Front porch cost

Building a front porch costs $60 to $200 a square foot, typically around $110. A modest 6 by 20 foot porch is therefore $7,200 to $24,000. Adding a roof is roughly half of that cost, and it is what separates a stoop from a porch.

The foundation and the roof are the money. The decking and the railing are what people choose and they barely move the total.

What it costs

Footings decide the budget

A porch must be supported below the frost line, which is 12 inches in Georgia and 48 inches or more in Minnesota. That single number changes the cost of every footing on the job, and it is why the same porch is meaningfully cheaper in the south.

The other structural question is whether the porch is attached to the house or freestanding. Attached means a ledger board bolted through the rim joist with proper flashing, and that flashing is the most common source of rot on porches and decks. Freestanding costs a little more in posts and avoids the detail entirely.

Ask which the contractor is proposing and, if attached, how the ledger is flashed.

The roof is the reason to do it

An unroofed porch is a deck at the front of the house. It gets used in good weather.

A roofed porch is usable in rain, protects the front door and its finish, shades the front rooms in summer, and is what makes a house read as having a porch at all. It costs roughly $50 to $80 a square foot more.

Getting the roof right:

• Tie into the existing roof properly, with step flashing woven into the shingles, not a bead of sealant along the wall
• Match the pitch and the overhang to the house, or it looks bolted on
• Get the header height right so it does not cut across a window from inside
• Vent it, or a warm roof over an open porch becomes a condensation problem

What it does for the house

Front porches return around 60 to 80% at resale in most surveys, and the number understates it because the effect is on how quickly a house sells and on the first photograph in the listing.

The stronger case is use. A covered front porch is the cheapest usable square footage you can add to a house, at $110 a foot against $200 to $500 for conditioned space.

Where it does not work: on a house with no architectural place for one, on a busy road, or where a porch would darken the front rooms significantly. That last one is real and worth thinking about before committing, because a deep porch on a north elevation takes light out of the living room.

Frequently asked questions

Do I need a permit?

Almost always for anything structural, roofed or attached to the house. A ground-level stoop under a certain size is sometimes exempt. The inspection at footing stage is worth having regardless.

How long does it take?

Three to six weeks for a roofed porch, one to three for an open one. Footings need inspecting before they are poured and concrete needs curing, and both add waiting days rather than working ones.

Wood or composite decking?

On a covered porch, either works and wood looks more appropriate on a traditional house. On an exposed porch, composite avoids the annual refinishing. Tongue and groove porch flooring, the traditional option, must be under a roof.

Can a porch be added to any house?

Structurally usually, architecturally not always. A porch that does not match the proportion and roof line of the house reads as an addition. This is one of the few projects where an architect's afternoon is worth the fee.

Screened or open?

Screening a porch costs $10 to $25 a square foot and roughly doubles the months it is used in mosquito country. It also makes it read as a room rather than a front porch, which changes the front of the house. Many people screen a back porch and leave the front one open.