Impact Windows or Impact Doors: What Should You Replace First?

The short answer: if you are protecting the house against storm damage, start with the largest and most exposed openings — usually sliding glass doors and entry doors. If you are trying to reduce your insurance premium, understand first that partial protection often earns no opening protection credit at all, because the rating is set by the weakest opening in the house.

The rule that changes everything

Florida's wind mitigation credit for opening protection is not averaged. It is set by the least protected glazed opening.

Replace nineteen windows and leave one original sliding glass door, and for opening protection purposes the house is rated by that door. This catches a lot of people out, and it is worth knowing before you plan a phased project rather than after.

There is more detail in Wind Mitigation Inspection: What the Inspector Actually Checks.

So the honest framing is this. A phased project is completely reasonable for spreading cost and for reducing physical risk. It is usually not a way to get a partial insurance credit. If the premium reduction is your main goal, budget for doing every glazed opening, even if it takes longer to get there.

If your goal is storm protection: start with the big openings

Not all openings carry the same risk. Two things drive it: size and exposure.

Large openings carry more total wind load and present a bigger target for debris. A twelve-foot sliding glass door facing a back yard is a far larger exposure than a small bathroom window, and it is usually the single most vulnerable element on a South Florida house.

Exposure matters too. Openings facing open water, open fields, or a long unobstructed fetch see higher loads than openings sheltered by neighbouring structures. Corners and gable ends see higher local pressures than the middle of a wall.

A reasonable order for most homes:

1. Sliding glass doors and large patio doors. Biggest span, biggest load, most common failure point. Patio doors and multi-panel sliders belong here.

2. Entry doors with glass. An entry door with decorative glass, or with sidelights and a transom, is a glazed opening. Losing the front door during a storm is both a structural and a security problem. French doors fall in this group too.

3. Large fixed and picture windows. Picture windows and bay windows on exposed elevations.

4. Operable windows on exposed elevations. Single hung, double hung, casement and slider units, prioritised by which way they face.

5. Small and sheltered openings. Bathroom and utility windows on protected elevations.

Do not forget the garage. A garage door is the largest single opening on most houses, and an unrated one can fail early and pressurise the whole structure.

Doing windows and doors together is usually cheaper

When the work is planned as one project rather than two, several costs stop being duplicated. One permit rather than two. One measurement visit. One mobilisation of the crew. One final inspection. And one consistent product specification, so the finishes match across the house.

Splitting a project across two seasons often costs more in total than doing it once, even before accounting for the delayed insurance benefit.

When phasing genuinely makes sense

There are good reasons to phase:

The budget genuinely does not stretch, and you want the highest-risk openings covered now rather than nothing covered for another year. A specific opening is already failing — a rotted frame or a door that no longer seals. An HOA or architectural committee has approved part of the work and is still reviewing the rest. Or you are staging around a larger renovation.

In all of those cases, phase by risk, and go in knowing the insurance credit will come when the last opening is done.

What we would ask at your house

When we measure, the questions that actually decide sequencing are: which elevations face the most open exposure, which openings are largest, what is the design pressure at your specific address, is there an opening that is already failing, and what is the goal — risk reduction, insurance, comfort, or resale.

The answer is different for a barrier-island home in Fort Lauderdale than for an inland home in West Palm Beach, and different again for a commercial property.

Get it sequenced properly

We measure every opening, give you a fixed written price per opening, and will tell you honestly which ones matter most if you are not doing everything at once. No pressure to buy the whole house on day one.

Book a free in-home measurement or call (561) 464-6272.

FL License #CGC1530499 • In-house W-2 crews • Fixed-price written quotes • Permits pulled directly with your local building department.