Low Threshold Patio Door Replacement — Choosing a Low-Sill Unit
Someone in the house catches a toe on the patio door sill, or a walker or wheelchair has to bump over it.
Reply within one business day. Or call / text 763-204-2099.
A low threshold patio door is a new slider or hinged unit ordered with a low-profile sill, so the step from the floor to the deck is a short lip instead of a tall hump. JMB Builders orders low-sill patio doors across the Twin Cities metro and installs them with a sill pan and drainage that suit Minnesota snow and splash, so the lower step does not put water on the floor. Priced per door, reply within one business day.
- Priced per door, low-sill unit included
- Slider or hinged, low-profile sill from the factory
- Set in a sill pan with the deck drainage checked
A standard sliding door sill stands up a couple of inches off the floor and the track sits on top of that. It is a trip point for anyone with a bad hip and a wall for a wheelchair. Several manufacturers now offer a low-profile sill as an order option: a shallower track with a smaller lip, sometimes with a ramped interior edge. The step is still there, but it is a lip you can roll over or shuffle across instead of a hurdle.
The catch is water. A tall sill is tall because it keeps rain, snowmelt and the splash off the deck out of the house. A low sill has less height to work with, so the install has to make up the difference: a sill pan under the door, flashing up the jambs, a deck surface that sits below the sill and drains away from it, and a cover over the door where that is possible. On a Minnesota walkout where snow drifts against the door, a low sill with no overhang is a wet floor in March.
This page is about choosing and installing a new unit with a low sill. If your existing door's threshold is rotted or worn, that is a repair; see our exterior door threshold replacement page. We order low-sill sliders and hinged doors from options such as Andersen, Pella, Marvin and ProVia and tell you which ones fit your opening and your exposure.
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
- Who the door is for: a walker, a wheelchair, or just an easier step, so we pick the right sill profile
- Slider or hinged, frame material and color
- Photos of the door from inside and outside, with a close-up of the sill and the deck surface right outside it
- Paint color for the new casing if you want it painted — quoted as its own line
What JMB supplies
- Measurement of the opening and the order for a low-sill slider or hinged door with screen
- A frank word on whether your exposure can handle a low sill, and what has to change outside if it can
- Removal and haul-away of the old door, frame and trim
- Sill pan, flashing tape, backer rod, low-expansion foam and exterior sealant
- Subfloor or framing repair at the sill, quoted from the photos
- Interior casing and exterior trim; a tapered interior transition strip where the floor meets the sill
- Painting of the new casing when you want it, quoted as a separate line
- Photos of the finished door in your job folder
How it is priced: per door
Quoted in writing from your photos, with a reply within one business day. What moves the number:
- Slider vs hinged door, and the width of the unit
- Frame material and color; low-sill options are not offered in every line
- Glass package: low-e, argon, tempered or triple pane
- Deck or landing work needed so the surface outside drains away from the lower sill
- Rot at the subfloor or rim joist once the old door is out
- Interior floor transition at the sill, and the flooring type it meets
- Painting the new casing, quoted as a separate line
Send a photo of the sill from inside and one from outside at deck level so we can see how high the deck sits against the door. Tell us if there is a roof or overhang above the door.
How long it takes
One low-sill slider in a sound opening: most of a day on site. Add time when the deck boards or landing need adjusting so water runs away from the new sill.
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
Low-profile sill slider
A two- or three-panel slider ordered with the manufacturer's low sill. The track is shallower and the interior lip is shorter. Best where the door is covered or the deck is a step down and drains away.
Hinged door with low sill
An in-swing or out-swing hinged patio door with a low saddle threshold. An out-swing unit can have a lower interior lip because the door seals against the sill from outside. Needs the swing room on the deck.
Standard sill with a ramped transition
When the exposure is too wet for a low sill, a standard door with a tapered threshold ramp inside and a small ramp outside gets most of the benefit and keeps the water out. We will say so if this is the right answer for your door.
Low Threshold Patio Door Replacement — Choosing a Low-Sill Unit: questions, answered
Can a sliding patio door have a low threshold?
Yes. Several manufacturers offer a low-profile sill as an order option on their sliders. The track is shallower and the lip you step over is shorter than a standard sill. It is still a lip, not a flush floor, because the track has to hold the panel and keep water out. We tell you the exact sill height for each line we quote so you know what you are getting.
Will a low sill patio door leak in Minnesota?
It can if the outside is wrong. A low sill has less height to stop splash and snowmelt, so the deck surface has to sit below it and drain away, and an overhang helps a lot. We set every low-sill door in a sill pan with flashing up the jambs, and we tell you if your exposure needs a ramp or a standard sill instead. A north-facing covered door is a good candidate; a south walkout with drifting snow and no roof is not.
Is a low threshold patio door good for a wheelchair or walker?
It is a real improvement. A standard slider sill is a hump a wheelchair cannot clear alone; a low-profile sill is a short lip that a chair rolls over and a walker clears without lifting. For a fully flush path, an out-swing hinged door with a low saddle and a ramped interior strip gets closest. Pair the door with a lever or D-handle and the whole step gets easier.
Can you lower the threshold on my existing patio door instead of replacing it?
No. The sill height is built into the door frame, so lowering it means a new unit with a low-profile sill. Repairing or swapping a worn threshold on an entry door is a separate job and a different page. If the rest of your slider is in good shape and the sill is just damaged, start there; if the door is old and the step is the problem, a new low-sill unit solves both.
Does a low sill door need a different deck?
Sometimes. The deck boards or landing right outside the door should sit below the sill and slope away from the house. If your deck is level with or above the sill, water and snow will find the lower lip. We check the deck height in your photos and quote the adjustment if it is needed, which is often just lowering a few boards or adding a drainage gap at the house.
Which patio door brands offer a low profile sill?
Options such as Andersen, Pella, Marvin and ProVia offer a low or accessible sill on at least some of their slider and hinged lines, and the exact height varies by line and material. Not every frame color or size comes with it. Tell us who the door is for and which way it faces and we quote the lines that fit, with the sill height for each.
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 10, 2026 · JMB Builders LLC, MN license BC809005 · All doors pages
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