Single-Breasted 3-Button Blazer with Notched Lapel, Chest Welt Pocket & Three Double-Welt Pockets with Flaps
A classic single-breasted three-button blazer with notched lapels, a chest welt pocket and three flap pockets, including a ticket pocket in the British tailoring tradition. Made in ivory linen or cotton it becomes a summer or wedding jacket; in navy or grey wool it is a timeless everyday blazer.
When To Wear
This tailored jacket is a versatile essential, making it perfect for:
- Business Wear: a refined companion to dress shirts and trousers for professional settings.
- Special Occasions: Ideal for weddings, evening events, or formal gatherings.
- Smart Casual: Dress down with denim or chinos for an effortless, modern look.
Key Design Features
Silhouette: Structured, single-breasted jacket with shaping seams for a tailored fit.
Collar & Lapels: Notched lapel collar with clean lines and refined proportions.
Front: Three-button closure with two lower flap pockets and a double welt chest pocket.
Back: Center-back seam with vent for ease of movement.
Sleeves: Two-piece tailored sleeves with button cuffs.
Details: Double flap pocket design adds structure and classic style.
Level Of Difficulty
Advanced. Requires precision in setting sleeves, constructing tailored lapels, and applying professional finishing techniques with interfacing and lining.
Fabric Recommendations
Wool or wool-blend suiting fabrics, or medium-weight tailored fabrics with structure and drape:
- Worsted wool suiting
- Wool blend gabardine
- Twill suiting fabrics
- Blended tailoring cloths
Additional Supplies
- Lining fabric
- Non-woven material
- Fusible interfacing
- Synthetic padding
- 3 medium buttons (20 mm)
- 9 small buttons (15 mm)
- Shoulder pads
Cutter’s Must
From Main Fabric:
- Back – 2 pieces
- Front – 2 pieces
- Side – 2 pieces
- Center Front Facing – 2 pieces
- Upper Sleeve – 2 pieces
- Lower Sleeve – 2 pieces
- Upper Collar – 1 piece
- Stand Collar for Upper Collar – 1 piece
- Chest Pocket Welt (marked on pattern as “Pocket Off-Set Welt”) – 1 piece
- Pocket Bag (for chest welt pocket) - 1 piece
- Pocket Flap – 2 pieces
- Pocket Welt – rectangle 18 × 3 cm – 4 pieces
- Big Pocket Bag - 1 piece
- Pocket Flap (for right small pocket) – 1 piece
- Right Pocket Welt – rectangle 13 × 3 cm – 2 pieces
- Pocket Bag (for right small pocket) - 1 piece
From Nonwoven Fabric:
Lower Collar (with integrated collar stand) – 1 piece
From Lining Fabric:
For drafting the lining pattern pieces, use the following patterns with the following modifications:
- Back Lining – use Back pattern, add 2 cm ease pleat at center back, excluding vent extension; cut 2.
- Front Lining – use Front pattern excluding center front facing area; cut 2.
- Upper Sleeve - use Upper Sleeve pattern excluding vent extension; cut 2.
- Lower Sleeve - use Lower Sleeve pattern excluding vent extension; cut 2.
- Pocket Flap - cut 2.
- Big Pocket Bag - use Big Pocket Bag pattern, cut 1.
- Pocket Flap (for right small pocket) - use Pocket Flap pattern, cut 1.
- Pocket Bag (for right small pocket) - use Pocket Bag pattern, cut 1.
- Shorten both jacket and sleeve linings by 2 cm at hem.
From Fusible Interfacing:
For drafting fusible interfacing pattern pieces, use the following patterns:
- Front – 2 pieces
- Center Front Facing – 2 pieces
- Upper Collar - 1 piece
- Stand Collar - 1 piece
- Pocket Flap – 3 pieces
- Chest Welt - 1 piece
- Hem allowances of Fronts, Back and Sleeves (copy their width and length and cut)
- Vent extensions of the left Back Part and sleeves (copy their width and length and cut).
Important Information
Before cutting your fabric:
- Print and lay out pattern pieces to determine yardage.
- Check mirrored pieces, notches, and grainlines.
- For patterned fabrics, align carefully for symmetry.
Assembly Instructions
Preparation
Fuse Interfacing
From the wrong side, apply fusible interfacing to the Fronts, Center Front Facings, Upper Collars, Stand Collar, Pocket Flaps, Chest Welt, hem allowances of the body and sleeves and vent extensions of the left Back and sleeves.
Body Shaping
Slash the pocket opening on the front piece, stitch the dart, cut along the fold, and press it open. Baste along the pocket opening edges.
Pocket Flaps
With right sides together, stitch each Pocket Flap to its lining, turn right side out, and press.
Chest Welt Pocket
On the left Front construct a single-welt breast pocket:
- Fold the Welt lengthwise right sides together and stitch across the short ends. Turn right side out and press.
- Pin the Welt (turned downward) to the garment front along the marked placement line.
- Place the pocket bag of lining fabric over the Welt, then pin the pocket bag of main fabric turned upward above it. Stitch 5 mm on either side of the marked line.
- Slash the opening between the stitching lines, clipping diagonally into the corners. Turn the pocket bags to the inside.
- Secure the free edge of the Welt to the pocket bag with zigzag stitches.
- Align both pocket bags and stitch around the contour.
- From the right side, secure the Welt ends to the garment.
Body Shaping
Stitch the front panel seam. Press allowances open.
Hip Pockets
Double-Welt Pockets with Flaps
- Press the welts lengthwise, wrong sides together.
- Pin welts to the Front along the placement lines, one facing upward and one downward.
- Place the pocket bag of lining fabric on the lower welt; place the main pocket bag on the upper welt with the flap inserted face up between the upper welt and the main pocket bag.
- Stitch 5 mm on each side of the markings.
- Cut the pocket opening through the center between stitching lines, clipping diagonally into the corners.
- Turn pocket bags to the inside and fold welts to form 1 cm.
- Serge-stitch the free edges of the welts to the pocket bags.
- Align pocket bags and stitch around the perimeter.
- From the wrong side, stitch the welt ends to the triangular seam allowances.
Main Assembly
Join center back seam to the top of the vent.
Join side seams and shoulder seams; press allowances open.
Vent
- Turn the left vent facing to the right side along the hem allowance; stitch along the hem foldline and turn right side out.
- Turn the hem allowance of the right back to the right side along the vent facing edge; stitch and turn.
- Lay the vent to the left side and secure at the upper edge with a diagonal reinforcement stitch.
Collar
- Join the Stand Collar to the Upper Collar; press allowances open.
- Steam-shape the Lower Collar cut from non-woven fabric over a damp press cloth to set the identical to Upper Collar shape.
- Place the upper edge of the Lower Collar wrong side to the right side of the Upper Collar and stitch with a fine zigzag.
- With right sides together, sew the Upper and Lower Collars along the ends. Turn right side out and press.
Facings
- Join the Center Front Facings to the Upper Collar; press seam allowances upward.
- With right sides together, place the Center Front Facing + Upper Collar unit over the coat body, align edges, and stitch around the front edges and collar.
- Turn right side out and press.
Sleeves
Two-Piece Sleeve with Vent
- Stitch upper and lower sleeve together to the vent notch, easing the upper sleeve as required; press allowances open.
- Turn sleeve right side out.
- Turn the vent seam allowances and sleeve hem to the right side, stitch the vent corner diagonally, trim excess within 1 cm of the seam, and press allowances open.
- Turn hem and vent allowances to the inside, hand-stitch with a cross-stitch, and form the vent overlap.
Sleeve Cap
- Ease-stitch between sleeve cap notches and pull threads to fit the armhole. Steam-shrink the fullness at the cap.
- Join the sleeve seam and press open.
- Set sleeves into the armholes, stitching from the sleeve side.
- Divide sleeve-head wadding (if used) and hand-stitch along the sleeve caps.
Hems
Turn up hem allowances and hand-stitch invisibly.
Sew in shoulder pads.
Lining
- Form a movement pleat at the center back and secure it below the neckline and several centimeters above the hem.
- Assemble the lining pieces in the same sequence as the main garment, leaving about a 20 cm opening along one sleeve seam for turning.
- Insert the lining into the main garment, right sides together, aligning center back and shoulder seams.
Stitch the lining to the Center Front Facings and neckline edges. - Press the open edge of the Upper Collar to the inside.
- Place the Upper and Lower Collars wrong sides together; hand-stitch the Lower Collar to the Upper Collar and the back neckline using a loose zigzag stitch.
- Form a small ease (jump) pleat along the hem and attach the lining to the hem allowance, stitching the lining to the fold of the right back vent facing and to the edge of the left back vent facing (make a small horizontal snip at the base of the left back vent in the lining before attaching).
- Turn the garment right side out through the sleeve opening and close the opening with a neat machine or hand stitch.
Finishing
- Work buttonholes on the left Front and sew buttons on the right Front.
- Work one decorative buttonhole on the left lapel.
- Work non-cut decorative buttonholes on sleeves and secure with buttons.
