The Domex Limit

Understanding Your Sleeping Bag’s Performance

A sleeping bag’s primary function is not to generate warmth but to retain the heat your body produces while you sleep. This heat retention is crucial for staying warm in cold conditions. Our temperature ratings reflect how well a sleeping bag can maintain warmth when external temperatures drop to a specified level.

Understanding Temperature Ratings

Sleeping bag warmth is influenced by individual factors such as metabolism, clothing, and sleep habits. Because of this variability, our temperature ratings serve as helpful guidelines rather than absolute measures. At Domex, we use the European EN ISO 23537-1:2002 standard for all our down sleeping bags to ensure reliable performance ratings.

This system provides three key temperature ratings:

  • Comfort – The temperature at which a standard woman can sleep comfortably in a relaxed position. Men typically find the sleeping bag comfortable at lower temperatures than this rating.

  • Lower Limit – The lowest temperature at which a standard man can sleep for eight hours in a curled position without waking. Warm sleepers can use this as an indicator of the bag’s suitability in colder conditions.

  • Extreme – A survival-only rating for a standard woman. Between the Lower Limit and the Extreme rating, discomfort and a strong sensation of cold should be expected, with a risk of hypothermia. This is not a recommended operating temperature but rather an emergency survival limit.

The Domex Limit

In addition to the EN ISO 23537-1:2002 ratings, we have developed the Domex Limit to offer further insight into real-world sleeping bag performance. Unlike the Extreme rating, which indicates survival conditions, the Domex Limit represents a practical, usable temperature range.

This limit is based on our extensive experience, as well as feedback from outdoor enthusiasts and testers. It assumes that the user is prepared with:

  • Thermal underwear (long-sleeve top and leggings)

  • Socks

  • A hat

  • A high-quality down or synthetic puffer jacket

  • A sleeping mat with an R4 or higher rating

By considering both the standardised EN ISO ratings and the Domex Limit, you can make a well-informed decision about which sleeping bag best suits your needs.

Ascent Instructional Videos

  • Ascent 1 - Instructional Video

  • Ascent 2 - Instructional Video

Ascent 1 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub.
  5. Insert the frame tips into the corner grommets, so that the frame is erect, matching pole tips with colour-coded webbing loops and grommets.
  6. Attach the plastic clips of the inner tent to the frame.
  7. Lay the rainfly over the frame then attach the fly to the corners of the inner tent.
  8. Peg out the vestibules until they are taut.
  9. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; an unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.

Ascent 2 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub. Assemble the separate short ridge pole.
  5. Insert the frame tips into the corner grommets so the tent frame is erect. 
  6. Attach the plastic clips of the inner tent to the frame.
  7. Rest the short ridge pole in the divot of the centre clip and attach the ceiling of the inner tent to the corresponding ball clips over the ridge pole. Tension it over the frame.
  8. Lay the rainfly over the frame, attaching the two clips at the fly centre to the ridge pole first then attach the fly to the corners of the inner tent.
  9. Peg out the vestibules until they are taut.
  10. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; an unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.

Velocity Instructional Videos

  • Velocity 1 - Instructional Video

  • Velocity 2 - Instructional Video

Velocity 1 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub. Assemble the separate short ridge pole.
  5. Insert the frame tips into the corner grommets, so that the frame is erect, matching pole tips with colour-coded webbing.
  6. Attach the plastic clips of the inner tent to the frame.
  7. Attach the short ridge pole to the pole socket at the top of the frame and then attach the two remaining roof clips of the inner tent to the ends of the ridge pole with the corresponding ball clips and tension it over the frame.
  8. Lay the rainfly over the frame, attaching the two clips at the fly centre to the ridge pole first. Attach the Velcro tabs to the frame.
  9. Attach the rainfly to the corners of the inner tent, hooking the metal tabs under the poles. Peg out the vestibules until they are taut.
  10. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; an unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.

Velocity 2 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub.  Assemble the separate short ridge pole.
  5. Insert the frame tips into the corner grommets, so that the frame is erect, matching pole tips with colour-coded webbing.
  6. Attach the plastic clips of the inner tent to the frame.
  7. Attach the short ridge pole to the pole socket at the top of the frame and then attach the two remaining roof clips of the inner tent to the ends of the ridge pole with the corresponding ball clips and tension it over the frame.
  8. Lay the rainfly over the frame, attaching the two clips at the fly centre to the ridge pole first. Attach the Velcro tabs to the frame
  9. Attach the rainfly to the corners of the inner tent hooking the metal tabs under the poles and using tension buckles to tighten. Peg out the vestibules until they are taut. 
  10. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; An unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.

Scout Instructional Videos

  • Scout 1 - Instructional Video

  • Scout 2 - Instructional Video

Scout 1 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub.
  5. Insert the frame tips into the corner grommets, so that the frame is erect, matching pole tips with colour-coded webbing.
  6. Attach the plastic clips of the inner tent to the frame.
  7. Lay the rainfly over the frame, attaching it to the ridge pole first then attach the fly to the corners of the inner tent.
  8. Peg out the vestibules until they are taut.
  9. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; an unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.

Scout 2 - Step by step

  1. Remove any sharp debris from the intended campsite.
  2. We recommend using the corresponding tent footprint (sold separately). Lay this out first.
  3. Lay out the inner tent (atop the footprint if using) and peg the corners out taut.
  4. Assemble the tent alloy frame. Make sure the aluminium pole sections are fully engaged in the hub. Assemble the separate short ridge pole.
  5. Insert the frame tips into the corner grommets so the tent frame is erect.  
  6. Attach the plastic clips of the inner tent to the frame.
  7. Rest the short ridge pole in the divot of the centre clip and attach the ceiling of the inner tent to the corresponding ball clips over the ridge pole. Tension it over the frame.
  8. Lay the rainfly over the frame, attaching the two clips at the fly centre to the ridge pole first then attach the fly to the corners of the inner tent.
  9. Peg out the vestibules until they are taut.
  10. Peg out the corner storm ropes for stability in the wind.

USE TIPS: All tents require securing with pegs; an unsecured tent is dangerous and susceptible to damage. Additional pegs and ropes may be required in challenging weather conditions. Adjustment of pegs and ropes may be necessary to maintain tension and optimal weatherproofing.