Carvel construction is the frame-first method: set up the keel, stem and transom, erect pre-shaped frames at regular intervals, plank from the bottom up with each plank bent tight against the frame and its neighbour, fasten the planks to the frames with nails or screws, and caulk the seams. For a 4.5 m hull with 16 to 24 frames and 8 planks a side that is 256 to 384 plank-to-frame crossings, so 256 to 768 fasteners at one or two per crossing.
Part of Canoe & Rowing Boat Construction
Carvel is the Mediterranean and later European tradition of laying hull planks edge to edge over a pre-built frame, giving a smooth outside.
The Frame Decides The Shape, So The Precision Moves Earlier
In carvel the hull’s shape is fixed before the first plank goes on: the frames are made to plans or from a mould and set up on the keel. The carrier lists the advantages as a smooth hull with less water resistance, easy plank replacement without disturbing neighbours, and good scaling up, since almost all large ships are carvel. The price is precision: planks must be bent tight to the frame and to their neighbours, and the seams between them are not self-sealing, so they must be caulked.
The effort moves from fitting laps to making planks that lie edge to edge. The planks are bevelled so that the seam is tight on the inside and a little open on the outside, where the caulking goes.
What You Need
- Backbone, plans or moulds, and frames made in advance (see Ribs & Frames)
- Planks straight-grained, edges planed square or bevelled
- Steaming gear for the planks nearest the stems
- Nails or screws long enough to bite well into the frames
- Caulking materials (see Caulking Materials)
Method: Frame, Plank, Fasten, Caulk
Step 1: Set up the frame. Position the keel, attach stem and transom, and erect the pre-shaped frames at regular intervals; brace them and check they are square and plumb.
Step 2: Plank from the bottom up. Bend each plank to fit tightly against the frame and its neighbour, working both sides to keep the hull symmetrical.
Step 3: Fasten the planks to the frames with nails or screws; use one fastener per plank crossing at least, and two on wide planks.
Step 4: Plane the outside fair once all planks are on.
Step 5: Caulk the seams and pitch over them (see Caulking & Waterproofing).
Worked Example: How Many Fasteners?
The ribs-and-frames estimate gives 16 to 24 frames for a 4.5 m hull. With 8 planks a side (16 in all), each frame meets every plank, giving 16 × 16 = 256 crossings at the low end and 24 × 16 = 384 at the high end. At one nail or screw per crossing that is 256 to 384 fasteners; at two it is 512 to 768. Compare this with the clinker count of 630 to 790 rivets in Clinker (Lapstrake): the totals are similar, but carvel adds roughly 63 m of seam to caulk (14 seams of 4.5 m) where clinker adds none.
Common Mistakes
- Planking with frames that are not square to the keel — the planks spiral and cannot be pulled tight.
- Fastening before the plank is fully seated — the plank twists as you drive.
- Planks too wide at the bilge — wide boards do not bend to the curve; use narrower ones where the hull curves most.
- Forgetting the seam gap — a tight outside seam cannot take caulking.
Safety
Bracing and falling frames
Until the planking ties them together the frames are only loosely connected and a large hull can topple while you plank one side. Brace it from both sides and plank alternately; never lean a ladder against an unplanked frame.
What’s Next
- Learn next: Caulking & Waterproofing — sealing the seams
- Combine with: Clinker vs Carvel Construction — whether this is the right method