Brad, Owner since 1987: "We have been helping Brantford families sleep better since 1987. Every customer gets personal attention, honest advice, and the kind of follow-up service you just do not get from big box stores."
- Why You Sleep Hot: The Science of Thermoregulation
- How Your Mattress Traps or Releases Heat
- Cooling Technologies: What Works and What Does Not
- Mattress Types Ranked by Cooling Performance
- The Canadian Factor: Seasonal Temperature Challenges
- Night Sweats, Menopause, and Medical Hot Sleeping
- Beyond the Mattress: Complete Cool Sleep System
- Our Brantford Showroom Recommendations
- Frequently Asked Questions
Reading time: 11 minutes
Sleeping hot is one of the most common and most frustrating sleep complaints in Canada. Research suggests that approximately 41% of adults experience regular overheating during sleep, and the problem is not limited to summer months. Canadian homes with forced-air heating can create stuffy, dry sleeping environments in winter that are just as disruptive as warm summer nights. The result is the same regardless of season: fragmented sleep, frequent awakenings, restless tossing, and mornings that feel like you barely slept at all.
The mattress is often the primary culprit. Traditional memory foam mattresses, which dominate the bed-in-a-box market, are essentially thermal insulators that trap body heat against the sleep surface. But the solution is not simply to avoid memory foam. It is to understand how heat moves through a mattress, what materials and constructions promote cooling, and which cooling claims are backed by evidence rather than marketing.
Why You Sleep Hot: The Science of Thermoregulation
Your body is designed to cool down before and during sleep. This temperature drop is not incidental; it is a critical trigger for sleep onset and a requirement for maintaining deep, restorative sleep stages. Approximately two hours before your habitual bedtime, your core body temperature begins to decline, driven by vasodilation (widening of blood vessels) in the hands and feet that radiates heat away from your core. This temperature drop signals the brain to release melatonin, the hormone that initiates sleep.
During sleep, your core temperature drops by approximately 1-2 degrees Fahrenheit, reaching its lowest point (the nadir) in the early morning hours. Deep sleep (slow-wave sleep) and REM sleep are both temperature-sensitive stages that require a cool core temperature to sustain. Research by Haskell et al. (1981), published in Electroencephalography and Clinical Neurophysiology, demonstrated that environmental temperatures above 24 degrees Celsius significantly reduce both deep sleep and REM sleep duration, leading to lighter, more fragmented sleep.
Okamoto-Mizuno and Mizuno (2012), in their review published in the Journal of Physiological Anthropology, established that the optimal ambient temperature for sleep quality is 15.6-19.4 degrees Celsius (60-67 degrees Fahrenheit). The Sleep Foundation recommends a slightly more specific target of 18.3 degrees Celsius (65 degrees Fahrenheit). Within this range, the body can shed heat efficiently without becoming cold enough to cause shivering or vasoconstriction, both of which also disrupt sleep.
When your mattress traps heat, it creates a microclimate between your body and the sleep surface that can be significantly warmer than the room temperature. Even in a perfectly cooled 18-degree bedroom, a heat-trapping mattress can raise the skin-to-mattress interface temperature above 35.5 degrees Celsius, which research associates with increased sleep disturbances and decreased deep sleep time. This is why changing your thermostat alone often fails to solve the problem; the mattress itself must be part of the solution.
How Your Mattress Traps or Releases Heat
Heat moves through a mattress via three mechanisms: conduction (direct transfer through solid materials), convection (transfer through moving air), and radiation (emission from warm surfaces). The mattress's ability to manage heat depends on how well it facilitates these mechanisms.
Conduction: When your body contacts the mattress surface, heat transfers directly from your skin into the mattress material. Dense, closed-cell foams (like traditional memory foam) absorb heat slowly and release it slowly, creating a thermal reservoir that stays warm throughout the night. Open-cell foams, gel-infused foams, and latex have more porous structures that conduct and dissipate heat more efficiently.
Convection: This is the most important cooling mechanism in a mattress. Convection requires airflow, and airflow requires open space within the mattress structure. Pocketed coil systems create a significant air channel between the comfort layers and the bed base, allowing warm air to flow out and cool air to circulate in. All-foam mattresses have no such air channel, which is the primary reason they sleep warmer than hybrid or innerspring mattresses.
Radiation: Your body radiates infrared heat in all directions. The mattress surface absorbs some of this radiated heat and re-emits it. Phase-change materials (PCMs) are specifically designed to interrupt this cycle by absorbing radiated heat as they change from solid to liquid at a specific temperature threshold, providing temporary cooling during the transition.
Cooling Technologies: What Works and What Does Not
The mattress industry markets dozens of cooling technologies, but they vary enormously in effectiveness. Here is an evidence-based assessment of the most common approaches.
Effectiveness: Moderate
Gel beads or a gel matrix are mixed into the memory foam during manufacturing. The gel absorbs body heat and distributes it across a larger surface area, reducing localized hot spots. Research indicates gel-infused foam provides noticeably cooler initial contact (the first 1-2 hours of sleep) compared to traditional memory foam. However, once the gel reaches thermal equilibrium with the surrounding foam, its cooling advantage diminishes. Gel foam is better than traditional memory foam but is not a complete solution for significant hot sleeping.
Effectiveness: Moderate to Good
Open-cell foam replaces the closed-cell structure of traditional memory foam with a more porous, interconnected cell structure that allows air and moisture to move through the material. This provides better sustained cooling than gel-infused foam because the airflow is continuous rather than relying on a finite heat-absorption capacity. The tradeoff is that open-cell foams are typically less dense, which can affect durability and support.
Effectiveness: Good for Short-Duration Cooling
PCMs are engineered materials that absorb heat energy as they transition from solid to liquid, typically activating at skin temperatures of 28-32 degrees Celsius. During this phase transition, the PCM absorbs a significant amount of heat without increasing in temperature, creating a cooling sensation. Research has shown PCMs can lower skin temperature and improve heat dissipation by up to 25.6% compared to conventional mattress surfaces. However, once the PCM has fully transitioned to liquid, it stops absorbing heat and must cool down and re-solidify before working again. PCMs work best in combination with other cooling strategies rather than as a standalone solution.
Effectiveness: Excellent
A pocketed coil support core creates 6-8 inches of open air space within the mattress. Warm air rises naturally from the sleep surface through the comfort layers and is replaced by cooler ambient air drawn through the sides and bottom of the mattress. This passive convection cycle operates continuously throughout the night without any mechanical components, never runs out of capacity, and never needs to be recharged. Coil-based airflow is the single most effective cooling feature in any mattress construction.
Effectiveness: Good
Natural fibres, particularly wool, cotton, silk, and TENCEL (lyocell), regulate temperature and moisture far more effectively than synthetic polyester covers. Wool can absorb up to 30% of its weight in moisture without feeling damp and naturally regulates temperature in both warm and cool conditions. TENCEL is 50-70% more moisture absorbent than cotton (Lenzing AG fibre data) and wicks moisture away from the skin surface, which promotes evaporative cooling. Natural fibre covers and comfort layers provide genuine, all-night cooling that complements other technologies.
8 min read
Mattress Types Ranked by Cooling Performance
Based on the principles of heat transfer and the technologies available, here is how mattress types rank for hot sleepers, from coolest to warmest:
1. Latex hybrid (coils + natural latex comfort layers): Natural latex has an inherently open-cell structure with pinholes that promote airflow. Combined with a pocketed coil base, this construction provides continuous passive cooling through both the comfort layer and the support core. Latex also sleeps cooler than memory foam because it does not conform as closely, leaving small air pockets between the body and the mattress surface.
2. Traditional hybrid (coils + foam comfort layers): Even with memory foam comfort layers, the pocketed coil base provides significant cooling through convective airflow. The heat-trapping properties of the foam are partially offset by the air circulation below. Hybrids with gel-infused or open-cell foam comfort layers rank closer to latex hybrids in cooling performance.
3. Innerspring: Traditional innerspring mattresses with minimal comfort layers and interconnected coils sleep cool because there is very little foam to trap heat. However, they sacrifice pressure relief and motion isolation for this cooling advantage, which makes them unsuitable for many sleepers.
4. All-foam with cooling technology: All-foam mattresses with gel-infused foam, open-cell foam, or PCM covers can moderate heat retention but cannot match the cooling performance of any coil-based construction. Without the convective airflow channel that coils provide, heat must dissipate through the foam itself, which is inherently slow.
5. Traditional all-foam (memory foam): Dense, closed-cell memory foam without cooling modifications is the warmest mattress type. The close body conformity that makes memory foam excellent for pressure relief also maximizes the skin-to-foam contact area, trapping heat efficiently. This is the mattress type most hot sleepers need to avoid.
The Canadian Factor: Seasonal Temperature Challenges
Hot sleeping in Canada has a seasonal dimension that many American-focused mattress guides overlook. While summer heat is an obvious concern, Canadian winters present a different but equally problematic thermal challenge.
During Ontario winters, when outdoor temperatures regularly drop below -10 degrees Celsius, most Canadian homes run their heating systems continuously. Forced-air heating creates warm, dry indoor environments that can push bedroom temperatures above the optimal 15.6-19.4 degree range, even with the thermostat set reasonably low. Dry heated air also dries out nasal passages and skin, which triggers compensatory vasodilation that increases skin temperature and amplifies the sensation of sleeping hot. Many Canadians report sleeping hotter in January than in July because they do not realize their heating system is overheating the bedroom.
Health Canada recommends indoor humidity between 30-50%, but Canadian homes with forced-air heating routinely drop to 20-30% relative humidity in winter without a humidifier. This low humidity not only dries out airways (contributing to snoring and congestion) but also reduces the effectiveness of evaporative cooling from the skin. A breathable mattress helps compensate by allowing moisture (sweat) to wick away from the body rather than pooling at the mattress surface, where it creates a clammy, uncomfortable sensation.
A mattress that performs well for hot sleepers in Canada needs to regulate temperature across both extremes: preventing heat buildup during warm summer nights and managing the dry-heat environment created by winter heating systems.
Night Sweats, Menopause, and Medical Hot Sleeping
For some Canadians, sleeping hot is not just a comfort issue but a medical one. Night sweats (sleep hyperhidrosis) have specific medical causes that a mattress can help manage but not treat.
Menopause and perimenopause: Hot flashes and night sweats affect up to 80% of women going through menopause, with symptoms often lasting 7-10 years. During a night sweat episode, the body's thermostat (the hypothalamus) temporarily raises the set point, triggering vasodilation and sweating to shed the perceived excess heat. A cooling mattress with moisture-wicking properties helps manage the aftermath of these episodes by drawing sweat away from the body and promoting rapid evaporation. Research suggests that cooling sleep surfaces can reduce the frequency and severity of menopause-related sleep disturbances by over 50%.
Medications: Numerous common medications cause night sweats as a side effect, including antidepressants (SSRIs affect up to 20% of users), certain blood pressure medications, hormonal therapies, and some diabetes medications. If you are taking any of these medications and sleeping hot, the mattress should be part of your management strategy alongside discussing the issue with your prescribing physician.
Hyperhidrosis: Primary hyperhidrosis (excessive sweating without an underlying medical cause) affects approximately 3% of the Canadian population. For these individuals, a mattress with exceptional moisture management is essential. Look for mattresses with removable, machine-washable covers, moisture-wicking natural fibre layers, and waterproof mattress protectors that do not trap heat (some waterproof protectors are vinyl-based and create more heat problems than they solve).
Beyond the Mattress: Complete Cool Sleep System
While the mattress is the foundation, a complete cool sleep system addresses temperature from every angle:
Pillow: Your head generates a disproportionate amount of heat relative to its size. A cooling pillow with gel-infused foam, ventilated latex, or phase-change material covers can reduce head and neck temperature by 2-4 degrees. Look for perforated or ventilated designs that allow airflow through the pillow, not just cooling surface treatments.
Sheets and bedding: Cotton percale (crisp, breathable), bamboo/TENCEL (moisture-wicking), and linen (loosely woven, excellent airflow) are the coolest sheet materials. Avoid polyester or microfibre sheets, which trap heat and moisture. Thread count is less important than fibre type for cooling; a 300-thread-count cotton percale sheet will sleep cooler than a 600-thread-count sateen.
Mattress protector: If you use a waterproof protector (recommended to protect your investment), choose one made with a breathable polyurethane membrane rather than vinyl or PVC. Breathable protectors allow air and moisture vapour to pass through while blocking liquids, maintaining the cooling properties of the mattress surface.
Bedroom environment: Set the thermostat to 18 degrees Celsius (65 degrees Fahrenheit) for the bedroom, use a fan to promote air circulation (even in air-conditioned homes), and consider blackout curtains that block solar heat gain during summer months. In winter, keep bedroom vents partially closed to prevent overheating while the rest of the home is heated normally.
Our Brantford Showroom Recommendations
Cooling performance is one of the hardest mattress features to evaluate from an online description. At Mattress Miracle in Brantford, you can lie on each mattress and feel how the surface temperature responds to your body. We will explain the cooling features of each model and help you compare how different constructions manage heat, so you can make a decision based on how the mattress actually feels, not just how it is described.
Restonic Luxury Silk & Wool (from $2,395): Our top recommendation for hot sleepers. The natural silk and wool comfort layers provide exceptional temperature regulation and moisture wicking that synthetic materials cannot match. Wool regulates temperature in both warm and cool conditions, absorbing moisture vapour from your body and releasing it into the air. Combined with 884 individually pocketed coils for airflow, this mattress maintains a neutral-to-cool sleep surface across Canadian seasons.
Restonic ComfortCare (from $1,125): With 1,222 individually pocketed coils creating extensive airflow through the support core, the ComfortCare sleeps significantly cooler than any all-foam mattress at a similar price. The multi-layer comfort system includes materials designed for breathability while delivering the medium-firm support most sleepers need. This is our best value option for hot sleepers who want a proven cooling construction without paying a premium for specialty materials.
Restonic Revive St. Charles (from $3,150): The St. Charles combines 1,188 pocketed coils with gel-infused foam comfort layers that provide both immediate cooling contact and sustained airflow through the coil system. The zoned support design means firmer coils under the lumbar region and softer coils under the shoulders, providing excellent spinal alignment alongside its cooling properties. Recommended for hot sleepers who also need targeted back support.
Frequently Asked Questions
Yes, but the degree of cooling varies enormously by technology. Pocketed coil airflow provides the most consistent, all-night cooling because it relies on passive convection rather than finite heat-absorption capacity. Gel-infused foam provides moderate initial cooling that diminishes over 1-2 hours. Phase-change materials provide significant short-duration cooling during their phase transition. The most effective cooling mattresses combine multiple approaches: a coil base for continuous airflow, gel or open-cell foam for surface cooling, and natural fibre covers for moisture management.
Traditional closed-cell memory foam is the warmest mattress material available, and hot sleepers should generally avoid all-foam mattresses made primarily with it. However, memory foam with cooling modifications (gel-infused, open-cell, or graphite-infused) sleeps meaningfully cooler. A hybrid mattress that uses a thin layer of modified memory foam over a pocketed coil base can provide the pressure relief of memory foam with the cooling of a coil system.
Natural latex is the best single material for hot sleepers because it combines an open-cell structure, natural breathability, responsive contouring (which leaves cooling air pockets), and excellent moisture management. However, the best overall construction is a hybrid with pocketed coils (for airflow) and either latex or gel foam comfort layers, with a natural fibre cover for moisture wicking.
Canadian homes with forced-air heating often overheat bedrooms during winter. The heated air dries indoor humidity to 20-30% (Health Canada recommends 30-50%), which reduces evaporative cooling from the skin and can raise the bedroom temperature above the optimal 15.6-19.4 degrees Celsius range. Try closing or partially closing bedroom heating vents, using a humidifier, and keeping the bedroom door slightly open for air circulation.
A mattress cannot prevent hot flashes, but it can significantly improve how quickly your body cools down after one. A cooling mattress with moisture-wicking properties draws sweat away from the skin and promotes rapid evaporation, reducing the duration of discomfort. Research suggests cooling sleep surfaces can reduce menopause-related sleep disruptions by over 50%. Natural wool and TENCEL covers are particularly effective for moisture management.
Active cooling systems (water-based cooling pads, thermoelectric coolers) provide the most precise temperature control, but they are expensive, require electricity, and add complexity. For most hot sleepers, a well-constructed hybrid mattress with a breathable cover and natural fibre layers provides sufficient cooling without the maintenance and cost of an active system. Reserve active cooling for medical-grade hot sleeping (severe night sweats, menopause, or temperature-sensitive conditions).
Sources and References
- Okamoto-Mizuno, K. & Mizuno, K. (2012). "Effects of thermal environment on sleep and circadian rhythm." Journal of Physiological Anthropology, 31(1), 14.
- Haskell, E.H., et al. (1981). "The effects of high and low ambient temperatures on human sleep stages." Electroencephalography and Clinical Neurophysiology, 51(5), 494-501.
- Krauchi, K. (2007). "The thermophysiological cascade leading to sleep initiation in relation to phase of entrainment." Sleep Medicine Reviews, 11(6), 439-451.
- Ames, M.E., et al. (2024). "Sleeping for One Week on a Temperature-Controlled Mattress Cover Improves Sleep and Cardiovascular Recovery." Sensors, 24(8), 2416.
- Lenzing AG. TENCEL fibre data: 50-70% more moisture absorbent than cotton.
- Health Canada. Indoor humidity recommendation: 30-50% relative humidity.
- Sleep Foundation (2026). Best Temperature for Sleep: thermoregulation guidelines and mattress cooling evaluation criteria.
At Mattress Miracle in Brantford, we understand that sleeping hot is not just uncomfortable; it actively degrades your sleep quality and your health. Our Restonic hybrid mattresses feature individually pocketed coils for continuous airflow, breathable comfort layers, and natural fibre options that regulate temperature through every Canadian season. Visit us at 441 1/2 West St, Brantford, ON or call (519) 770-0001 to feel the cooling difference for yourself. Serving Brantford, Hamilton, Cambridge, Kitchener-Waterloo, and surrounding communities since 1987.
441 1/2 West Street, Brantford | (519) 770-0001
Mon-Wed 10-6 | Thu-Fri 10-7 | Sat 10-5 | Sun 12-4
Hot sleepers need specific features to stay cool all night. Come visit us at 441 1/2 West Street and try our most breathable options in person before you commit.
Shop: All Mattresses at Mattress Miracle
Find Your Perfect Mattress at Mattress Miracle
We are a family-owned mattress store in Brantford, helping our community sleep better since 1987. Come try mattresses in person and get honest, no-pressure advice.
441 1/2 West Street, Brantford, Ontario
Call 519-770-0001Frequently Asked Questions
What mattress type sleeps coolest for hot sleepers in Canada?
Do memory foam mattresses cause overheating?
What mattress materials help regulate body temperature during sleep?
Can a mattress topper help a hot sleeper stay cooler?
What bedroom temperature is ideal for sleep?
Visit Our Brantford Showroom
We are located at 441 1/2 West Street in downtown Brantford. Free parking available. Our team does not work on commission, so you get honest advice based on your needs.
Mattress Miracle -- 441 1/2 West Street, Brantford, ON -- (519) 770-0001
Hours: Monday-Wednesday 10am-6pm, Thursday-Friday 10am-7pm, Saturday 10am-5pm, Sunday 12pm-4pm.
Come in and let our team help you find the right mattress for your needs. No pressure, no commission.
Shop This Topic at Mattress Miracle
Cooling picks we carry at Mattress Miracle:
Or cooling mattresses in our Brantford showroom.