Apartment Window Rot Repair — Rough Openings Found on Tear-Out
You are replacing windows across a building and the old frames on the weather side are soft.
Reply within one business day. Or call / text 763-204-2099.
Apartment window rot repair fixes the soft rough sill, jack studs and sheathing found when old windows come out. On apartment buildings JMB Builders sets a per-opening price for a typical repair on the quote, does it the same day so the unit is closed that night, and stops and calls you with photos before anything bigger. Twin Cities metro to St. Cloud; send photos for a reply within one business day, or book a free in-home estimate.
- Set per-opening price for typical rot
- Stop and call, with photos, above that
- Opening closed the same day
On an older apartment building, the rot is rarely spread evenly. It sits under the windows on the weather side, under units where a tenant ran a humidifier all winter, and below openings where the sill was painted shut years ago. Nobody can count it from the outside, so a bid that ignores it turns into a string of change orders, and a bid that guesses high on every opening overcharges the dry ones.
We price it the way a board or asset manager can approve ahead of time. The quote defines a typical repair: cut out and replace the rough sill, sister the bottom of the jack studs, patch the sheathing under the window. That repair carries a set price per opening. When we find more than that on tear-out, such as a rotted header or soft framing running down into the wall, we stop, photograph it with a tape in the shot, and call you before going further.
Every repaired opening is photographed open and closed and logged by unit, so you know which stacks had trouble. Each opening is still closed the same day it is opened. A rotted header or framing that carries load beyond a window opening is looked at by an engineer when the size calls for it.
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
- Approval of the typical-repair price per opening when you sign
- A contact who can say yes or no by phone during install days
- Access to each unit, with the notice to residents your lease and Minnesota law require
- Any past leak or maintenance records by unit, if you have them
What JMB supplies
- One in-person measure of every opening, with suspect sills probed from inside and out
- A quote with a defined typical rot repair and its per-opening price
- Treated lumber, sheathing patch, sill pan and flashing tape
- Stop-and-call with photos before any repair larger than the typical one
- Photos of each repaired opening, open and closed, logged by unit
- Each opening closed and weather-tight the same day
- 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:
- How many openings need the typical repair, counted on tear-out
- Repairs larger than typical: header, deep framing, rim or sheathing beyond the opening
- Siding or brick around the opening that has to be cut back and patched
- Interior drywall or trim damaged by the same water
- Floor height and access to the exterior of the opening
- Whether the window is going in as full frame, which shows the rot, or as an insert
Send a photo of the worst sills outside and inside, with a screwdriver or tape for scale. The per-opening rot price is written on the quote before you sign.
How long it takes
The typical repair adds a few hours to the opening and is finished the same day. Anything larger waits for your yes, then is scheduled so the unit is still closed that night.
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
Typical repair
Rough sill replaced, jack studs sistered at the bottom, sheathing patched under the window. Set price per opening, done without a call, photographed.
Beyond typical
Header, king studs, framing below the sill or sheathing past the opening. We stop, send photos with scale, price it, and wait for your yes.
Insert windows over soft frames
An insert sits in the old frame, so rot in that frame stays. When we probe a soft frame at the measure, we tell you that opening should go full frame instead.
Rot log by unit
Every repaired opening listed with its unit and photos. Useful for reserve studies, for the next phase, and for finding the leak that caused it.
Apartment Window Rot Repair — Rough Openings Found on Tear-Out: questions, answered
How do you price rot you cannot see until the old windows come out?
The quote defines a typical rot repair and gives it a set price per opening, so you approve it once at signing. We count the openings that need it on tear-out and photograph each one. Anything bigger than the typical repair is a stop, a call and a separate price before we go on.
What happens if you find major rot in an apartment window opening?
We stop, take photos with a tape in the shot, and call your contact with a price and what it involves. The unit is closed up that day either way, with the repair done or the opening sealed temporarily. When the damage reaches framing that carries more than the window, an engineer looks at it when the size calls for it.
Why are only some apartment windows rotted?
Rot follows water: the weather side of the building, units with high indoor humidity, sills that were caulked or painted shut, and openings under a leak higher on the wall. We log the rotted openings by unit and elevation so the pattern shows. If the same stack keeps rotting, the water source above it needs fixing too.
Can insert windows go into rotted frames?
They should not. An insert sits inside the old frame, so soft wood stays in the wall and keeps rotting. When the frame probes soft at the measure, we recommend full frame for that opening and price it that way on the quote.
Do you document window rot for the board or owner?
Yes. Each repaired opening is photographed open and after the repair, labeled by unit and elevation, and saved in your job folder. The invoice lists the repairs per opening against the quoted rate.
Does rot repair make the window replacement take longer?
A typical repair adds a few hours to that opening and is finished the same day. Larger repairs can push that unit's finish by a day, but the opening is closed every night. The schedule for the rest of the building keeps moving.
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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