temperature. A 40 ft insulated container with 4 inches of spray foam, a 1.5-ton mini-split with a CoolBot, and a small ultrasonic humidifier holds 16 to 20 bins of Honeycrisp or Empire through the packing-and-shipping window. The whole build (container + insulation + refrigeration) comes in at a fraction of the cost of an equivalent reefer. The unit sits on the orchard pad through harvest, then runs empty November to August or stores empty bins.
Brewery Fermentation Cellar (every Ontario town with a craft brewery)
Lager fermentation wants 8 to 12 °C for two to six weeks. Ale conditioning wants 4 to 8 °C for one to three weeks. Most craft breweries cannot afford to build a refrigerated room as part of the brewhouse footprint, but they can park a 20 ft or 40 ft insulated container against the exterior wall, cut a doorway through, and pick up 600 to 1,200 cubic feet of conditioning space for a fraction of a built-out refrigerated room. The split system runs cheaply at 8 °C interior. We have shipped containers to breweries in Cambridge, Guelph, Welland, Niagara, and the Brantford area for exactly this build.
Mushroom Grow Room (Norfolk, Haldimand, Wellington)
Gourmet mushroom growers (oyster, shiitake, lion’s mane) need a fruiting chamber at 13 to 18 °C with 80 to 95 percent humidity and steady fresh-air exchange. An insulated 20 ft container with 4 inches of foam, a 1-ton mini-split running on a CoolBot, a humidifier, and a 6-inch HEPA-filtered fresh-air fan handles a 20 to 40 lb-per-day production operation. The container’s metal walls clean down easily with a pressure washer between cycles, which matters because gourmet mushrooms are vulnerable to mould contamination. Several Norfolk and Wellington growers have built this exact rig and supply farmers’ markets and restaurants from a container parked behind the house.
Food Bank and Community Cold Storage
Ontario food banks regularly receive donated dairy, produce, and prepared food that needs cold storage between donor pickup and recipient distribution. A 20 ft insulated container sited next to the food-bank building, holding 2 to 4 °C with a calibrated logger, doubles dairy and produce intake capacity without the capital cost of building a refrigerated room. The build is priced by size and spec, contact us for a current quote, and gets funded through capital grants or community foundation gifts. We have delivered to food banks in Brantford, Cambridge, Stratford, and along Highway 401.
Dry-Aging Meat Chamber (butchers, farmers, restaurants)
Dry-aging beef requires 1 to 3 °C, 75 to 85 percent humidity, gentle air circulation, and four to twelve weeks of patience. A small butcher or farm-to-restaurant operation cannot justify an expensive commercial dry-aging cabinet. A 20 ft insulated container with 4-inch foam, a 1-ton mini-split on a CoolBot, a UV-C sterilising lamp, and a small humidifier handles 50 to 200 cuts at a time for far less all-in. The container becomes a serious revenue centre for a farm operation selling direct-to-consumer or supplying restaurants.
Contractor Materials Shelter (Hamilton, Brampton, GTA fringe)
Some materials a general contractor stocks for winter work cannot freeze: latex paint, certain caulkings, mortar additives, drywall compound. An insulated container at 5 to 10 °C on a jobsite (or a contractor’s yard) keeps these materials usable through January and February. This build uses the cheapest insulation method (2-inch rigid board) and the smallest split system (a 9,000 BTU residential mini-split or even a small electric heater set on a thermostat). Total cost is modest, contact us for a current quote, and the container also stores tools the rest of the year.
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What Does It Cost to Build an Insulated Cold-Storage Container?
Ballpark for a complete insulated cold-storage container, delivered to your Ontario site, ready to run at 4 °C:
| Component | 20 ft Build | 40 ft Build |
|---|---|---|
| One-trip container (Van Blanc) | Quote | Quote |
| 4″ closed-cell spray foam (walls, ceiling) | Higher for 40 ft | Higher for 40 ft |
| Floor insulation (2″ XPS + plywood top) | Higher for 40 ft | Higher for 40 ft |
| Door gasket upgrade or walk-in door | Gasket low, walk-in door more | Gasket low, walk-in door more |
| 1-ton or 1.5-ton mini-split (installed) | Higher for 40 ft | Higher for 40 ft |
| CoolBot or equivalent controller | Low | Low |
| Temperature/humidity monitoring | Low | Low |
| Delivery (1-3 days from Brantford) | varies by zone | varies by zone |
| Total installed | Contact us for a quote | Contact us for a quote |
Compare to a 20 ft used reefer in Cargo Worthy grade, which costs considerably more (the unit itself, before delivery and any electrical work to bring 3-phase power to the site, which a reefer typically needs). The insulated build is roughly half the capital and a fraction of the running cost.
The honest exception is that the insulated build requires building work: spray foam, electrical, door cutting. If you do not have a contractor lined up or you want to be running cold storage by next Tuesday, a turnkey used reefer is faster. The trade-off is real.
Where to Get the Build Done in Southern Ontario
Spray-foam crews in Brantford, Cambridge, Hamilton, Kitchener, and the Niagara region handle container insulation regularly. KOOLJET Refrigeration in Tillsonburg specialises in container cooling systems and has built dozens of Ontario walk-in cooler conversions. Most local HVAC contractors will install the mini-split half of the build, and we keep a short list of installers at the yard for buyers who ask. The container itself ships from our 4 Brantford yards in 1-3 days. Every quote comes with a real lead time, not a hopeful one.
Paul’s Take on the Middle-Ground Build
Paul LeBlanc, owner: “Buyers come in convinced they need a reefer because that is the only kind of cold container they have heard of. Then we work out what they actually want to do, and half the time the answer is 0 to 15 °C. For that range, an insulated retrofit with a small split system is the smarter spend. The capital outlay is roughly half a turnkey reefer, and the hydro bill is a fraction of it year after year. The reefer is the right tool when you are going below freezing or you need audit-grade precision. Between those two cases, the insulated container is the middle-ground build that fits the job. I have been selling containers for 19 years, and the buyers who stop and think before they buy are the buyers who get the right unit the first time.”
This is why we sell both. A buyer who needs a reefer should get a reefer, and we have 20 ft and 40 ft HC reefers on the yard. A buyer who needs an insulated retrofit should get a one-trip dry container, the insulation contractor’s number, and a split-system installer. We can walk you through which build fits your range before you commit. The walk happens at our Brantford yard at 90 Morton Avenue East, where you can stand inside a stock dry container and a stock reefer back-to-back and feel the difference.
The brewery client who came down from Cambridge last spring had been quoted a steep figure for a turnkey reefer setup by a national supplier. He left with a one-trip 40 ft container, a contractor referral, and a build that came in for far less finished. He is fermenting at 10 °C all year and his power bill is modest each month. He texted us at Christmas to send a picture of the cellar with the lights on. That is the build we are talking about.
Frequently Asked Questions
Can you turn a regular shipping container into a walk-in cooler?
Yes. With 4 inches of closed-cell spray foam (R-24), proper vapour-barrier discipline, a 1-ton mini-split air conditioner, and a CoolBot controller (or equivalent), a one-trip 20 ft container becomes a working walk-in cooler holding 1 to 15 °C reliably year-round. The build is roughly half the cost of a turnkey reefer for a 20 ft, contact us for a current quote.
What is the difference between an insulated container and a reefer?
An insulated container has insulation but no built-in refrigeration. A reefer container has factory insulation plus a 10 to 15 kW refrigeration unit at one end. Insulated containers paired with a small split system work well at 0 to 15 °C. Reefers are the right answer for sub-zero work, precise audit-grade temperatures, or heavy door-cycle traffic.
What R-value do I need for a shipping container cooler in Ontario?
R-24 to R-25 is the industry standard for walk-in coolers operating at 0 to 8 °C in southern Ontario. Four inches of closed-cell spray foam delivers this in one step. Rigid foam board needs 4 to 5 inches plus careful seam sealing to reach the same level. Below R-20, the cooler runs but the refrigeration unit cycles harder and hydro costs climb.
How much power does an insulated container cooler draw versus a reefer?
A 20 ft insulated container cooler with a 1-ton mini-split running at 4 °C draws 1 to 1.5 kW continuously. A 20 ft reefer at the same temperature draws 4 to 6 kW. Annual hydro cost in southern Ontario is far lower for the insulated build than for the reefer.
Will an insulated container hold temperature without active cooling?
Loaded with pre-chilled goods and sealed, a properly insulated container will hold temperature within 2 to 4 °C of the starting point for 24 to 48 hours depending on outside conditions. It is not designed for continuous storage without active cooling, but it makes a good failover during a brief power outage or for short-distance transport of pre-cooled product.
Can a CoolBot really make a regular air conditioner work as a cooler?
Yes. The CoolBot Gen 7 is an aftermarket controller that intercepts a standard AC’s temperature sensor and uses a small heater plus a micro-controller to keep the evaporator coil from freezing while running down to 1 °C interior temperature. It works with most 12,000 BTU or larger window and mini-split units. Tens of thousands of small farms and breweries across North America use this exact setup.
Do I need a vapour barrier inside the container?
If you use closed-cell spray foam, the cured foam itself is a Class II vapour retarder and no additional barrier is needed. If you use rigid foam board or any other layered insulation, you need a continuous 6-mil polyethylene vapour barrier on the warm (interior) side of the insulation, sealed at every seam and penetration. Without it, condensation will form behind the insulation and rust the container from the inside out.
How long will a properly built insulated container cooler last?
The container shell, in Wind & Watertight or one-trip grade, will last 25 years or more sitting on a properly drained pad. Closed-cell spray foam holds its R-value for 20 to 30 years. A residential mini-split air conditioner has a service life of 10 to 15 years before the compressor needs replacement. Plan for one HVAC replacement in the cooler’s first 20 years.
Sources
- International Organization for Standardization. (2013). ISO 1496-2:2018 Series 1 freight containers, Specification and testing, Part 2: Thermal containers. iso.org/standard/72050.html
- Cornell Cooperative Extension. (2024). Cold Storage Chart and Reference Guide for Produce. rvpadmin.cce.cornell.edu
- Government of Canada, Health Canada. (2025). Safe food storage. canada.ca
- Store It Cold LLC. (2026). CoolBot Walk-In Cooler Controller: Product Specifications and Temperature Range. storeitcold.com
- KOOLJET Refrigeration Systems, Tillsonburg, Ontario. Container Cooling Systems for Walk-In Cooler Conversion. kooljet.com
Reach Van Blanc in Brantford
We have been supplying shipping containers across Ontario since 1995. Our warehouse is at 90 Morton Avenue E in Brantford, and we deliver right across the province with fast 1-3 day delivery from our 4 Brantford yards. Every quote comes with a real lead time, not a hopeful one.
Van Blanc Ent. Inc., 90 Morton Ave E Unit 1B, Brantford, ON N3R 7J7, +1 888-509-6658
If you are weighing an insulated retrofit against a reefer, call the yard at 519-754-6844 and we will walk you through which build fits your operating range. Worth the drive to stand inside both before you commit.