16×20 A-Frame Cabin Plans

About This Design

Sixteen feet is the threshold. Below it a roof-to-deck A-frame pinches the floor to a corridor before it reaches standing height. At sixteen it works — barely, but genuinely — which makes this the smallest true classic in the catalog and the cheapest way to build the shape everybody actually pictures.

The numbers behind that: the roof planes leave about eight and a half feet of floor at six-foot-eight of headroom, and the entry door sits dead on the centreline, 36 inches wide and a full 80 tall, under the peak where the headroom is. The ridge post lands on an engineered header over it rather than beside it, which is what lets a narrow classic carry a full-size door at all.

There is no loft here. Three hundred and twenty square feet on one level, an uninterrupted A from deck to peak, and nothing above you but the ridge.

Key Features

• True roof-to-deck A-frame — no knee walls, no side walls
• The smallest width that makes a true classic
• Full-height 36×80 entry centred under the peak
• 320 sq ft on a single open level
• About 8½ ft of floor at full standing headroom
• Ridge beam, entry header and posts sized PRELIMINARY against the site loads
• Full rafter, ridge, post and bearing framing in the drawings

Build Notes

Read the load path before you cut anything, because it is not the one most A-frame articles describe. A bolted heel joint cannot make its required end distance in a tie this shallow, so these plans do NOT rely on the floor frame acting as a rafter tie. The rafters land on a structural ridge beam, and that beam delivers its load through a built-up post at each gable end to bearing below.

The entry sits on the centreline, under the peak, so the front post lands on an engineered LVL header over the door and a jack pack each side carries it down. Once a jurisdiction is set, the engine sizes that whole chain — beam, header, jambs, post, and the transfer beam or slab pad under it — against the pinned site loads and prints each member with its utilisation ratio. Every one of those sizes is PRELIMINARY: a registered design professional confirms them, and the set says so on every sheet until one does.

Build the deck dead square first: the rafters reference off it directly and there is no top plate to correct an error with. Set the beam and its posts, then bring the rafter pairs up from both gable ends toward the middle.

Best For

A one-room cabin where the roof is the architecture — a weekend place, a studio, a guest cabin at the back of a lot. Three hundred and twenty square feet is enough for a bed at one end, a stove and a small kitchen at the other, and the full height of the ridge overhead in between. It is also the size that still fits on a modest lot and inside a modest budget while reading unmistakably as an A-frame from the road.