Buying Guide
Prehung vs Slab Doors: Which Is Right for Your Project?
Picking between a slab door and a prehung unit is one of the first decisions on any door project. The wrong choice means hours of extra install labor — or worse, a door that never hangs right. This guide walks through what each is, when to use which, what each costs, and the practical install differences. Written for LA and Orange County homeowners and contractors who want a clear answer, not a sales pitch.
What is a slab door?
A slab door is the door panel and nothing else — no jamb, no hinges, no pre-drilled holes. It arrives flat, ready to be hung in an existing frame.
Slab doors come in standard widths (24", 28", 30", 32", 36") and heights (80", 84", 96"). Material varies — solid wood (mahogany, walnut, oak, alder), engineered cores, MDF, fiberglass — but the format is always the same: just the panel.
To install a slab, you need a usable existing jamb. You'll cut out (mortise) the hinges, drill the handle and deadbolt holes, plane the edges to fit the opening, and hang it on the existing hinge plates. It's standard finish-carpentry work — typically 2–3 hours per door for an experienced carpenter.
What is a prehung door?
A prehung door is the door pre-mounted in a complete jamb assembly. Hinges are already mortised and screwed in. Holes for the handle and deadbolt are pre-bored. Strike plate is pre-cut.
The whole unit drops into the rough opening as one piece. You shim it plumb, screw the jamb into the framing, install trim, and you're done. Install time is typically 1–2 hours per door — about half of slab work, with no specialty tools required.
At THE DOORFATHER we build prehung units to your jamb width (4-9/16", 5-1/4", 5-1/2", 6-9/16", or custom) in our LA facility. Hinges in your choice of finish — satin nickel, oil-rubbed bronze, matte black, antique brass. Threshold and weatherstripping for exterior. Door swing handed left or right, in or out. Read more about our prehung service.
When to choose slab
Slab is right when:
- Your existing jamb is in good shape. Replacing a tired-looking door but the frame is solid? Slab is faster to ship (no assembly time) and cheaper.
- You're doing a finish-carpentry job anyway. If a carpenter is on site for trim, baseboard, and casing, hanging a slab is just one more task.
- You want to keep historic jambs. Older homes with custom-milled trim or non-standard openings benefit from preserving the existing frame.
- Budget is tight. Slab is typically $50–$150 cheaper than prehung for the same door.
When to choose prehung
Prehung is right when:
- You're framing a new opening. No existing jamb means you need a complete unit — slab won't help you.
- You want the install done fast and right. Factory-precise hinge mortises and pre-bored handle locations eliminate the most common slab-install problems (door not plumb, handle holes off-center, hinges not aligned).
- You're not a carpenter. A prehung unit can be installed by a handy homeowner. Slab work is finish-carpentry territory and benefits from experience.
- You're doing multiple doors. The time savings compound. A 10-door project might save 10 hours of labor.
- You're buying a custom or specialty door. Hand-carved doors, oversized entries, and iron doors are heavy — getting them hung straight on existing hinges is harder than people expect. Prehung means you only have to align one big assembly, not carefully mortise hinges into delicate carved wood.
Cost comparison
Indicative pricing for an interior door from our catalog:
- Slab door: $250–$1,200 depending on wood species and design
- Prehung interior: +$350 over slab (single, standard jamb width)
- Prehung exterior: +$500–$700 over slab (includes threshold + weatherstripping)
- Custom jamb width: +$0 (4-9/16" included), +$40 for 5-1/4", +$75 for 6-9/16", +$120 for fully custom
- Premium hinges: +$35 for oil-rubbed bronze or matte black, +$45 for antique brass
Add $200–$400 in saved labor for prehung over slab on a typical install, and the prehung often comes out close to even on total project cost — sometimes cheaper.
Install time and tools
Prehung install: level, drill/driver, shims, finish nails, hammer, caulk gun. 1–2 hours per door for an experienced carpenter, 2–4 hours for a confident DIYer.
Slab install: all of the above, plus a router (or sharp chisel) to mortise hinges, a hole saw or door-handle jig to bore the handle and deadbolt holes, a hand plane or belt sander to fit the door edges. 2–4 hours per door for an experienced carpenter; not typically a DIY job.
If you're hiring an installer, ask whether their bid is for slab or prehung work. Most LA-area contractors charge similar hourly rates either way, but the prehung will be done in less time and with fewer call-backs to fix alignment.
What we recommend
For most replacement projects with intact jambs: slab with installation by a finish carpenter. Cheaper, faster shipping, preserves the frame.
For new construction, multi-door projects, custom orders, or anyone uncomfortable with finish carpentry: prehung. Higher upfront cost, lower total cost when you factor labor.
For specialty doors (iron, hand-carved, oversized): prehung, no exceptions. The doors are too heavy and too valuable to risk hanging on existing hinges that may not be load-rated.
Need help deciding for a specific project? Call (424) 466-7707 with your rough opening dimensions and what you're hanging. We'll tell you what makes sense.
Frequently asked questions
Can a slab door be converted to prehung later?
Not really. Once you've installed a slab in an existing jamb, you can't extract that combination and re-sell it as a prehung. If you might want a prehung-style fit eventually, order prehung from the start.
Are prehung doors interior or exterior only?
Both. Interior prehung uses a flat threshold (or no threshold). Exterior prehung includes an adjustable threshold (oak, aluminum, or marble) and weatherstripping (standard or premium Q-Lon). Configure during ordering.
How do I know my jamb width?
Measure the depth of your wall from drywall surface to drywall surface (or trim line to trim line). Standard 2x4 wall = 4-9/16" jamb. 2x6 wall = 6-9/16". If you have extra drywall layers or thick plaster, you may need 5-1/4" or 5-1/2".
Can THE DOORFATHER prehung a door I bring you?
Yes. Bring or ship the slab to our San Dimas warehouse. We charge for the jamb, hinges, hardware, and assembly only — typically $300–$500 depending on complexity. Call (424) 466-7707 for a quote.
Have a project to talk through?
Whatever you're working on, the fastest path is a phone call. We'll point you at the right doors — or build you something custom if nothing in the catalog fits.
(424) 466-7707 info@thedoorfather.com