Tips for Sewing with Boiled Wool

It’s that time of year when you are looking for fabrics to work with to transcend the season. Liz Haywood explains why boiled wool is perfect!

Xanthea T-shirt - Zero Waste Sewing Pattern by The Craft of Clothes

What is Boiled Wool

Boiled wool is felted wool. It has some wonderful properties – it’s easy and fast to sew, doesn’t fray and it’s cosy to wear.  It also comes in some fabulous bright colours as well as neutral basics. Most boiled wools are 100% wool but some are wool combined with a small amount of viscose.  Boiled wool comes in a range of thicknesses and some are softer and more pliable than others.

Choosing a pattern

It’s possible to buy patterns which are specifically designed for boiled wool and take advantage of the felted nature of the fabric. Often these are unlined and have raw edges instead of hems. You can also use regular sewing patterns designed for wool. Suitable types of garments include jackets, blazers, coats, cardigans, vests, skirts, capes and hats.

Preparing to sew

Boiled wool is expensive, so it makes sense to get the fit right first with a toile/muslin. Should you pre-wash boiled wool?  Yes – boiled wool can shrink a lot – up to 20%!  Allow for this when you buy the fabric so you have enough. Pre-wash it in the same way you plan to wash the garment, either by hand or delicate wool cycle. Dry flat (a trampoline is great for this!) and steam iron on wool setting.

Seams and hems

As boiled wool doesn’t fray, the seams don’t need neatening and often the hems can be left raw.

The seams can be sewn as regular plain seams, which can be topstitched on each side.  Press the seam open, then topstitch both sides of the seam, either close to the original seam line or 6mm (¼ in) from the seam line for more pronounced topstitching.

Sometimes the seams are sewn as lapped seams. Lapped seams can potentially make the garment reversible since they look the same on both sides. Patterns which are specially designed for boiled wool often have these, or you can adjust the seam allowance to make them lapped. For lapped seams, you’ll need only 6mm (¼in) seam allowances, which are simply lapped to create a 1.2cm (½in )double section and topstitched with one or two rows of stitching. Mark double the seam allowance with chalk or a sliver of soap to help align the lap over.

Another suitable type of seam is slot seam (above), which requires no seam allowance at all. The raw edges are butted together, with a 2.5cm (1in) strip of fabric laid underneath. It’s topstitched in place.

Cutting out

Boiled wool doesn’t have a right or wrong side, so pick the side you want the world to see and mark it so it’s consistent.

You need a very clean-cut edge, because it will show on raw edges and lapped seams, so use a brand-new rotary cutter blade or very sharp scissors. Avoid snipping the notches if you’re making lapped seams and mark them with chalk instead.

Many patterns for boiled wool don’t use interfacing at all. If you do need interfacing, you may find that iron-on fusing won’t stick properly to the wool; in this case, use sew-in.

Washing and caring

Boiled wool, like most woollen fabrics, doesn’t need washing often as it naturally repels dirt and odours.  If you think your garment needs cleaning, first see if you can brush or gently spot-clean away marks. Air it outdoors or put it in the bathroom when you take a shower.  

Enjoy sewing and wearing boiled wool!

Author: Liz Haywood
IG: @lizhaywood3754