As a resident of New England where winters are fierce I'm running into a bit of a problem with both casual and even 'proper' modern kilts in that it seems to me that none are as capable as they could be as a cold-weather garment. In fact many casual kilts are wholly unsuitable, being made of cotton or nylon, but even the highest-priced woollen kilts have serious flaws.

As an engineer I'm finding the modern kilt manufacturing techniques may be flawed and far less effective than the traditional kilt-making methods for protecting the wearer against cold. Both casual and 'proper' modern kilts are unsuitable for New England (or indeed Scottish) winters due to the method of their manufacture. I've been doing a bit of research on the kilt with regards to its use as cold-weather clothing. I found some interesting things:

According to what I've read so far, originally the highland kilt was made of thick wool (not the thin wool of the modern kilt) and box-pleated. Box pleats create a very effective double-envelope to hold in an outer and an inner insulating layer of air. Knife pleats (which are the style on many modern kilts) are not as effective at keeping the air warm because they tend not to hold a layer of air in an envelope - in fact the air is forced out as in a concertina effect. If a wind hits the kilt against the pleating the pleat will tend to fall open and only layers of cloth come between the cold blast of air and the wearer's skin - there's no insulation beyond what the cloth itself contains. With a box pleat on the other hand, however the wind hits the kilt EVEN IF THE PLEAT BLOWS OUT, the outside air will tend to hit the kilt on an insulated layer and not directly over the wearer's skin. This affords the wearer a whole lot more protection from cold than does the knife-pleated kilt.

Also, the fact that the pleats on a box-pleated kilt run vertically means that the heat is held in at the top, where you really need it. The box pleat encourages air movement WITHIN the pleat itself and the wearer's movement tends to keep the pleat filled with air. This effectively adds another layer of insulation and keeps warm air at the top of the kilt where it's most needed. A knife pleat cannot do this, as all the air in the pleat is constantly being pushed in and out of the pleat with movement. Instead of keeping warm air at the top of the kilt, this will tend to force any insulating air into the main body of the kilt or out into the air outside, and with a single breeze under the kilt the entire warmth of the garment can be lost. This can't happen with a box-pleated kilt as some air is always kept in the pleats.

It seems to me that the box pleat (which was the traditional manner of pleating the kilt) will keep the wearer warmer. In my opinion, this is why modern kilts will tend to be colder than the traditional kilts. It's also why many kilt-wearers admit that the modern kilt is cold in the harshest conditions. It seems to me that modern kilt-wearers simply haven't experienced the true warmth of a traditional kilt because kilt-making has become a slave to fashion rather than serving the practical purpose that the kilt originally served.

I think that the knife pleat and the reduction in wool weight probably came into fashion when kilts stopped being a practical article of clothing and became a fashion statement. When machine stitching became the way to make clothes, again the box pleat was that much more difficult to make. Then we have the increased length from the traditional 4 or 5 yards to the modern 8 yards - which may be an effort to bring more comfort to the kilt for cold weather - comfort that would be better served with a thicker but lighter box-pleated kilt. The longer kilt adds layers, but not insulation. It also unbalances the kilt, making the rear of the kilt very much heavier.

Just my opinion, but it makes sense to me. If my musings make sense to anyone else, let me know.

Anyway, with the above arguments in mind, can anyone direct me to a few kilt manufacturers who make heavier wool box-pleated kilts. I've found one - Albanach.org, but I'd like to find others for comparison, as I'd like to get myself a good winter kilt so that I can be as comfortable as possible in all weathers.