Top Quilt Glossary

By topquilt.com · Updated Oct 21, 2026 · 7 min read

Quilt makers, hammock forums and spec sheets use a lot of shorthand. This top quilt glossary translates it into plain English so you can read product pages with confidence. Terms are grouped alphabetically; jump to a letter using the table of contents.

A quick orientation before you dive in: terms about insulation (fill power, fill weight, overfill, loft) tell you how warm a quilt is. Terms about construction (baffles, footbox, draft collar, differential cut) tell you how well that warmth stays around you. Terms about the rest of the system (R-value, underquilt, ridgeline, top cover) explain what happens beneath and around the quilt. Most cold nights trace back to a gap in one of those three groups, not to the quilt alone.

A–B

APEX (Climashield APEX) — A continuous-filament synthetic insulation sold in weights such as 2.5, 3.6 and 5.0 oz/yd². Common in synthetic and DIY quilts. See Climashield APEX explained.

Baffle — An internal wall of mesh or fabric that creates chambers to hold down in place and allow full loft. See quilt baffles explained.

Baffle height — The height of the internal baffle walls, which sets the maximum loft a chamber can reach.

Base layer — Thin long underwear, usually merino or synthetic, worn to sleep. See sleep clothing for quilts.

Bridge hammock — A hammock with spreader bars at each end for a flatter lay. Compare in gathered end vs bridge hammock.

C

Bag liner — See liner (sleep).

CBS (cold butt syndrome) — Cold from compressed insulation under you in a hammock. See cold butt syndrome.

Chevron baffles — V-shaped baffles that help keep down from migrating toward the sides.

Comfort rating — The temperature at which a typical cold sleeper should feel comfortable. Few quilts are lab tested to it. See temperature ratings.

Compression sack — A stuff sack with straps that shrinks a quilt for packing. Use only during the hike. See how to pack a quilt.

Condensation — Moisture from your breath and body that collects in or on insulation, especially on cold, still nights. Over multiple nights it can noticeably reduce down loft.

Continuous baffles — Horizontal baffles open at the sides so you can shift down from top to bottom for warmer or cooler nights.

Cottage brand — A small, often custom-order maker such as Hammock Gear or Enlightened Equipment. See custom vs stock quilts.

Cuben / DCF — Dyneema Composite Fabric, a very light laminate used for tarps and stuff sacks, rarely for quilts because it does not breathe.

D

Denier (D) — A measure of yarn thickness. A 10D shell is lighter and more delicate than a 20D one. See quilt shell fabrics.

Differential cut — Cutting the outer shell larger than the liner so the insulation is not compressed when the quilt curves around you.

Down cluster — The fluffy, three-dimensional plumule from a duck or goose that traps air. Feathers are flat and much less warm.

Downproof — Fabric woven or treated tightly enough to keep down from poking through.

Draft collar — An insulated tube or flap at the neck of a quilt that blocks warm-air escape. See draft collar guide.

Draft tube — An insulated strip behind a zipper or along a quilt's edge that blocks cold air.

Duck down vs goose down — Both work; goose is more common at the highest fill powers. See duck vs goose down.

DWR — Durable water repellent finish that makes water bead on the shell fabric.

E–F

Edge-stitched — Construction where insulation is sewn only at the perimeter, typical of APEX quilts.

Fill power (FP) — Cubic inches one ounce of down lofts to in a standard test, e.g. 800, 850 or 950. See fill power explained.

Fill weight — Ounces of insulation inside a quilt; the best single warmth indicator. See fill weight and overfill.

Footbox — The enclosed foot end of a quilt, sewn closed or closable with a drawcord and zipper. See footbox guide.

Fill (synthetic) — Polyester-based insulation such as APEX. Rated by weight per square yard rather than fill power. See down vs synthetic quilts.

G–H

Gathered-end hammock — The classic hammock style where fabric is bunched at each end and you lie on a diagonal.

Hammock sock — A full-length fabric sleeve over a hammock that blocks wind. See top covers and hammock socks.

Hydrophobic down — Down treated to resist absorbing moisture. Helps, but is not waterproof. See hydrophobic down.

Hood (down hood) — A separate insulated hood worn with a quilt in cold weather, replacing a sleeping bag's hood.

Insulated pad — A sleeping pad with internal insulation or reflective layers that raises its R-value. See best sleeping pads for quilts.

L

Layering — Combining quilts, liners or clothing to extend a sleep system's range. See quilt layering system.

Limit rating — The lowest temperature at which a typical warm sleeper can stay in balance curled up. Colder than comfort.

Liner (fabric) — The inner fabric of a quilt that touches you.

Liner (sleep) — A separate sack or wrap of silk, fleece or synthetic that adds a few degrees and keeps the quilt clean.

Loft — The thickness of insulation; trapped still air is what keeps you warm. See restore quilt loft.

M–O

Mummy bag — A tapered sleeping bag with a hood and zipper. Compare in top quilt vs sleeping bag.

Open footbox — A footbox that unzips flat so the quilt opens like a blanket. See open vs sewn footbox.

Overfill — Extra down added beyond the base spec to boost loft and warmth. See overfill.

Overquilt — A thin, usually synthetic quilt laid over a main quilt for warmth and condensation management.

P

Pad straps — Elastic or cord straps that hold a quilt's edges to a sleeping pad. See pad attachment systems.

Partial zipper — A short zipper at the foot of a quilt that closes the footbox.

Puffy — An insulated jacket; doubles as sleep insulation with a quilt.

R

R-value — A sleeping pad's resistance to heat flow, now measured under ASTM F3340. See sleeping pad R-value.

RDS — Responsible Down Standard, a certification of animal welfare in down sourcing. See RDS explained.

Ridgeline — A cord strung between hammock ends, used to set a consistent sag and hang gear.

Ripstop — Fabric with a reinforcing grid that stops small tears from spreading.

S

Sewn-through — Construction where shell and liner are stitched directly together, creating thin spots at seams. See sewn-through vs baffled.

Shell — The outer fabric of a quilt.

Shingled construction — Overlapping layers of synthetic insulation that avoid seam cold spots.

Shock cord — Elastic cord used in draft collars, neck closures and pad straps.

Snap closure — Snaps at a quilt's neck or foot used to close it around you.

Structural ridgeline — See ridgeline; a fixed-length line that sets the hammock's sag.

Stuff sack — A packing sack. Do not use it for long-term storage. See how to store a quilt.

Suspension — The straps and hardware that hang a hammock from trees.

T

Taper — How much a quilt narrows from shoulders to feet.

Temperature rating — The maker's estimate of the lowest temperature for a quilt. Rarely standardized. See temperature ratings.

Top cover — A wind-blocking fabric layer over the top of a hammock. See top covers.

Top quilt (TQ) — A backless sleeping bag alternative that covers your top while a pad or underquilt insulates beneath. See what is a top quilt.

U–Z

Underquilt (UQ) — Insulation hung beneath a hammock. See underquilt guide.

Vapor barrier liner (VBL) — A non-breathable liner for very cold weather that stops body moisture from entering insulation.

Vertical baffles — Baffles running head to foot, which keep down in place when the quilt is draped.

Wearable quilt — A quilt with a head hole or snaps to be worn as a poncho. See best wearable quilts.

Width — Usually the quilt's flat width at the shoulders; critical for side sleepers. See sizing guide.

Wrap — How much a quilt can tuck under your sides. More width means better wrap.

Zipperless — A quilt with a sewn footbox and snaps or cord only, saving weight.

Common abbreviations

Where to go next

If you are just getting started, read what is a top quilt and our first backpacking quilt guide. Hammock campers should continue with the hammock insulation guide. Ready to compare models? See how to choose a top quilt.