Gibson Street 12 × 10 Shed · West wall

Your windows,
explained like you’re five

Think of each window as a little picture frame built into the wall. Four pieces of full-depth 2×4 make the strong green frame. The old glass sash sits against that opening. The other wall pieces are thinner and disappear behind the interior plywood.

The short answer: Keep the two vertical window studs, the sill, and the header at the full 3½-inch depth. Rip the ordinary girts and non-window studs to 2¾ inches. After the 0.451-inch interior liner goes on, the four window-frame pieces remain visible by about 0.30 inch—essentially the same reveal as the posts.

First: the six words that keep getting mixed up

SASH

The actual window

The wooden rectangle containing the glass. Yours is 34″ wide × 19⅝″ tall. It is not the framing in the wall.

WINDOW STUDS

The left and right sides

Two vertical 2×4s. Their inside faces establish the opening width. They are also sometimes loosely called jamb studs.

SILL

The bottom

A horizontal 2×4 between the window studs. For this build, its top edge is at 48″.

HEADER

The top

A horizontal 2×4 between the window studs. Its bottom edge is at 67⅝″.

STOPS

The little ledges

Smaller trim pieces that overlap the edge of the sash and keep it from passing through the opening.

CASING

The outside picture frame

Visible 1×4 trim around the opening. It covers cut sheathing, housewrap, flashing edges, and the siding transition.

What you are building

4×4 TOP PLATE — already carries the roof load FULL-DEPTH WINDOW STUD FULL-DEPTH WINDOW STUD HEADER — 34″ LONG SILL — 34″ LONG SASH 34″ × 19⅝″ 34″ clear between inside faces 19⅝″ clear Viewed straight-on. Green = opening frame. Amber = ordinary wall framing.

In this post-and-beam shed, the continuous 4×4 top plate carries the rafters. The piece called the window “header” is therefore mainly the top rail of the window opening—not the kind of large built-up header used over a window in a conventional stud-bearing wall.

Why some 2×4s get ripped and these do not

TOP-DOWN CUTAWAY Outside is at the top · inside is at the bottom EXTERIOR PLYWOOD + WRB + SHINGLES RIPPED GIRT 2¾″ deep WINDOW FRAME 3½″ deep 0.451″ INTERIOR PLYWOOD LINER ~0.30″ proud Hidden behind liner ✓ Visible like the posts ✓
3.500″ full depth − 2.750″ ripped depth − 0.451″ liner = 0.299″ visible reveal

The keep-full / rip-it cheat sheet

PieceFinal depthWhat happens inside
4×4 posts and top plateKeep fullRemain exposed.
Four window studs (two per window)Keep at 3½″Form the visible left and right sides.
Two window sillsKeep at 3½″Form the visible bottoms.
Two window headersKeep at 3½″Form the visible tops.
Ordinary full-height studs elsewhereRip to 2¾″Disappear behind the liner.
Ordinary horizontal girtsRip to 2¾″Disappear behind the liner.
Small infill/cripple pieces, if anyNormally 2¾″Hidden; keep full only if deliberately part of the visible frame.

How the parts relate, in plain English

  1. Build the hole first. Two full-height window studs make the sides. A 34″ sill and a 34″ header fit between them.
  2. The inside faces control the size. The opening is the empty space—not the outside-to-outside size of the lumber.
  3. The sash is the glass-bearing flap. It is hinged at the top and opens outward and upward. It is held against stops/trim rather than behaving like a modern replacement-window unit.
  4. Exterior plywood is cut around the hole. Housewrap and sill/head flashing manage water before the sash and casing conceal the edges.
  5. The interior liner is cut around the full-depth frame. It butts into the sides of the window studs, sill, and header; it does not cover their inside faces.
  6. Trim finishes the job later. Exterior 1×4 casing dresses the opening; smaller window stops locate and retain the sash.

Your two finished openings

Opening size

34″ wide × 19⅝″ high, formed between the inside faces of the four framing pieces.

Vertical placement

Sill top at 48″; header bottom at 67⅝″. The difference is exactly 19⅝″.

Horizontal placement

Both openings have been shifted 3″ toward the center of the west wall to clear the matched corner braces.

Special north stud

The northmost window stud stops at about 71″ where it meets the brace; the brace backs the sheathing above it.

One document conflict resolved here: the current Wall Framing page says both “every stud” gets ripped and “all rough-opening framing” stays full-depth. For this guide, window stud means one of the four sides of a window opening, so it stays full-depth. The mass-ripping instruction applies only to ordinary hidden studs and girts. Label the eight window-frame pieces before the ripping session so none goes through the saw by mistake.

The one-sentence mental model

Green wood makes the visible picture frame; amber wood merely holds up the wall skins; blue is the old glass sash; red trim hides the weatherproofing and keeps the sash where it belongs.

Project-specific guide prepared from the current Wall Framing document and the original Jamaica Cottage Shop plans. As-built measurements beat this page before final cuts.