Replacing a patio door sounds straightforward until you start weighing how you actually live with it. In Redmond, Washington, where months of drizzle give way to bright, lake-reflecting summers, a patio door does more than close a wall opening. It shapes how you move between deck and kitchen, how daylight reaches the back of the house, and how your heating bill behaves when the east wind kicks up off the plateau. The two dominant choices, sliding and French, both work beautifully when matched to the right home and lifestyle. They also fail quietly when chosen for the wrong reasons.
I have installed and serviced hundreds of patio doors across neighborhoods from Education Hill to Overlake. If you’re staring at a soggy threshold or a fogged glass panel, here’s the decision-making approach I use with clients, tuned to Redmond’s climate, building norms, and the way families here actually use their spaces.
What sliding and French patio doors do well, and where they don’t
A sliding door excels in compact areas and along view corridors. Because the panel glides on a track rather than swinging, you lose zero floor space to the door arc. In kitchens where an island sits close to the opening, that matters. Sliders frame wider uninterrupted glass, which means longer sightlines across a backyard lined with Douglas firs or a small play lawn. Modern units usually have a fixed panel plus one active panel, though two-panel, three-panel, and four-panel configurations can open up huge spans. In Redmond tract homes from the 1990s and 2000s, a standard 6-foot by 6-foot-8 slider is the default footprint. Upgrading within this size avoids structural work and keeps costs predictable.
French patio doors bring symmetry and a sense of architecture. You feel it when both panels swing open and the room breathes, a true indoor-outdoor threshold. That wide clear opening is friendlier for moving furniture, wheeling in a grill, or keeping a party flowing on summer evenings. Well-made French doors seal tightly with multi-point hardware and can match the look of traditional trim if you have divided-light windows, a craftsman porch, or a more formal dining room that opens to a patio. The tradeoff is space for swing clearance and a different relationship to weather, since an outswing or inswing choice affects performance in Redmond’s wind and rain.
Neither style is inherently better. The right door solves the space, improves light, manages water, and fits the house’s architecture without calling attention to itself.
Climate is not an afterthought around Lake Sammamish
Puget Sound weather trains you to respect water and air movement. In Redmond, rainfall totals hover around 35 to 40 inches per year, but the more relevant facts are long wet periods, morning dew, and frequent freeze-thaw cycles from late fall through early spring. Add wind-driven rain from the south and southeast and you have a recipe for rot at thresholds and flanking studs if a door is poorly flashed or the wrong swing is chosen.
Sliding doors, especially older aluminum units, were notorious for collecting water in their tracks. Modern sliders use weep systems, sill dams, and thermally broken frames that move water out while resisting condensation. The details matter. I look for a deep sill with multiple weep paths and removable track covers so you can vacuum out pine needles that otherwise clog drainage. If your slider faces the prevailing wind, invest in a unit with a performance rating designed for higher water infiltration resistance. That spec tells you more than a glossy brochure.
French doors come in inswing and outswing. In our climate, outswing is generally the safer pick for water management because wind pressure pushes the door tighter against its compression seals. Inswing doors can invite water intrusion at the sill if the exterior landing is not protected, correctly sloped, and well flashed. If you must use an inswing, I insist on a sloped pan, an adjustable inswing threshold, and head protection from a small roof or deep eave. If your patio is fully covered, the inswing vs. outswing calculus changes, but the basic rule holds: let the weather push the door shut, not pry it open.
Space planning drives the first decision
Before you compare glass packages or finishes, step back and look at how furniture and people move around the opening. If you regularly tuck a breakfast table or a sectional right up to the door, a sliding panel keeps that footprint intact. If your patio landing is narrow, an outswing French door may smack a railing or create a pinch point. On the other hand, if your dining chairs or a bar cart live inside the room where the door is, an inswing will fight the furniture.
Clear opening width matters for function. A standard two-panel slider with one active panel gives you about half the rough opening as pass-through space. In a 6-foot frame that means roughly 34 to 36 inches clear. Two active French panels in a same-size frame give you the full width minus jambs and astragals, often 58 to 60 inches clear. If you host large gatherings, move coolers, or have mobility needs that benefit from more room, that French configuration feels generous. For sliders, you can mimic that experience by moving to a three-panel unit with the center panel active or a four-panel with two center panels that meet and open wide, but that usually means reframing.
Energy performance, glass, and the way they relate to comfort
Energy-efficient windows and doors are not marketing fluff in Redmond where winter nights dip into the 30s and heat is on for months. Whether you choose sliding patio doors or French, you can spec low-e coatings, argon-filled insulated glass, and warm-edge spacers that collectively drop U-factors into the 0.27 to 0.30 range for many units. The Northwest Energy Efficiency Alliance and local code updates continue to push manufacturers to deliver better thermal numbers.
Two realities from the field: frame material choices and air leakage define comfort beyond what a U-factor chart suggests. Vinyl frames with multi-chamber profiles perform very well thermally and are common with vinyl windows Redmond WA homeowners choose for replacement windows Redmond WA projects. Wood-clad frames look refined and insulate well but demand maintenance. Fiberglass offers stability in temperature swings. Aluminum, except thermally broken commercial-grade profiles, tends to feel cold to the touch and can sweat in humid mornings.
Sliders can have slightly higher air infiltration values than well-tuned French doors because the interlock where the panels meet is a moving interface. High-quality sliders use interlocking stiles and tight brush seals combined with compression seals at the jamb. French doors depend on compression seals around the full perimeter and multi-point locks that cinch the panel into place. When installed correctly, both styles can meet tight air leakage specifications. Poor installation overwhelms any factory advantage.
If you are replacing windows Redmond WA homes often pair with door upgrades, keep your glass strategy consistent. For example, if you have south or west exposure, a slightly lower solar heat gain coefficient helps control afternoon heat. North-facing doors can accept higher SHGC to harvest daylight without glare. Picture windows Redmond WA homeowners install near patios often share the same glass package to avoid color differences when light hits the coatings.
Security, pets, and kids
Homeowners worry about sliders being easy to lift or French doors being easy to pry. Both concerns are dated when you buy modern hardware and install it correctly. The anti-lift blocks on sliders prevent panels from being raised out of the track. Multi-point locks on both styles engage at several points up the stile. Tempered glass is required and resists impacts far better than annealed glass.
Practical life details often decide the winner. A slider with a pet panel insert is common, though I prefer integrated dog doors in a French panel when security and thermal performance matter. French doors with both panels active can also make moving a kayak or large planters far easier. For households with toddlers, consider handles and latch hardware that are child-resistant but not adult-frustrating. If you are already planning door replacement Redmond WA projects that include entry doors Redmond WA upgrades, you can align handle finishes and keying systems so you are not juggling different keys.
Cost ranges and where money matters
Prices vary widely depending on size, frame material, glass package, and brand. For a standard two-panel 6-foot unit, a quality vinyl sliding door often lands in a cost-effective range compared to a wood-clad French door of the same size. Add sidelites, custom stains, or divided lites and the French door tab grows. Fiberglass French doors often split the difference.
What you should not skimp on: the sill system, hardware, and professional installation. A budget door with an excellent sill and careful flashing will outperform a premium door installed carelessly. If you are undertaking window replacement Redmond WA residents often combine with door installation Redmond WA in the same project, bundling reduces mobilization costs and keeps finish details consistent across the elevation.
Installation quality in a wet climate
Window installation Redmond WA contractors perform daily follows a rhythm dictated by moisture management. A patio door opening is essentially a hole in a wall at ground level where splashback, snow melt, and leaf litter move. I advocate for a rigid or flexible sill pan that is sloped, pre-formed, and integrated into the weather-resistive barrier. The pan must kick water to the exterior, not trap it under the door. Side jamb flashing should lap over the pan, and head flashing must shingle correctly with the WRB. On older homes with ship-lap or T1-11 siding, pay attention to how the head flashing tucks behind or integrates with trim so wind-driven rain Redmond Windows & Doors does not find a path around the door.
Adjusting the frame square, level, and plumb is half the battle. The other half is setting reveals and lock engagement to draw seals tight without over-compressing them. A well-installed slider glides with one finger. A well-installed French door closes with a single smooth movement and feels cushioned at the end. If you struggle to latch it on day one, it will only worsen as seasonal humidity swells wood or as the home settles.
If you are also adding casement windows Redmond WA homes often use along kitchens, or double-hung windows Redmond WA homeowners prefer for bedrooms, keep the same crew and flashing details across openings. Consistency prevents odd leaks that appear where two different methods meet.
Style and curb appeal
Architecture should guide the choice rather than fight it. Many Redmond homes built over the past three decades lean contemporary - clean rooflines, larger glass areas, simple trim packages. Sliding doors fit that language with thin profiles and bigger panes. If your house leans northwest Craftsman with tapered columns and divided lights, a French door with true or simulated divided lites ties the patio opening to the rest of the fenestration. Bay windows Redmond WA houses use to anchor dining nooks often pair well with French doors nearby, while bow windows Redmond WA homes occasionally feature along living rooms look better next to sliders that keep glass uninterrupted.
Color matters. Vinyl windows Redmond WA owners choos