Apartment Window Exterior Capping — Aluminum Wrap, Whole Building
The wood trim outside every window on the building is peeling again and the painters are due back.
Reply within one business day. Or call / text 763-204-2099.
Apartment window exterior capping covers the wood brickmould, frame edge and sill outside every window on the building with aluminum coil bent on a brake, so the trim stops needing paint. JMB Builders caps low-rise apartment buildings across the Twin Cities metro and north to St. Cloud: soft wood replaced first, one coil color building-wide, each opening its own line. Priced per opening; send photos for a reply within one business day, or book a free in-home estimate and walkthrough.
- Priced per opening, one line per window
- One coil color across the whole building
- Soft wood replaced before the wrap
On a two- or three-story apartment building, the outside window trim is a maintenance line that never closes: brickmould, the frame edge and the sill get scraped and painted, then peel again at the bottom corners. Capping covers that wood with aluminum coil bent to fit each piece, in a color matched to the windows or the building trim. The wood stays underneath; what the weather hits is the aluminum.
Capping done badly traps water. A wrap bent tight over soft wood hides the rot until it shows up as a stain inside a unit, and a sill cap caulked shut at the bottom holds water against the frame. We probe every opening first, replace soft wood, bend a drip at the head, lap each piece so water sheds down and out, and leave the sill cap able to drain.
The quote lists every opening by elevation, floor and unit, with the wood repair it needs. Cap the whole building, one elevation this year, or only the street side. Upper-floor access is its own line. Before we bid a building of five or more units, we check the city's contractor licensing and permit rules for that building. A certificate of insurance and a W-9 are available on request.
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 763-204-2099.
What you supply
- Building address, unit count and a photo of each elevation
- The coil color, or the window color you want it matched to
- Parking for a trailer and the brake, and a spot to stage coil
- Notice to residents that crews will work outside their windows
- Which balconies or patios need to be cleared, and which elevation goes first
What JMB supplies
- A walk of every elevation, each opening probed for rot and measured
- A line-item quote by opening, grouped by elevation and floor
- Prefinished aluminum trim coil bent on site to each piece
- Soft brickmould, sill nosing or frame edge replaced before capping
- A drip at the head, lapped joints and color-matched sealant
- Upper-floor access listed as its own line on the quote
- Daily clean-up of coil scraps and old sealant
- Photos of each finished elevation in your job folder
- Certificate of insurance and W-9 on request
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; the brake setup is the same for ten windows or a hundred
- What gets capped: brickmould only, or brickmould, frame edge and sill
- Soft wood that has to be replaced before the cap goes on
- Floor height and how the upper windows are reached
- Brick, stucco or lap siding at the trim edge, which changes how the cap is finished
- Stock coil color vs. a color matched to existing windows
- Whole building at once vs. one elevation per season
Send one photo per elevation, a close-up of a typical window outside, and the unit count. A free in-home estimate and walkthrough firms up the opening count and the rot.
How long it takes
Capping runs elevation by elevation. The schedule is written on the quote; rain and hard cold pause it, because the sealant needs a dry surface.
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
Capping with new windows
When the windows are being replaced, the brickmould is reused or replaced and capped in the same visit. One order, and the coil color is picked against the new frames.
Capping windows that stay
Windows with years left get their wood trim repaired and capped as they are. A fit for buildings where the glass and sash are fine but the paint is not.
Brick walk-ups
Where wood brickmould meets masonry, the cap is bent to the brick line and the joint at the masonry is sealed. We do not nail through the brick face.
Phased by elevation
Street side first, the courtyard next season. The coil color and profile are written on the quote so the later phase matches.
Apartment Window Exterior Capping — Aluminum Wrap, Whole Building: questions, answered
How is aluminum window capping priced on an apartment building?
Per opening, with every window listed on the quote by elevation, floor and unit. What moves the number is how much of the trim is capped, how much soft wood has to be replaced first, and how the upper floors are reached. A building-wide job costs less per opening than a few windows, because the brake is set up once.
Can you cap windows on a three-story apartment building?
Yes, low-rise buildings are the work we do: walk-ups, garden-style and two- to four-story buildings. Upper-floor access is listed as its own line on the quote. We do not take high-rise work that needs swing stages or cranes.
Does aluminum capping hide rot under the trim?
It can, if the installer wraps whatever is there. We probe every brickmould leg and sill before bending any coil, replace the soft wood, and photograph what we found. Rot repair is priced per opening on the quote, so the board sees where the money goes.
Do we need a permit to cap the windows on our building?
It depends on the city and on what else is in the job. Capping alone often needs no permit, but window replacement in a building of five or more units usually does, under the commercial building code. Before we bid, we check the city's contractor licensing and permit rules for that building, and JMB pulls the permit when one is required.
Can the capping color match our windows?
Prefinished trim coil comes in a range of standard colors, and we pick the closest one to the window frames or the existing trim. One color is used on the whole building so later phases match. If you want a color the coil line does not offer, we tell you before the order.
Do residents need to be home while the windows are capped?
No. Capping is outside work, so we do not need into the units. Residents keep windows closed near the crew and clear any balcony or patio items next to the windows we are working on. Expect noise from the brake and the nail gun during work hours.
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.
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Read morePage reviewed October 9, 2026 · JMB Builders LLC, MN license BC809005 · All apartment buildings pages
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