Mattress Coil Technology and Fire Safety

Mattress Coil Technology and Fire Safety

Quick Answer: Quick answer: Pocket coils are the superior coil technology for most sleepers, offering independent motion isolation, targeted pressure response, and excellent airflow. Coil gauge (wire thickness) determines firmness, while coil count affects how finely the mattress responds to your body. For fire safety, Canadian law (SOR/2016-183) requires all mattresses to pass ignition testing, but compliance can be achieved without chemical flame retardants using natural wool barriers or inherently flame-resistant materials.

8 min read

Four Coil Types Compared

Bonnell Coils

The oldest and most common spring design. Bonnell coils have an hourglass shape, wider at top and bottom, thinner in the middle. The thin centre section flexes under light pressure while the wider sections handle heavier loads. Individual coils are knotted at each end and connected to neighbours via helical wire.

  • Pros: Affordable, durable, good for budget mattresses
  • Cons: Connected design transfers motion across the entire mattress. When one area compresses, adjacent areas shift. Poor motion isolation for couples
  • Best for: Budget single-sleeper mattresses, guest beds

Offset Coils

An evolution of the Bonnell design. The top and bottom of each hourglass coil are flattened, creating a hinging action when pressure is applied. This allows the coil to conform more closely to body contours while maintaining structural durability.

  • Pros: Better conformance than Bonnell, more durable, better at following body curves
  • Cons: Still connected (motion transfer), more expensive than Bonnell, less common in modern mattresses
  • Best for: Mid-range mattresses where budget prevents pocket coils

Continuous Wire Coils

A single wire is formed into rows of S-shaped coils, connected by helical wires. This creates a highly durable, interconnected support system. The single-wire construction means there are no individual coil connection points to fail.

  • Pros: Extremely durable, high coil counts (1,000+ in queen), cost-effective manufacturing
  • Cons: Maximum motion transfer (the entire surface moves as one unit), least conforming coil type, can feel rigid
  • Best for: Institutional use (hotels, dormitories) where durability outweighs comfort

Pocket Coils (Individually Wrapped)

Each coil is individually wrapped in its own fabric pocket. Coils compress independently, responding to pressure point by point rather than as a connected surface. This is the dominant technology in modern hybrid mattresses.

  • Pros: Excellent motion isolation (each coil moves independently), precise body conformance, superior airflow between individual pockets, compatible with all comfort layer types
  • Cons: Most expensive coil system, requires more manufacturing precision, heavier than other coil types
  • Best for: Couples, side sleepers, anyone who wants targeted support and motion isolation
Coil Type Comparison Summary
Feature Bonnell Offset Continuous Pocket
Motion isolation Poor Fair Poor Excellent
Conformance Low Moderate Low High
Airflow Good Good Good Excellent
Durability Good Very good Excellent Very good
Edge support Moderate Good Good Good (with reinforcement)
Cost $ $$ $ $$$
Common in 2026 Budget only Rare Hotels/institutional Dominant standard

"Every mattress we sell uses pocket coils. The technology is so superior for sleep quality that there is no reason to compromise with connected coil systems anymore. The price gap has narrowed enough that pocket coils are accessible at every budget level."

, Brad, Owner, Mattress Miracle (since 1997)

Understanding Coil Gauge

Mattress Coil Technology and Fire Safety Materials Guide for Canada (2026)

Coil gauge measures the thickness of the wire used to form each coil. Confusingly, lower gauge numbers mean thicker, firmer wire. This is the opposite of what most people expect.

Coil Gauge and Firmness
Gauge Wire Thickness Feel Best For
12-13 Thickest Very firm, heavy-duty Heavier sleepers (250+ lbs), bariatric
13-14 Thick Firm to medium-firm Back sleepers, stomach sleepers, most adults
14-15 Medium Medium General use, combination sleepers
15-16 Thinner Medium-soft to soft Side sleepers, lightweight sleepers
16-17 Thin Soft, highly responsive Micro-coils in comfort layers

Zoned Coil Systems

Modern pocket coil mattresses often use different gauge coils in different zones. A typical zoned arrangement uses softer (higher gauge) coils in the shoulder zone for pressure relief and firmer (lower gauge) coils in the lumbar zone for spinal support. This provides targeted support without requiring the entire mattress to be one firmness level.

What Coil Count Actually Means

Coil count is heavily marketed but frequently misunderstood. A higher number does not automatically mean a better mattress.

The Coil Count Truth

Beyond approximately 800 pocket coils in a queen-size mattress, additional coils provide diminishing returns. The difference between 800 and 1,200 coils is noticeable (finer-grained response). The difference between 1,200 and 2,000 coils is minimal for most sleepers. Some manufacturers achieve extremely high coil counts by using multiple layers of micro-coils, which serves a different purpose (comfort layer responsiveness) than the support core coil count.

Pocket Coil Count Guide (Queen Size)
Coil Count Response Quality Who Benefits Typical Price Impact
400-600 Basic (adequate for most) Budget-conscious, average builds Baseline
600-800 Good (noticeable improvement) Most adults, couples +$100-200
800-1,200 Very good (fine-grained support) Side sleepers, varied body zones +$200-400
1,200+ Excellent (premium response) Maximum conformance priority +$400+

Canadian Fire Safety Regulations

Every mattress sold in Canada must comply with SOR/2016-183, the federal Mattresses Regulations under the Canada Consumer Product Safety Act. This regulation is not optional and applies to all manufacturers, importers, and retailers.

The Test Standard

Mattresses must pass the cigarette ignition test described in CAN/CGSB-4.2 No. 27.7. The test requires that:

  • Charring must not extend more than 50 mm from the cigarette placement point
  • Combustion must cease within 10 minutes of the cigarette being placed
  • The mattress must not produce sustained smouldering or open flame

Health Canada's Position on Chemical Flame Retardants

Importantly, Health Canada has stated that compliance with fire safety standards can be achieved without chemical flame retardants. The agency actively encourages manufacturers to use safe, non-chemical alternatives such as inherently flame-resistant materials (wool, treated polyester) or physical fire barriers.

Fire Barrier Materials Compared

Fire Barrier Materials in Canadian Mattresses
Barrier Material Method Health Concerns Sleep Impact Cost
Natural wool Inherent fire resistance None (natural fibre) Positive (thermoregulation, moisture wicking) Higher
Treated rayon/cellulose Chemical treatment of plant fibre Minimal (silica-based treatment) Neutral Moderate
Inherently FR polyester Flame-resistant polymer Low (no added chemicals) Neutral Moderate
Fiberglass sock Physical barrier woven from glass fibres Risk of fibre release if cover removed or damaged Neutral when contained Low
Chemical FR spray Chemical treatment applied to foam or fabric Higher (off-gassing concerns, endocrine disruptors) Potentially negative Low
The Fiberglass Concern

Some budget mattresses use a fiberglass fire barrier sock woven directly around the foam core. If the mattress cover is removed or damaged, microscopic glass fibres can escape and spread throughout the bedroom. These fibres irritate skin, eyes, and lungs. Always check the care label: if it says "Do not remove cover," it may indicate a fiberglass barrier. This is primarily a concern with online-only, budget mattress brands rather than quality in-store brands.

"We only carry mattresses that use non-fiberglass fire barriers. Our Restonic mattresses use safe barrier systems that meet all Canadian fire safety standards without fiberglass or chemical flame retardants. That is a line we will not cross."

, Brad, Owner, Mattress Miracle (since 1997)

Restonic Coil Specifications

Restonic Lineup: Coil Specifications and Fire Safety
Model Coil Type Coil Count (Queen) Zoned Fire Barrier Price (Queen)
ComfortCare Pocket coil 1,222 Yes Non-fiberglass $1,619
Revive Reflections ET Pocket coil 1,200 Yes Non-fiberglass $2,395
Luxury Silk and Wool Pocket coil 884 Yes (zoned) Natural wool $2,395
Revive Tiffany Rose Pocket coil 1,188 Yes Non-fiberglass $2,995
Revive St Charles Pocket coil 1,188 Yes Non-fiberglass $3,150

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Questions About What Is Inside Your Mattress?

Every mattress at Mattress Miracle comes with full transparency on coil type, gauge, count, and fire barrier materials. No hidden fiberglass, no chemical flame retardants. Visit us at 441 1/2 West St, Brantford, or call (519) 753-9109.

Visit Our Brantford Showroom

We are located at 441½ 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 , 441½ West Street, Brantford, ON · (519) 770-0001

Hours: Monday–Wednesday 10am–6pm, Thursday–Friday 10am–7pm, Saturday 10am–5pm, Sunday 12pm–4pm.

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