How to Measure for Hurricane Shutters

Why Measurement Accuracy Matters More for Hurricane Shutters

Hurricane shutters aren’t decorative trim — they’re structural protection that has to stay anchored to your home during 100+ mph wind gusts and direct impact from debris. That requires precision that most window treatments don’t.

Get the measurement wrong by a half-inch on a decorative panel and it’s a cosmetic issue. Get it wrong on a hurricane shutter and you’ve got gaps that let wind pressure equalize inside the opening — which is exactly the scenario that causes window failures and interior pressurization during a storm.

AHS measures every opening ourselves, for free, before quoting. You don’t need to measure anything yourself before calling us. But understanding what we measure (and why) helps you prepare for the consultation and make informed decisions about product selection.

This guide walks through the measurement process so you know what to expect — and how to spot corners-cut quotes from competitors who skip the detailed measurement step.

What Measurements We Take for Each Opening

For every window, door, and skylight that will receive a shutter, we record:

1. Opening width and height

Measured at three points each (top, middle, bottom for width; left, middle, right for height). Most openings aren’t perfectly square — especially on older homes that have settled — and we size the shutter to the largest dimension at each axis.

2. Rough opening vs. finished opening

The “rough opening” is the framed hole in the wall; the “finished opening” is the visible trimmed area after the window is installed. Different shutter products mount to different references:

• Rolldown shutters typically mount outside the finished opening, with the housing box spanning above the window trim
• Accordion shutters mount to vertical tracks on either side of the finished opening
• Bahama and Colonial shutters mount above or beside the finished opening with hinges or rails
• Panels typically mount to permanent tracks/anchors that sit just outside the finished opening

We record both dimensions so we can select the optimal mounting method for each opening.

3. Projection clearance

How far the shutter will stand out from the wall when deployed — and what’s in the way. We check for:

• Exterior lights, gutters, downspouts
• Shutters from neighboring windows that might interfere
• Plantings, HVAC units, decks, patios
• Roof overhangs and eaves

Projection clearance can rule out certain product types on certain openings. A window directly under a roof eave may not have enough vertical clearance for a rolldown housing box, for example.

4. Wall substrate

What the shutter anchors INTO matters as much as the shutter itself. We document:

• Wood framing (typical on most homes) — standard anchoring
• Concrete or block (common on foundations and some coastal homes) — requires different fasteners
• Brick veneer with wood framing behind — requires anchoring through to the structural frame
• Vinyl siding over wood framing — requires mounting technique that avoids crushing the siding
• Stucco or hardiboard over framing — requires sealing to prevent water intrusion at anchor points

Using the wrong fastener for the substrate is one of the most common causes of shutter failure in actual storms. We match the anchoring system to the wall type on every opening.

5. Special considerations

• Windows in bays or bump-outs may require custom angled mounting
• Arched or round-top windows require custom-shaped shutters or different product selection
• Sliding glass doors often need wider-span accordion or rolldown systems
• French doors may require two separate shutters with a center meeting stile
• Skylights require specialized rolldown or impact-rated covers
• Corner windows may need two shutters that interlock or overlap

The Tools and Techniques We Use

Professional shutter measurement uses more than a tape measure. Our installers carry:

• Laser distance measurers for large openings (sliding doors, garage openings) where tape-measure accuracy degrades over 8+ feet
• Digital levels to confirm openings are actually square (critical for rolldown housing box alignment)
• Plumb lines and string levels for vertical alignment on multi-story installations
• Moisture meters on older homes or homes with visible water staining — we won’t anchor to rotted framing
• Photography documentation — every opening gets photos before, during, and after measurement

Why DIY Measurement Is Risky (Even If You’re Handy)

We sometimes get calls from homeowners who’ve measured their own openings and want to order shutters direct. Two things to know:

1. Manufacturer tolerances matter. Most rated shutter manufacturers require dimensions to 1/8-inch accuracy for custom-fabricated panels. Hitting that consistently across a dozen openings using a standard tape measure is harder than it looks — and manufacturer errors caused by incorrect measurements aren’t typically covered by warranty.

2. Manufacturer installation requirements. Most rated shutter manufacturers require professional installation by authorized dealers to preserve the rating. A shutter installed by a DIYer typically voids the ASTM/TAS rating, which means you can’t document it for insurance wind mitigation credits. The insurance discount alone usually exceeds the cost of professional installation.

3. Substrate surprises. You don’t know what’s behind the siding until you open it up. A contractor who’s anchored thousands of shutters knows what to expect from 1960s block, 1990s wood framing, or modern ICF construction. DIY surprises at the anchor stage are hard to recover from safely.

That said — if you’re absolutely determined to self-measure, the minimum accurate process is:

1. Measure width at top, middle, and bottom — use the SMALLEST measurement
2. Measure height at left, middle, and right — use the SMALLEST measurement
3. Check if the opening is square by measuring both diagonals — if they differ by more than 1/4 inch, the opening is out of square and needs professional assessment
4. Measure from finished wall surface to existing obstructions (lights, gutters) for clearance
5. Photograph each opening with a tape measure in the photo for reference

Even with perfect measurements, you still need a dealer to order the products, and most dealers won’t fabricate without visiting the site.

Your Appointment

What Happens at Your AHS Measurement Appointment

The consultation takes 45 minutes to 2 hours depending on house size:

1. Walkthrough. We walk every elevation of the house with you, note which openings need protection, and discuss your goals (full coverage vs. phased install, aesthetic preferences, budget).
2. Measurement. We measure every opening using the process above.
3. Product discussion. Based on the measurements, clearance, and your aesthetic preferences, we recommend specific product types for each opening. Mixed installations are common — rolldown on oceanfront elevations, accordion on sides, rated Bahama on front facade, for example.
4. HOA review. If you’re in an HOA community, we identify products likely to clear architectural review and discuss documentation.
5. Fixed-price quote. We leave you with a written quote for the specified products and installation. No measurement surprises afterward.
Next Steps

Getting Started

Call (910) 256-1288 or request a free estimate through our cost calculator. We serve coastal NC and SC — New Hanover, Brunswick, Pender, Onslow, Carteret, Craven, and Horry counties.

Common Questions

Frequently Asked Questions

Do I need to measure my windows before calling AHS?+

No. AHS measures every opening at the free in-home consultation. Homeowners don’t need to do any preparation beyond making sure we can access the exterior of each window and door during the appointment.

How accurate do hurricane shutter measurements need to be?+

Most rated shutter manufacturers require dimensions to 1/8-inch accuracy. AHS measures at three points on each axis and uses the governing dimension. Professional measurement tools (laser distance measurers, digital levels) make this accuracy achievable where a standard tape measure alone can’t.

What if my windows are irregular or custom shapes?+

Arched windows, angled bays, and corner windows all require custom measurement approaches. AHS handles irregular shapes routinely — the consultation identifies which product types work on each opening and whether any custom fabrication is required.

Can AHS shutter a sliding glass door that’s wider than standard?+

Yes. Wide sliding glass doors typically receive either a wide-span accordion or a rolldown system. The consultation measurement confirms clearances and selects the appropriate product.

What if my home has different substrates (brick on some walls, siding on others)?+

Each opening is evaluated and anchored appropriately for its substrate. This is normal — most coastal homes have a mix of materials. AHS installers carry fasteners and sealants for every common substrate.

How long between measurement and installation?+

Custom products are typically fabricated in 2-6 weeks depending on product type and quantity. Installation is scheduled once fabrication completes. Standard panel shutters ship faster; custom accordion and rolldown systems take longer. AHS provides a specific timeline in the quote.

Skip the measuring — we handle it

Free on-site measure with every AHS estimate. Trained techs, engineering-grade accuracy, no guesswork.

Get a Free Quote (910) 256-1288