Big Agnes Copper Spur HV UL1 vs Sea to Summit Alto TR1

Two shelters, measured against each other on the figures that decide whether they work on a bike.

The short answer

The Copper Spur HV UL1 takes pitching on hard ground; the Alto TR1 takes floor space and headroom. Their pole sets are close enough that neither wins on the bars, so this comes down to what you want from the shelter itself.

Assembled from the differences below rather than written over them. Every figure is a published measurement or computed from one — nobody here has used either one.

Where they differ

3 of the 7 things we can measure come out differently.

Pitching

Copper Spur HV UL1 needs less from the ground
Big Agnes Copper Spur HV UL1
Freestanding
Sea to Summit Alto TR1
semi

Freestanding matters on a bike trip more than on a hike: gravel bars, wooden platforms and hardpack are where you end up when you are following a road, and none of them take a stake.

Floor area

0.13m² more floor in the Alto TR1
Big Agnes Copper Spur HV UL1
224 × 97cm — 2.16m²
Sea to Summit Alto TR1
215 × 107cm — 2.29m²

Inner length by inner width as published. On a bike trip the floor also has to take whatever you brought inside off the bike, so a few centimetres is not nothing.

Peak height

11cm more headroom in the Alto TR1
Big Agnes Copper Spur HV UL1
97cm
Sea to Summit Alto TR1
108cm

Whether you can sit up, which decides how a rained-out afternoon goes.

Side by side

Including the rows where they are level.

Big Agnes Copper Spur HV UL1Sea to Summit Alto TR1
Folded pole length445mm — too long for drop bars450mm — too long for drop bars
Pole figure sourcePacked bag length, used as a proxyPacked bag length, used as a proxy
Minimum weight964g936g
PitchingFreestandingsemi
Floor area224 × 97cm — 2.16m²215 × 107cm — 2.29m²
Peak height97cm108cm
Price$400$380
Big Agnes
Copper Spur HV UL1
$400 · 936g
Sea to Summit
Alto TR1
$380 · 1050g

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