Panel Doors

A panel door is a frame with one or more panels set into it. It consists of a frame with one or more recessed, raised, or flat panels. The frame is built from vertical stiles and horizontal rails, with the panels fit between them. That construction matters more than most people think. Building a door from several joined pieces instead of one slab gives it room to move — which is exactly what you want in a climate that swings from -20°F in January to 80°F in July. The pieces shift; the door stays flat.

Panel count drives the look. Panels range from 1 to 6; 6-panel doors are traditional and formal, while 2-panel shaker or raised styles are versatile choices for transitional and modern homes. A 6-panel reads Colonial. A clean 2-panel shaker reads modern or transitional. Pick the profile that matches the house, not the trend.

Panel doors differ from flush doors, which have a flat, uninterrupted face with no visible framing. Both have their place. The real decision isn’t the face — it’s what’s behind it.

Core Construction Is the Decision That Matters

Three core types, three jobs. This is where the money and the performance live.

Solid wood is the heaviest and most durable, with the best sound control. Put it where it shows and where it gets used — high-visibility entries and rooms that take abuse.

Solid core runs an engineered wood interior under a veneer or primed surface. It’s the balance pick — decent weight, good sound dampening, reasonable cost. Choose solid core doors for bedrooms and offices to improve sound control and durability. Bedrooms, baths, home offices — anywhere you want a door to feel solid and keep noise on its own side of the wall.

Hollow core is a lightweight cardboard honeycomb interior. It’s the budget option and the easiest to hang. Use hollow core for budget-friendly, low-traffic areas like closets.

Commercial spec writers go further. One institutional standard requires that interior wooden doors be solid core with adhesives that are 100% waterproof, hollow core doors not be specified, and all doors be solid core flush with veneer faces, commercial heavy duty minimum grade, 1-3/4” thick. That same standard sets an acoustic floor: where doors are used as part of an acoustical barrier assembly, they shall be rated a minimum of STC 33. If sound control is the goal, that STC number tells the real story — not the panel style.

Core type	Weight	Sound control	Best for
Solid wood	Heaviest	Best	High-visibility entries, high-use rooms
Solid core	Medium	Good	Bedrooms, baths, offices
Hollow core	Lightest	Minimal	Closets, low-traffic areas

Sizing and Matching the Door to the Room

Standard interior height is 6’8”. Standard heights are 6’8”, but 8’0” doors are increasingly popular for high-ceiling rooms. If you’ve got the ceilings for it — and plenty of newer builds in the valley do — the taller door changes the whole proportion of a room.

Match the door to what the room asks for. Solid panels handle privacy and sound for bedrooms and baths. Glass panels bring light into offices and pantries. Louvered or hollow-core suits closets and utility spaces. Profile follows the architecture: raised 4- or 6-panel for traditional and Colonial work, flat panel or shaker for modern, shaker for transitional.

Western Building Center stocks a 2-8 Colonist prehung in both left-hand and right-hand swings — a classic panel profile in a workhorse 2’8” width.

Prehung vs. Slab, and Getting the Install Right

Two formats. Prehung is the door already hung in its frame — buy it for new construction or when you’re replacing the whole assembly, because the alignment is handled at the factory. A slab is just the door, for dropping into an existing frame that’s still square and sound.

Measuring is where jobs go sideways. Measure width at the top, middle, and bottom, then use the smallest number. Walls move; openings aren’t always square, especially in older houses that have settled.

Size for clearance, not for a tight squeeze. The door should be approximately 1/2” less in both width and height than the opening. And the rule that never changes: the door must be installed plumb, level and square. Get the frame right and everything else — latching, sealing, swing — falls into place. Force a crooked frame and you’ll fight that door for years.

A couple of install cautions worth carrying to the jobsite. When insulating between the unit frame and the rough opening, do not overpack batt insulation or overfill with foam — bowed jambs will result, affecting product performance and proper operation of the unit. Easy mistake. Spray too much expanding foam, the jamb bows, the door binds. Shim it, don’t pack it.

Frequently Asked Questions

What’s the difference between a panel door and a flush door? A panel door has a visible frame — stiles and rails — with one or more recessed, raised, or flat panels set inside it. A flush door has a flat, uninterrupted surface with no visible framing. Panel doors give you style options; flush doors give you a clean, plain face.

Why does panel construction resist warping? Building a door from several joined pieces rather than one solid slab gives the wood room to move as temperature and humidity change. That’s a real advantage where seasonal swings are wide — the individual pieces shift slightly while the door stays flat.

Which core should go on a bedroom or office door? Solid core. It’s an engineered wood interior under a veneer or primed surface, and it improves both sound control and durability over hollow core — without the weight and cost of solid wood. For rooms where you want quiet and a solid feel, it’s the balance pick.

Prehung or slab — which do I need? Prehung for new construction or a full replacement, because the door comes already hung in its frame and the factory handled the alignment. Slab when you’re swapping a door into an existing frame that’s still square and in good shape.

How do I measure for a replacement door? Measure the width at the top, middle, and bottom, then use the smallest dimension. Plan for the door to be roughly 1/2” less than the opening in both width and height so it has clearance to operate.

What’s STC and why does it matter? STC is a sound-control rating. In commercial work, doors used as part of an acoustical barrier are required to hit a minimum of STC 33. For interior doors, that rating matters more than the panel style if keeping noise contained is the goal.

Does Low-E glass help on exterior panel doors? Yes. High-performance Low-E insulating glass lowers energy costs, helps homes stay cooler in the summer and warmer in the winter, and reduces the fading of interior furnishings and condensation. In a cold climate, that condensation reduction alone is worth the upgrade on a glazed entry door.