Understanding Mattress Springs
Springs have been used in mattresses since the 1870s, and they remain the most popular support system in the UK. But not all springs are created equal.
Open Coil (Bonnell) Springs
The oldest and simplest design. Open coil mattresses use a single interconnected wire frame, meaning all springs are linked together. When you press down on one area, the surrounding springs respond too.
Pros: Affordable, widely available, good airflow
Cons: Partner disturbance (movement transfers across the mattress), less targeted support, tends to sag faster
Typical count: 300-400 springs in a double mattress
Best for: Guest beds, children, budget-conscious buyers
Pocket Springs
Each spring is individually wrapped in its own fabric pocket, so it moves independently. This is the key advantage: pocket springs respond to your body shape without affecting the area next to you.
Pros: Excellent motion isolation, targeted support, longer lifespan
Cons: More expensive than open coil, heavier
Typical count: 800-2000+ in a double mattress
Best for: Couples, people with back pain, anyone wanting better support
Micro-Pocket Springs
Smaller diameter springs (often 2-3cm) used in addition to standard pocket springs. They are typically found in a comfort layer on top of the main spring unit, providing finer contouring to body curves.
Typical count: 2000-6000+ when combined with standard pocket springs
Best for: Premium mattresses, side sleepers who need pressure relief
Zoned Springs
A pocket spring system where the spring tension varies across the mattress surface. Typically firmer in the centre third (lumbar zone) and softer at the head and feet. This provides targeted support where your body needs it most.
Key Fact: Pocket springs move independently, eliminating partner disturbance. Spring count matters, but construction quality and wire gauge are equally important indicators of mattress quality.
