A barndominium exterior showing a deep wrap-around covered porch with posts and railing along two sides of the building.

Barndominium with Wrap Around Porch in Idaho

A wrap-around porch turns a steel box into a farmhouse. It shades the walls in a hot Treasure Valley or Magic Valley summer, gives the front door a dry landing in winter, and on acreage it is where the evening is spent looking at the fields or the mountains. On a barndominium the porch is usually a lower roof tucked under the eave of a big steel roof, and that is the detail to get right in Idaho: everything that slides off the main roof lands on the porch. The porch also sits in front of bedroom windows and, on wildland edges, it is exactly where embers collect.

What actually changes with this feature

The look is the easy part. These are the decisions that follow from it.

Bedroom windows behind the porch still have to work

An emergency escape opening under a deck or porch must be fully openable and give a path at least 36 inches high to a yard or court. Where a wrap-around porch passes a bedroom, keep the porch floor and roof framing clear of that path, and remember the window's sill must still be no more than 44 inches above the bedroom floor.

Guards where the porch stands high

Wherever the porch floor is more than 30 inches above grade within 36 inches of its edge, it needs a guard at least 36 inches high. On a sloping acreage lot the porch may start at grade on the uphill side and need guards on the downhill side. Plan the rail style for the whole run so the high side does not look like an afterthought.

Close the space under the porch

The Idaho Department of Lands recommends enclosing decks and eaves with 1/8-inch or smaller metal screen, or keeping a clear noncombustible area underneath, and storing firewood at least 30 feet from the house. The dry space under a wrap-around porch, with leaves blown into it, is where an ember lands. Skirt it with metal mesh from the start and keep the firewood stack in the yard, not on the porch.

Depth and orientation

A porch at least 8 feet deep holds chairs and a walkway. On the south and west it shades the walls and windows in summer; on the north it stays icy longer in winter. Many Idaho plans wrap the porch around the south and west, and use a smaller covered entry on the north or east side where the snow lingers.

A barndominium exterior showing a deep wrap-around covered porch with posts and railing along two sides of the building.
Snow from the main roof

A porch under a steel eave carries its own snow and the main roof's

University of Idaho researchers compute a site's ground snow load from its elevation and urge users to verify it with the local authority having jurisdiction; where your city or county runs a building program, its building official sets it for your site. Their 2015 report points designers to the national loads standard for roof slope, unbalanced loads, drifting, roof projections and sliding snow. A porch roof below a slick steel main roof is the textbook case for sliding snow, so size the porch framing for it, or step the porch roof down far enough and keep its eave where a slide will not bury the walkway.

Common ways to build this

Three common ways to lay this out. Yours does not have to match one exactly — this is a starting point for the conversation, not a catalog.

Farmhouse with a two-side wrap

36' x 56' / 2,000 sq ft living / 8' porch on the front and one gable end

The porch runs along the front and turns one corner, with the main door under it and the bedrooms on the far side of the house. The porch roof steps down from the steel eave and is framed for sliding snow.

Full wrap on a single-story ranch

40' x 60' / 2,400 sq ft living / 10' porch on all four sides

A porch all the way around, which puts every bedroom window behind it. Each window keeps a 36-inch-high path to the yard, and the porch skirt is metal mesh against embers.

Wrap-around porch with a screened corner

2,200 sq ft living / 8' porch on three sides / 14' x 16' screened corner

One corner of the porch is screened in for summer evenings. Use metal screen, not vinyl: the Idaho Department of Lands calls for metal on vents and windows, and Idaho Firewise warns that embers can burn through plastic screens.

Barndominium with a Wrap-Around Porch: common questions

6 questions worth settling before this plan is drawn. If yours is not on the list, put it in the survey.

How deep should a barndominium porch be?
Eight feet is a practical minimum for chairs and a walkway; ten or twelve feet makes room for a dining table. Deeper porches shade more wall in summer and keep more snow off the walk in winter, but they also darken the rooms behind them.
Will snow sliding off the steel roof damage the porch?
It can if the porch roof is not sized for it. The ground snow load varies with your site's elevation, and a porch roof below a steel main roof is designed for snow that slides onto it as well as snow that falls on it. Snow guards on the main roof are another option.
Can a bedroom window open onto a covered porch?
Yes. The code allows an emergency escape opening under a deck or porch if the window opens fully and there is a path at least 36 inches high out to a yard or court. Keep porch posts and framing out of that path.
Does a porch need railings?
Any part of the porch floor that is more than 30 inches above the grade below, measured within 36 inches of its edge, needs a guard at least 36 inches high. Porches close to the ground often go without.
What is the best porch material in wildfire country?
Noncombustible or fire-resistant decking and posts, a metal roof, and the space underneath enclosed with 1/8-inch or smaller metal screen, or kept clear and noncombustible, as the Idaho Department of Lands recommends. Keep cushions, firewood and propane away from the porch.
Can a wrap-around porch be added to a barndominium kit?
Most kits can include porch framing and roof panels, but it is easier to design the porch with the building than to add it later. The eave, the gutter and the porch roof connection are where snow and water decide whether it works.

Want this drawn for your program and your parcel? That is where a build actually starts.

Sources

Code figures on this page are from the 2018 International Residential Code as Idaho adopts and amends it (the Idaho Residential Code), and from Idaho's septic rules as read in September 2026. The code in force when your plans are reviewed governs. Snow load and frost depth are set locally, by the building official where your city or county runs a building program.

  1. University of Idaho — Ground Snow Loads for Idaho, 2015 Edition
  2. ICC — 2018 International Residential Code, Chapter 3 Building Planning
  3. Idaho Department of Lands — Idaho Wildfire Home Protection Zone Evaluation, Homeowner Form
  4. Idaho Firewise — Building Materials

Start your plans

Tell us what you want to build and we will draw this for your program, then confirm what it looks like on your parcel, which office permits it, and a realistic budget range. That conversation costs nothing.