7250 SW 39th Terrace, Miami, FL 33155
Licensed & Insured · South Florida
HVHZ Structural Opening Modifications

Open the wall. Keep the structure strong.

Enlarge a window, convert a window into a door, or redesign an opening with the engineering, permits and structural reinforcement South Florida homes require.

Opening modifications are not simple window swaps.

Separate opening-modification permit when the opening size changes.
Florida-licensed engineering for load-bearing walls, headers and wind loads.
Rebar, concrete, inspections, impact product installation and finish work coordinated by one team.
HVHZ Built for South Florida
2 Permit Tracks
PE Engineer Required
CGC Licensed Structural Scope
Opening Options

Three ways to transform the way your home feels.

Whether the goal is more light, better indoor-outdoor flow or a cleaner architectural layout, each modification has a different structural path.

Window to Door

Convert an existing window into a floor-level access point for impact sliding doors, French doors, pivot doors or multi-panel systems.

Cut opening to size Install new columns/tie downs Steel/footer upgrades if needed

Door to Window

Reduce a door opening into a properly reinforced window opening when a room layout, furniture plan or new interior use needs a cleaner wall.

Introduce stem wall New sill with rebar Interior/exterior patches

Window to Larger Window

Enlarge a window horizontally or vertically for a picture window, wider impact unit, panoramic opening or custom architectural glass.

Cut new opening to size New tie downs/grout-filled cells New sill with rebar Interior/exterior patches
Why This Matters

Changing the opening changes the structure.

In South Florida, the wall around a window or door is part of the home’s structural envelope. When you cut into concrete block, widen an opening, lower a sill, or convert a window into a door, the load path changes.

That means the job needs more than a new impact product. It needs proper layout, engineering, reinforcement, permits, inspections, waterproofing and finish work.

A larger opening is only safe when the new columns, sill and potential reinforced tie beam are rebuilt to carry HVHZ wind loads and support the product anchoring required by the NOA.
Cost Transparency

What does an opening modification cost?

$5k–$35k

Typical structural add-on range per opening for enlargement work in South Florida. This is separate from the impact window or door product and its installation.

1

Engineering + sealed drawings

The engineer determines load path, reinforcement, header requirements and wind-load compliance.

2

Separate permit + review

When the opening changes, the structural modification is reviewed separately from the window or door product permit.

3

Cutting, rebar + concrete

The cost includes saw-cutting, reinforced jambs, sill work and header/tie-beam work where required.

4

Inspections + finish work

Structural inspections, anchoring inspections, exterior stucco repair, interior drywall and close-out are part of the real scope.

!

Not included in that range

The impact window or door itself and its installation are separate line items. The structural add-on keeps the budget honest.

Our Process

Engineered before anyone starts cutting.

Opening modifications need the right sequence: review, engineering, permits, reinforcement, inspections and finish work — all coordinated before the new impact product goes in.

Watch the breakdown See why opening work is structural. Watch on YouTube →

Site review

We review the opening, wall type, project goal and potential load-bearing conditions.

Engineering

A Florida-licensed engineer prepares the details for jambs, sill, header and reinforcement.

Permits

The opening-modification scope follows its own permit path when the opening size changes.

Structural work

The block is opened carefully, then reinforced with rebar, concrete and header work when required.

Inspections

Reinforcement and product anchoring are inspected before the work is closed up.

Finish + close-out

We complete the impact installation, stucco, drywall, trim and permit close-out.

Why Bigfoot

One accountable team for the structure and the finish.

A simple window installer is not the right fit for a wall modification. Opening modifications can involve cutting concrete block, rebuilding structural jambs, coordinating engineering, waterproofing the opening and closing permits.

Bigfoot Windows & Roofing is built for projects where the details matter: structure, envelope, water management and final appearance.

Start My Opening Review →
Licensed Scope
CGC1531370 Certified General Contractor
CCC1333168 Certified Roofing Contractor
CRC1331693 Certified Residential Contractor
SCC131153098 Certified Specialty Contractor
Free Consultation

Tell us what opening you want to change.

Share the address, project type and contact details. Our team will review what kind of structural scope, permit path and product options may apply.

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FAQ

Opening modification questions homeowners ask first.

The biggest mistake is treating this like a normal window replacement. It is not. The structure, permit path and inspection sequence are different.

Why do I need a separate opening-modification permit?

Because changing the size of the opening changes the structure. The impact window or door permit covers the product and anchoring. The opening-modification permit covers cutting the wall, reinforcing the opening, and proving that the new opening is structurally compliant.

Why is a structural engineer required?

A Florida-licensed structural engineer determines whether the wall is load-bearing, sizes the reinforcement, confirms header requirements and prepares signed/sealed drawings for the building department.

Can you just cut the concrete block and install the window?

No. In HVHZ areas, the opening must be rebuilt so the impact product has a proper reinforced substrate to anchor into. Cutting without reinforcement can void the product assumptions and fail inspection.

Does the $4,000–$8,000 range include the impact window or door?

No. That range is the structural add-on for engineering, permit, cutting, rebar, concrete, inspections and patch-back. The impact product and its installation are separate.

Will this delay my project?

Yes, that specific opening usually takes longer because engineering, permit review, concrete curing and inspections add time. Other standard replacements can often move on a separate schedule.

Ready to change the opening without risking the structure?

Tell us what you want to modify. We will help you understand the structural scope, permit path and next steps before anyone starts cutting.

Updated July 2026