Woken up shivering in your hammock, even with a good sleeping bag? Yeah, that cold backside feeling is a real trip ruiner. Airflow underneath, while great in summer, will suck the warmth right out of you when temps dip. Your sleeping bag gets compressed under your body, losing most of its insulating power just where you need it most. So, what’s the fix?
Why you need bottom insulation
Hammocks are amazing, but they leave your underside exposed. Unlike sleeping on the ground, where the earth offers some (minor) insulation, a hammock lets air circulate freely all around you. This is called convective heat loss. Even a slight breeze can make you feel much colder than the actual air temperature.
Your sleeping bag, designed to trap warm air, gets squished flat beneath you. No loft means no trapped air, and no trapped air means no insulation. That’s why your back and butt get so chilly. You need something specifically designed to insulate the bottom of your hammock.
Underquilts the dedicated solution
An underquilt is basically a blanket that hangs outside and underneath your hammock. It creates a pocket of still, warm air, just like your sleeping bag does on top. Because it’s not compressed by your body, it maintains its full loft and insulating ability.
- Pros:
- Superior warmth and comfort. No cold spots.
- Doesn’t shift around like a pad can.
- Allows your sleeping bag to fully loft inside the hammock.
- Often lighter and more compressible than a comparable pad for the same warmth.
- Cons:
- Can be pricey.
- Specific to hammock camping; not as versatile as a pad.
- Takes a little practice to set up just right.
Underquilts come with different temperature ratings and fill materials, usually down or synthetic. Down is lighter and more compressible for its warmth, but loses insulation if it gets wet and costs more. Synthetics are bulkier and heavier, but handle moisture better and are generally less expensive.
Can sleeping pads work
Sure, you can use a sleeping pad in a hammock. Many folks start this way. You just pop it inside the hammock with you. Closed-cell foam (CCF) pads are common, as are some inflatable pads.
- Pros:
- You probably already own one.
- Can add a bit of structure to the hammock lay.
- Protects your hammock from pointy bits on your clothes.
- Cons:
- They tend to shift around, leaving cold spots. A lot.
- Can make you feel sweaty where you contact the pad.
- Wider pads can create “wings” that fold up around you, feeling restrictive.
- Narrow pads don’t protect your shoulders or arms well.
- Inflatables can be noisy or even puncture.
Pads just aren’t designed for the curved shape of a hammock. They work best on flat surfaces. While a pad is better than nothing, its performance in a hammock, especially as temperatures drop, is often less than ideal. Some people find double-layer hammocks help keep pads in place a bit better.
Temperature performance compared
So, how do these two options really stack up when the mercury drops? An underquilt is almost always going to keep you warmer and more comfortable than a pad in a hammock, especially in cooler conditions. Lets look at a general comparison…
| Temperature Range (°F/°C) | Underquilt Effectiveness | Pad Effectiveness | Key Considerations |
|---|---|---|---|
| 60°+ / 15°C+ | Good, can be overkill | Decent, may cause sweat | Light UQ or no UQ needed. Thin CCF pad might suffice. |
| 40-60° / 4-15°C | Excellent | Okay, can shift | 20-40°F UQ ideal. Inflatables better than CCF here. |
| 20-40° / -6-4°C | Essential | Poor, significant gaps | 0-20°F UQ. Pads really struggle with consistent coverage. |
| Below 20° / Below -6°C | Critical | Not recommended | Sub-zero UQ, possibly with a thin pad inside for extreme. |
As you can see, once you get below about 50°F (10°C), an underquilt really starts to shine. Pads can work in a pinch for milder weather, but for serious three-season or 2025 winter hammock camping, an underquilt is the way to go for consistent, reliable warmth. No more cold butt syndrome!