Roofing component
What is a soffit on a house?
Look straight up under the edge of the roof: the surface you see is the soffit, and the little slots in it are where the attic breathes.
Updated September 12, 2026 · Every figure links to its source · Sources
DefinitionComponentAlso called: eave soffit, soffit panel
Soffit — the enclosed underside of any exterior overhanging section of a roof eave, running horizontally from the outer edge (behind the fascia) back to the wall of the house; the NRCA glossary defines it so, and the 2021 IRC, Section R806 treats the vents set into it as the attic's intake ventilation.
What it is
Where the roof overhangs the wall, the rafter tails and the underside of the sheathing would be open to the weather and to every bird and wasp in the county. The soffit closes them. On most houses built since the 1970s it is vinyl or aluminium panel, perforated or slotted for ventilation, snapped into channels at the fascia and the wall; on older and higher-end houses it is wood boards, plywood or fibre-cement, with separate strip or round vents cut in. On a gable end the same treatment under the rake overhang is a rake soffit. Inside the house, "soffit" also means a boxed-in section of ceiling — over kitchen cabinets, say — which is a different thing with the same name.
Ventilation is the soffit's second job. The IRC, Section R806 requires attic vent area and allows up to half of it at the eaves, where the soffit vents are, balanced against exhaust at the ridge; Section R806.3 requires a clear one-inch air space between the insulation and the sheathing at the eave so that the intake is not blocked — the baffles a good insulation job installs.
Why it matters
A sound, vented soffit keeps the eave dry, keeps animals out of the attic and lets the attic breathe. A soffit that has been painted over, stuffed with insulation from inside, or replaced with solid panels quietly turns off the attic's intake, and the ridge vent above it stops working — mould on the sheathing and ice dams in winter are the results. A soffit stained, sagging or dropped is the classic sign of a gutter or drip-edge problem above it, and a hole in a soffit is a squirrel's front door.
The directory's roof ventilation calculator works out how much intake a given attic needs, and the answer is usually more than a few decorative vents provide.
What it costs and who does it
Soffit is priced by the linear foot of eave, with the material, the depth of the overhang, the condition of the framing behind it and whether the fascia is being done at the same time as the variables; adding vents to a solid soffit is priced per vent or per foot of strip vent. Roofing contractors, siding contractors and exterior-trim carpenters all do it, and a roofer is the right call when the drip edge, decking edge or ventilation system is part of the job. The directory's roof repair cost guide explains how eave work is estimated, and its guide to roof repair what a repair visit should cover.
Frequently asked questions
Short answers; the sections above carry the detail and the sources.
What is the difference between a soffit and a fascia?
Should soffits be vented?
Why is my soffit sagging or stained?
Next step
Find a roofer who does this
Soffit repairs are cheap and visible, which makes them a fair test of a contractor. The directory lists roofing contractors by state and city.
Sources
- Roofing glossary — National Roofing Contractors Association (NRCA)
- 2021 International Residential Code, Chapter 8: Roof-Ceiling Construction — International Code Council (ICC)