Window Trim & Casing for New Construction
Wood jambs and casing added to every window and patio door your builder wrapped in drywall — installed after closing, before or after you move in, by a licensed Minnesota contractor.
Reply within one business day. Or call / text 763-250-3621.
New construction window trim means wood jamb extensions into each drywall-return opening, casing around it, and a stool and apron if you want the traditional look. JMB Builders installs it in homes across the Twin Cities metro, paint-grade or stain-grade to match your doors, left filled, caulked and primed, or painted as its own line. Priced per opening, windows and patio doors alike, so you know the whole-house number before we start. Reply within one business day.
- Priced per opening, windows and patio doors
- Jamb extensions, casing, stool and apron
- Primed and caulked; painting is its own line
Most production builders in the Twin Cities finish windows with drywall returns: the drywall wraps into the window opening and meets the frame with a bead of caulk. It's fast and cheap, which is why they do it. It also cracks at the corners, chips when a blind bracket goes in, and leaves the whole house looking unfinished. JMB Builders adds real wood trim to new-construction windows and patio doors across the metro — jamb extensions into the opening, casing around it, and a stool and apron if you want the traditional look.
A typical job: a buyer in a new home wants wood trim on every window and the patio door before move-in. We install paint-grade wood jambs into each opening, case around them in a profile that matches the door casing, and leave it primed and caulked, with painting quoted as a separate line — or paint it yourself. We price it per opening, so you know the number for the whole house before we start.
Get a written quote for this job
Three photos and a sentence is enough: a reply within one business day, or ask for a free in-home estimate. Or text the photos to 763-250-3621.
What you supply
- Picture-frame or stool-and-apron, and paint-grade or stain-grade (we match your door casing unless you say otherwise)
- Your paint or stain color, if we are finishing it
- A window and patio door count, plus a photo of a typical window and of your door casing
What JMB supplies
- Jamb extension stock, casing, stool and apron in primed MDF, finger-jointed pine or stain-grade wood
- Cutting back and squaring any drywall return that sits proud of the window frame
- Shims, finish nails, glue at the miters, filler and paintable caulk
- Floor protection and daily cleanup when the house is occupied
- Haul-away of cutoffs and packaging
- Photos of the finished windows in your job folder
- Painting or staining when you want it done, quoted as its own line
How it is priced: per opening
Quoted in writing from your photos, with a reply within one business day. What moves the number:
- Number of openings — windows, patio doors, and any mulled or multi-unit windows counted as larger openings
- Picture-frame vs. stool-and-apron (the stool takes more fitting and material)
- Paint-grade vs. stain-grade material and casing profile width
- Jamb depth — deeper 2x6 walls and any openings where the drywall return has to be cut back or squared up
- Finish scope — primed and caulked only, or painted or stained by us as its own line
Send one photo of a typical window, one of your door casing, and a count of windows and patio doors by room. Note any mulled or extra-wide units and the wall depth if you know it.
How long it takes
Most new homes: one to three days for every window and patio door, depending on the count and whether stools are included. Add time if we are painting it, quoted as its own line.
How your project works
- 1
Send photos, get a written quote
Send three photos of the space and a sentence about what you want. You get a clear, itemized reply within one business day. Prefer a look in person? A free in-home estimate is always an option.
- 2
Pick materials, or bring your own
We help you choose profiles and materials that fit the house and the budget, or match your existing millwork exactly — or you buy the door or trim yourself and we install it. Everything is confirmed before the crew is scheduled.
- 3
Clean, precise installation
The crew shows up on time, protects floors and furniture, and installs with tight joints and consistent reveals. Photos of the finished work go in your job folder.
- 4
Walkthrough and invoice
We walk the finished work with you. If anything is not right, we fix it before we call the job done. Then one invoice, paid by check or direct deposit — no card fees, no payment links.
Situations and options
Picture-frame casing
Casing on all four sides with mitered corners. Clean and modern, and the most common choice in newer homes. Works with the drywall sill left in place or with a wood jamb on the bottom.
Stool-and-apron
A wood sill (stool) that extends past the casing with an apron underneath, and casing on the sides and top. The traditional look, and the right call if you want a ledge for plants or a spot to set a coffee cup.
Paint-grade white
Primed MDF or finger-jointed pine jambs and casing. Stable, smooth, and ready for whatever trim color the rest of the house is painted. This is what most new-construction buyers choose.
Stain-grade to match doors
Solid oak, maple, poplar, or pine jambs and casing stained to match stained interior doors or cabinetry. More material cost and tighter joinery, but it ties the whole house together.
Window Trim & Casing for New Construction: questions, answered
Can you trim windows that have drywall returns?
Yes. This is the whole point of the service. We install wood jamb extensions into the opening, flush with the finished drywall, then case around them. Where the drywall return is out of square or bulges past the frame, we cut it back so the jamb sits straight. The finished window looks like it was trimmed by the builder from the start, only better.
Do you do just a few windows or the whole house?
Either. Some homeowners do the main floor first and the bedrooms later; some do everything in one visit. Whole-house packages get the best per-opening price because we're set up once and cutting all the material in a single run. We quote every opening individually either way, so you can pick the scope that fits your budget.
Should we do this before move-in or after?
Before move-in is easiest — empty rooms, no furniture to move, and paint can go on right after us. But we do plenty of these jobs in occupied homes too. We work room by room, protect the floors, and clean up before we leave each day. If you're closing soon, reach out now and we'll get you on the schedule for the week after closing.
Will the trim match my interior doors?
That's the goal. We match the casing profile on your doors so windows and doors read as one set — same width, same style, same reveal. If your builder used a plain flat casing, we can match it or upgrade both doors and windows to a nicer profile as part of the same project.
What is the difference between a jamb extension and casing?
The jamb extension is the flat wood that lines the inside of the opening, from the window frame out to the face of the drywall. It replaces the drywall return. The casing is the molding that sits on the wall around the opening and covers the joint between the jamb and the drywall. A stool is the wood sill at the bottom, and the apron is the piece of casing under it. In a new home with drywall returns, you need the jamb extensions first; the casing goes on after.
Recent JMB work, from our job log
59 installs recorded across 30 Twin Cities communities since Dec 2025. Window and door installs for homeowners and the builders we work with. Counts come straight from our job log; no customer names.
Related jobs we do
Baseboard & Casing Installation
Straight lines, tight miters, and coped inside corners — baseboard and window & door casing installed room by room or across your whole home.
Read moreCrown Molding Installation
Crisp corners, seamless joints, and profiles that fit your home — crown molding installed by a licensed Minnesota contractor who treats trim as a craft, not an afterthought.
Read moreLabor-Only Door Installation — We Install the Door You Bought
You buy the door, we install it right — entry doors, house-to-garage doors, and interior doors hung plumb, sealed tight, and trimmed out by a licensed Minnesota contractor.
Read moreBoard-and-Batten Wall Installation
Even batten spacing, level cap rails, and layouts that land clean around outlets and windows — board-and-batten walls built to fit your room, not a template.
Read moreAttic Hatch Trim — Casing, Painted Panel and Insulated Lid
The scuttle hole with a raw drywall edge and a loose square of drywall dropped on top of it: we case it, build a real lid, seal it and insulate it.
Read moreAttic Ladder Installation — Pull-Down Stairs, New or Replacement
A hallway scuttle hole you need a stepladder for, or an old attic ladder that groans every time it opens — we frame the opening, set the new unit level and case it so it looks like part of the ceiling.
Read morePage reviewed October 1, 2026 · JMB Builders LLC, MN license BC809005 · All finish carpentry pages
Where we work
Finish & Trim Carpentry near you
Based in Zimmerman, scheduling across the Twin Cities metro. Closest first: