Install a Prehung Interior Door

A. Finished-Project Specification

Quantity: one installed prehung interior door unit per approved opening, consisting of a plumbed and fastened hinge jamb, a plumbed and fastened strike jamb, a fastened head jamb, consistent head and side reveals, correct floor clearance, and a documented installation record.

B. Component Schedule

Component	Quantity	Material	Finished Size	Preparation
Prehung door unit	1 per opening	Per approved door schedule	Per door schedule (size, jamb width, handing)	Inspected for twist and damage; shipping braces retained until permitted
Hinge-side shims	Per hinge location, pairs	Cedar or composite shim stock	Trimmed flush at each fastening point	Installed in opposing pairs behind each hinge
Strike-side shims	Per specified fastening point, pairs	Cedar or composite shim stock	Trimmed flush at each fastening point	Installed after hinge jamb is fastened and reveal is checked
Head-jamb shims	Per specified fastening point	Cedar or composite shim stock	Trimmed flush at each fastening point	Installed after side jambs are plumbed and fastened

C. Material and Documentation Takeoff

• Prehung door unit: one unit matching the approved door schedule for size, handing, swing, jamb width, wall thickness, and hardware preparation.
• Shims: sufficient cedar or composite shim stock for every specified fastening point at the hinge jamb, strike jamb, and head jamb.
• Fasteners: jamb fasteners identified by the door schedule for hinge, strike, and head-jamb fastening points, plus any longer approved screws for locations specified into framing.
• Documentation: Door Installation Record, rough-opening inspection results, and final clearance and reveal measurements.

D. Fastener and Hardware Schedule

Joint	Fastener/Hardware	Installation Direction	Pilot Hole	Seating Condition
Hinge jamb to framing (first fastener)	Per door schedule	Through jamb and top hinge-area shims into framing	Per door schedule	Snug without bowing the jamb; verify plumb before adding remaining hinge fasteners
Hinge jamb to framing (remaining hinge points)	Per door schedule	Through jamb and shims behind each hinge into framing	Per door schedule	Snug, jamb straight over full height
Strike jamb to framing	Per door schedule	Through jamb and shims at latch and specified points into framing	Per door schedule	Snug, reveal consistent with door closed
Head jamb to framing	Per door schedule	Through jamb and head-jamb shims into framing	Per door schedule	Snug, head reveal consistent across width
Long hinge or strike screws (where specified)	Per door schedule	Through hinge or strike location into framing	Per door schedule	Installed only where specified, without distorting the jamb

Do not treat "jamb fastener" or "long screw" as a complete specification. Use the exact fastener type, length, and location identified by the approved door schedule or door manufacturer's instructions for this unit.

E. Reference Conventions

Hinge jamb: the jamb leg fastened and plumbed first. Strike jamb: the jamb leg adjusted second to produce a consistent reveal. Reference face: the room-side face of the jamb, used for reveal measurement. Finished-floor reference: the single elevation recorded in Project 01, used for floor-clearance measurement at the bottom of the door.

F. Rough-Opening and Unit Verification

1. Verify door size, handing, swing, jamb width, wall thickness, and floor condition against the approved door schedule. Confirm hardware preparation matches the specified latch set before proceeding.
2. Inspect the rough opening for size, plumb, level, square, backing, and floor elevation. Measure opening width and height at multiple points and check diagonals for square.
3. Confirm the opening is free of wiring, plumbing, and protruding fasteners. Correct any conflict before placing the unit.
4. Remove packaging while keeping shipping braces until the manufacturer permits removal. Retain braces that hold the door in the closed position during handling.
5. Inspect the unit for twist, damage, hinge security, and matching components. Sight down each jamb leg for twist and confirm hinge screws are tight.
6. Establish finished-floor clearance using the approved reference. Record the target clearance from the Project 01 finished-floor reference on the Door Installation Record.

G. Placing and Shimming the Hinge Jamb

1. Place the unit in the opening and center it. Confirm equal reveal margins at both side jambs before shimming begins.
2. Shim behind the top hinge location. Install shims from both directions to form a flat surface directly behind the top hinge.
3. Plumb the hinge jamb in both directions. Check plumb with the level held against the jamb face and against the jamb edge.
4. Install the first approved fastener through the jamb or hinge location. Drive the fastener specified by the door schedule at the top hinge shim point only.
5. Shim and fasten behind each remaining hinge. Repeat the shim-and-check sequence at every hinge location down the jamb.
6. Check hinge-jamb straightness with a long level or straightedge. Confirm the jamb is straight over its full height with no bow between hinge points.

H. Reveal Check and Strike-Jamb Fastening

1. Close the door and inspect the head and strike-side reveals. Measure the gap at the head and at multiple points along the strike side.
2. Shim the strike jamb at the latch and other specified points. Install shims in pairs to bring the strike jamb into a position that produces a consistent reveal.
3. Adjust the frame until reveals are consistent and the door remains stationary at partial openings where appropriate. Recheck the door at several partial-open positions.
4. Fasten the strike jamb and head jamb according to the approved method. Drive fasteners at each specified shim point once the reveal is confirmed correct.
5. Install long hinge or strike screws only where specified and without distorting the jamb. Confirm the jamb remains straight after installing any longer screws into framing.

I. Finish Adjustments and Verification

1. Trim shims without damaging the wall. Score each shim with the utility knife at the wall surface and snap or cut it flush.
2. Operate the door repeatedly. Swing the door through its full range at least five times, checking for binding, rubbing, or unintended movement.
3. Check swing, latch alignment, floor clearance, jamb twist, and frame security. Confirm floor clearance against the finished-floor reference and confirm the frame does not move when pressure is applied at each jamb.
4. Stop work if the opening or wall condition prevents safe adjustment. Document the condition and refer it to a qualified professional before continuing.
5. Document final clearances, reveal, and fastening. Record measured reveal, floor clearance, and confirmation of every specified fastener location on the Door Installation Record.