Double hung
Horizontal roller
Casement
Bay & bow
Sliding glass doors
Entry doors
Impact garage doors
PGT
CGIFree in-home measure and quote - PGT, CGI and CWS impact lines compared on your actual openings, style by style
Get your free estimateFast, Reliable Door Installation Across Monrovia
Door installation in Monrovia typically runs $900 – $4,800 depending on whether we’re setting a pre-hung replacement unit or rebuilding a rotted opening in an older home. Most Monrovia jobs take one to two days, though Craftsman restoration work with custom trim can stretch longer. We schedule crews from the Los Angeles office specifically for Monrovia neighborhoods, and we answer the phone at (626) 628-2308 around the clock when a door won’t latch or a frame has shifted. The team at Door Installation knows what’s behind the walls of Monrovia homes built before 1960, and that’s what separates a clean install from a costly one.

Why Lightwell Windows Pasadena Is Monrovia’s Preferred Door Installation Company
Keith Yamada has built the Lightwell Windows Pasadena operation around a simple rule: write the price down before the first tool comes off the truck, and honor it. Monrovia homeowners call us because the houses here are different from what crews see in newer LA subdivisions. Pre-war bungalows on streets like Hillcrest and Canyon have original framing you can’t assume is sound. Mid-century ranches north of Foothill Boulevard have sliding door openings that were undersized from the day they were framed. Our crews probe jamb cores, check for old termite galleries, and verify header sizing before quoting a replacement, because that’s what a Monrovia door actually requires.
Every technician who walks up your front walk is background-checked and uniformed, and they follow the C.A.R.E. values on every job in Monrovia: Clean up like it’s our own home, Ask before moving or touching anything, Respect your family’s time and quiet hours, and Explain the price before the work. Shoe covers go on at the door. Drop cloths protect the floors between the entrance and the work area. A photo of the clean-up is taken before the crew leaves. Those aren’t extras; they’re the standing rule.
And if something isn’t right after the install, the 365-Day Done Right Promise means we make it right. No countdown, no debate. We’re part of the Cedarwell network and have operated to the Cedarwell Care Promise since 2010. Every job gets a written price before any work starts, every time.
Styles & brands we work with









Sliding Glass Door Replacement in Monrovia
Sliding glass door replacement in Monrovia often means removing a single-pane aluminum slider from a mid-century ranch and setting a modern, thermally broken unit into an opening that was never properly sized in the first place. Homes north of Foothill Boulevard, in the foothill slopes above Lemon and Myrtle, run hot in summer and collect fine dust when the Santa Anas blow. A new slider with proper weatherstripping and low-E glass changes how the whole back of the house feels. Most Monrovia slider replacements run $2,400 – $4,800, depending on width and how much framing correction the opening needs.
Reframing Undersized Openings
Original ranch-era slider headers were often a single 4x beam spanning six to eight feet. Under Monrovia’s summer heat load, that header can deflect enough to crack glass and open a gap at the top corner. Before we set a new slider, we check the load path and add a properly engineered header where the old one falls short. The permit gets updated, the math gets done, and the new door closes flat against its seal.
Dust And Heat Sealing
Foothill breezes push grit into door tracks. We set new sliders with sealed rollers and interlocking weatherstripping that closes the gap the old aluminum frames always had. For homes above the 210, this means less dust on the tile and a cooler hallway by late afternoon.
Storm Door Installation in Monrovia
Storm door installation in Monrovia adds a ventilated outer layer to an entry that faces sun, wind, and the occasional sideways rain that rolls up from the Duarte gap. It’s also the practical way to preserve an original Craftsman front door without replacing it. The storm door takes the weather while the old door stays intact behind it. Most Monrovia storm doors run $700 – $1,600 installed, including hardware and full weatherstripping. If the existing jamb is rotted or the threshold has sunk, that work gets priced separately and in writing before we start.
Protecting Original Entry Doors
Monrovia’s Craftsman bungalows along streets like Oakglade and Ivy have front doors that are a century old, with character you can’t buy new. A well-fitted storm door shields that wood from UV and wind-driven rain, extending its life without altering what makes the house look like Monrovia.

Cross-Breeze Ventilation
Storm doors with retractable screens let foothill air move through the front of the house on evenings when the temperature finally drops. Families with kids and pets use that cross-flow instead of running the AC. Our installers set the closer to a soft, quiet swing so it won’t slam on small fingers.
Trusted Brands We Service in Monrovia
We carry Therma-Tru entry doors, CGI and CWS storm-rated units, and ES Windows sliders, so the recommendation fits the home rather than our preferred vendor. For Monrovia’s older openings, Therma-Tru’s rot-resistant frame material has become our default when a jamb needs to be rebuilt. For canyon-facing properties or homes that catch the full afternoon sun, a CWS or CGI door with a low-E glazing package makes a measurable difference in how the entry hall feels by dinner time. Because we’re a local Cedarwell operation, parts and hardware for these brands are stocked for quick turnaround across Monrovia, so a broken roller or a warped threshold doesn’t mean waiting weeks for a ship.
See the difference
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AfterCommon Door Installation Problems We See in Monrovia Homes
- Balloon-framed openings with nothing between floor joists. Pre-1940 Monrovia houses often lack blocking above the door header. A new exterior door hung without adding that blocking will sag and bind within one wet season. We add the framing and note it in the permit drawings.
- Wind-driven dust and old termite galleries weakening jamb cores. Santa Ana winds pack fine grit into every gap, and original wood jambs often hide termite channels from decades past. Techs who don’t probe jamb cores end up cutting an oversize hinge mortise and misaligning the strike plate. We probe before we quote.
- Undersized slider headers on mid-century ranches. Original six- and eight-foot slider openings frequently have one undersized beam overhead. Under summer heat, the header deflects, glass cracks, and the door leaks air. We run the load calculations and upgrade the header when the permit demands it.
- Crumbled masonry behind door frames on older foothill homes. Homes built into the Monrovia foothills sometimes have field stone or unreinforced masonry walls at the entry. The frame looks fine from the outside, but the hinge side has nothing solid to hold fasteners. We shore the opening and add seismic anchorage before setting the new unit.
Pricing for Door Installation in Monrovia, CA
A standard entry door replacement in Monrovia runs $900 – $2,200 for a pre-hung fiberglass or steel unit. A sliding glass door replacement runs $2,400 – $4,800. Storm doors come in between $700 and $1,600. French or double-door installations sit between $1,800 and $3,600. What moves a quote is what’s behind the old door: rotted sub-sills, undersized headers, missing shear panels, or wire runs notched through the jamb studs. On a Foothill Boulevard Craftsman, a rotted back-door opening required a rebuilt jamb, new pressure-treated king studs, and a second shear panel, with the $1,800 allowance for the rotted sub-sill written into the change order before any work started. That’s how every Lightwell job runs. We give you a written price before we touch the opening, and if the wall reveals something the quote didn’t include, we write the allowance, explain it, and get your approval before the work proceeds. Call (626) 628-2308 for a free estimate.
We Also Serve Cities Near Monrovia
Lightwell Windows Pasadena serves Monrovia and the surrounding foothill communities. Our crews regularly work in Arcadia, Duarte, Temple City, and El Monte. If your home sits just over a city line but shares the same pre-war framing or mid-century ranch stock, we’ll bring the same Monrovia playbook to the door. Same written pricing, same C.A.R.E. standards, same 365-Day Done Right Promise.
Serving Monrovia, CA - Our Local Coverage Area
We’re based in the Monrovia area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Door Installation in Monrovia
Opened walls on pre-1960 Monrovia homes frequently reveal outdated wiring stapled through jamb studs, missing header blocking, failed waterproofing at the threshold, or termite-damaged king studs. Any of those triggers a permit update because the inspector will require the framing to meet current code before we close the wall. We handle this by putting realistic allowances in the original quote and pricing any surprise in writing before we touch it.
You can keep it. We weatherize original Craftsman lights by re-bedding the glass, adding bronze or brass weatherstripping that matches the existing hardware finish, and sealing the frame without changing the door’s profile. On Foothill Boulevard homes where the light is part of the historic character, we’ll recommend a storm door to take the weather while the original stays intact. Call (626) 628-2308 to have us look at yours.
We open the wall, measure the actual deflection, run the load calculation for the span, and replace the undersized header with a properly engineered beam. That typically adds $900 – $1,800 to a slider job depending on the span and whether we need temporary shoring. The permit gets updated before the new door goes in, so the final inspection passes on the first visit. Get an exact quote with a free estimate at (626) 628-2308.
A door permit itself doesn’t usually drag in the windows, but if we widen or structurally alter the opening, the building department may require the adjacent glazing to meet current solar heat gain limits. That’s rare on simple replacements, but it does happen on wide slider retrofits. We’ll flag that possibility during the estimate so the quote is honest from day one. Call (626) 628-2308 for a written estimate that covers the real scope.
Rotted sub-sills and termite-damaged jamb studs are the two most common surprises in Monrovia homes built before 1960. Rebuilding a jamb and sub-sill typically adds $800 – $1,800 to the door installation depending on how many studs are damaged and whether new shear panels are required. We write the allowance into the original quote and get your signature on a change order before we do anything, so the number you approve is the number you pay. For a free estimate, call (626) 628-2308.
Written by Keith Yamada, Owner at Lightwell Windows Pasadena, serving Monrovia door installation needs with written pricing and the 365-Day Done Right Promise.
Six Reasons Homeowners Choose Lightwell Windows Pasadena
Laminated glass and reinforced frames hold up to wind-driven rain, hail and flying debris, so your openings stay sealed when the weather turns.
Low-E insulated impact glass from our manufacturer lines commonly cuts monthly cooling bills 20-30%.
Laminated impact glass shuts out up to 40% of outside noise - traffic, neighbors, weather.
Monitoring services run $30-90 a month. Laminated impact glass resists forced entry around the clock, with no subscription.
Tighter seals and insulated glass even out hot and cold rooms and stop the drafts at the frame.
A full impact package upgrades curb appeal, buyer confidence and appraised value in one project.