Why we use vapor barrier liner in our quilts?

In this post I will talk about the following:

1. What is the problem I am trying to solve
2. What is a vapor barrier
3. What are the advantages of vapor barrier liner
4. What are the common issues vbl and vb clothing and how I address them

Ready to dive in? Let’s begin.

What is the problem I am trying to solve?

The problem is that sleeping bags get cold and wet because of internal condensation when hiking/camping in bad weather (i.e., wet and cold conditions).

This moisture which comes from your sweat and wet clothes compromises the thermal efficiency of the sleeping bag and can result in you feeling cold and may be getting sick.

Examples of possible conditions prone to condensation:

• sleeping in the open under the stars
• sleeping in a tent while its rain or snowing
• very cold conditions
• using single wall tent in windless conditions

What is a vapor barrier?

Vapor barrier liner is a non-breathable material that keeps internal moisture off your insulation – keeping you dry, warm and comfortable in bad weather.

What are the advantages of vapor barrier liner?

Vapor barrier liner bags and clothing are used by polar explorers, as well as long-distance hikers in winters. It protects the bags from frost and condensation, a life-threatening situation in cold, remote conditions.

I have extended the application of vapor barrier to 3 season by integrating a vapor barrier inner in a quilt design along with breathable draft stoppers and zippered foot box.

• DRY Prevents your bag from getting damp due to condensation
• WARMTH Vapor barrier adds 10-15F warmth at no additional weight by minimizing conductive, convective and evaporative heat loss.
• WINDPROOF Without vapor barrier, your quilt / bag needs highly air permeable shell which is not very windproof. This means you need to carry a bivvy if sleeping in the open. Blue Bolt vapor barrier quilts use a windproof shell and breathable draft stopper, so you can skip the bivvy in good weather.
• NO CLAMMINESS Unlike vapor barrier clothing or liner bags, the moisture in vapor barrier quilts can still breath out through the breathable draft stopper thus preventing that uncomfortable clammy feeling.
• LAYERING With vapor barrier quilts you can layer clothing inside the quilt.

Solving the common issues of vb liners and vb clothing

Problem 1 – Clammy feeling

The problem with vapor barrier liner bags and clothing is that it can feel clammy, so most hikers avoid it unless it’s critical such as if they are hiking long distance in remote areas.

Problem 2 – Layering issue

Layering inside a vapor barrier liner bag is not possible as all the layers will get soaked from sweat.

I solved both these issues by integrating vapor barrier liner and breathable draft stopper in the quilt design which allowed the moisture inside to breath out through the draft stopper. This quilt has been tested 3000 km /120 passes in Indian Himalayas by Peter Van Geit and he found no condensation or clamminess issues.

Next, I have also incorporated a zippered foot box which can be opened completely in warmer weather.

Do you find the concept intriguing? Or hard to believe? I would like to offer you an opportunity to field test the quilt. Your purchase will come with a 60 days risk-free trial period. You can return the quilt back for a full refund if it doesn’t work for you..

P.S. I can customize a quilt with a breathable liner by request.