Porch/Patio Enclosure Cost Calculator

Estimate the cost to enclose a porch or patio as a screened room, 3-season room, or fully insulated 4-season room.

Results

Visualization

How It Works

Enclosing a porch or patio ranges from an affordable screened-in porch to a full 4-season sunroom. Costs vary dramatically based on the level of enclosure, with screened porches at $30-$50/sqft and 4-season rooms at $150-$250/sqft including HVAC.

The Formula

Total = Framing/Walls + Roof + Foundation (if needed) + Electrical + HVAC (4-season) + Permits

Variables

  • Framing/Walls — Screened $30/sqft, 3-season $70/sqft, 4-season $150/sqft
  • Roof — Flat/shed $18/sqft, gable $28/sqft, cathedral $42/sqft
  • Foundation — $22/sqft if new slab needed, $0 if using existing
  • HVAC — $25/sqft for 4-season rooms with heating and cooling

Worked Example

For a 200 sq ft 3-season room on an existing slab with a shed roof: Framing $14,000 + Roof $3,600 + Electrical $2,400 + Permits $800. Total = $20,800 ($104/sqft).

Practical Tips

  • A screened porch is the most budget-friendly option and keeps insects out effectively
  • 3-season rooms use single-pane windows and work from spring through fall
  • 4-season rooms require insulated walls, dual-pane windows, and dedicated HVAC
  • Using an existing concrete slab saves $4,000-$10,000 in foundation costs
  • Check if the enclosure will change your property tax assessment before building

Frequently Asked Questions

What is the difference between 3-season and 4-season?

A 3-season room has single-pane windows and no HVAC, usable in warm months. A 4-season room is fully insulated with heating/cooling for year-round use.

Do I need a permit for a porch enclosure?

Yes, virtually all porch enclosures require a building permit since they change the structure. 4-season rooms also need electrical and HVAC permits.

Does a sunroom add home value?

A 4-season sunroom typically recoups 50-65% of cost at resale. Screened porches recoup 70-85% because of their lower cost relative to perceived value.

Can I enclose my existing deck?

Yes, but deck framing may need reinforcement to support walls and a roof. A structural assessment is required before proceeding.

How long does a porch enclosure take?

Screened porches take 1-2 weeks, 3-season rooms 2-4 weeks, and 4-season rooms 4-8 weeks to complete.

Last updated: March 20, 2026 · Reviewed by the RemodCalcs Editorial Team