Deflating and packing up
When packing up, you first open the main valve, let the air out and roll the boat up towards the valve.
Materials and technology
TPU, denier, welded seams, valves and inflating: everything about boat fabrics and technology.
27 terms in this topic
All terms
Setting up
A packraft is set up in a few minutes: lay it out, insert the gear, inflate with the inflation bag, top up, then inflate seat and backrest.
Operating pressure
Packrafts work with very low air pressure. Firm but not rock-hard is the goal.
Inflation bag
The inflation bag is a light nylon bag you use to inflate a packraft in a few minutes, without any pump.
Inflation hose
A piece of hose from the hardware store that fits the mouth valve makes topping up on the water much easier.
bluesign
bluesign is a certification system for textiles that limits the use of hazardous chemicals in production.
Boston valve
A Boston valve is a two-part valve: the top part has a one-way flap for inflating, and if you unscrew the whole valve, the air rushes out quickly.
DEET (insect repellent)
DEET is an active ingredient in many insect repellents and attacks the boat fabric: the material becomes cloudy, sticky and soft.
Denier (D)
Denier is a unit for the yarn thickness of a fabric. The higher the number, the thicker, tougher and heavier the fabric.
Dyneema Composite
Dyneema Composite Fabric is an extremely light laminate used in ultralight gear such as dry bags and tents.
Single and double coated fabric
Single-coated fabric has the TPU layer on one side only, double-coated fabric on both. That matters for repairs.
Hand pump and electric pump
A hand or electric pump gives you more pressure than an inflation bag and your lungs. That's worth it for large tandems and in whitewater.
Main valve
The packraft is inflated and deflated through the main valve. Many valves have a one-way flap so the air doesn't escape while you inflate.
High-frequency welding
In high-frequency welding, plastic is heated by an electromagnetic field and joined under pressure, without any glue.
Hydrolysis
Hydrolysis is the breakdown of plastic by moisture and heat. In packrafts it mainly affects airtight zippers that are stored wet.
Hypalon
Hypalon is a very tough, UV-resistant rubber coating used on large rafts and folding boats.
Kevlar and aramid
Kevlar is a brand name for aramid fibres. In some packraft floors, aramid is woven into the nylon to make them more cut- and abrasion-resistant.
Leafield valve
Leafield valves are sturdy valves from raft building. They are mainly found on heavy whitewater and PVC boats.
Mouth and topping-off valve
A small mouth or topping-off valve lets you top up by mouth, for example when the boat softens in cold water.
Nylon (polyamide)
Nylon is the base fabric of almost all packrafts. It provides tear strength, the coating provides airtightness.
Plus material (Anfibio)
Anfibio uses “Plus” for versions with tougher tube fabric, namely 420 instead of 210 denier.
PVC
PVC is a cheap, heavy boat material used mainly for pool toys and sturdy rafts.
Salt water
Packrafts made of TPU nylon are saltwater-resistant. After trips on the sea you should still rinse them with fresh water.
Welded seam
On TPU packrafts the fabric panels are usually welded rather than sewn or glued. That saves weight and stays airtight.
Temperature effect (pressure loss in cold water)
If a packraft is inflated in warm air and then put into cold water, the air cools, contracts and the boat gets softer. Usually that's not a leak.
Learn more: Temperature effect (pressure loss in cold water)
TPU (thermoplastic polyurethane)
TPU is the coating that makes the nylon fabric of modern packrafts air- and watertight. It's light, abrasion-resistant and can be welded.
UV resistance
Sunlight ages plastics over time. Packrafts should therefore not lie or be stored in the sun permanently.