Overhang area, vented panels, F-channel/trim, fascia and vent NFA sized to code.
Estimates are planning aids, not a professional quote. Double-check quantities and product coverage — and any local code or permit requirements — before you buy.
⚠ This is ladder work at the eave the whole way around the house. Use a stabilizer standoff so the ladder doesn't rest on the fresh fascia, and reposition it instead of over-reaching.
| Siding & Trim | $775–$1,049 |
| Finishing & Sealant | $26–$35 |
| Fasteners & Hardware | $23–$31 |
| Total | $824–$1,114 |
Excludes tools, delivery, tax and permit fees. Labor not included — this is a DIY materials estimate.
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About this calculator
Give the Soffit & Fascia Calculator your building's footprint, overhang width and roof shape, and it works out the whole eave assembly: vented or solid soffit panels in 12 ft courses, F-channel at the wall side, trim at the fascia side, a mitered corner piece at each transition, and fascia board or coil wrap for the full run — plus a cost estimate.
Pick full vented panel, solid panel with round vents, or solid unvented, and it checks your choice against the standard 1/150 (or 1/300) attic-ventilation rule, flagging it if the intake side comes up short — an attic with a ridge vent and no soffit intake just backdrafts its own exhaust. Choose vinyl, aluminum or fiber cement, and aluminum coil wrap over sound existing fascia or a new vinyl or PVC board where the old one has gone soft. This is a retrofit and replacement calculator; for a new-construction roof or gutters, see the Roofing and Gutter calculators instead.
Step by step
A step-by-step walkthrough to go with your plan above. Follow the product instructions and any local code or permit requirements as you work.
Pry off the existing soffit panels and fascia board along the run you're replacing, working carefully so you don't damage the rafter tails or fascia backer behind them.
Check every rafter tail and the fascia backer for rot, soft spots or water staining, and sister or replace anything compromised before covering it back up — new trim over rotten wood just hides the problem.
Run F-channel level along the wall side of the overhang for the full eave and rake length, following your chalk line so the soffit panel sits flat and even.
Cut panels to width and slide them between the F-channel and the fascia-side trim, alternating vented and solid coursing if your plan calls for it rather than full vented panel.
Install the J-channel or trim strip along the fascia edge so it captures the outer edge of every soffit panel and gives the fascia board a clean, finished reveal.
Fit a mitered corner piece at each eave-to-rake or hip transition — these are cut and coped on site, so dry-fit before you commit to a cut.
Bend and fasten aluminum coil over sound existing fascia, or install new board where you've replaced it, keeping the reveal consistent along the whole run.
Cut in round vents if you're using them, then run sealant along the wall-side channel joint, every corner and every panel seam so wind-driven rain can't get behind the assembly.
Equip the job
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Decks & Structures
Answers
Soffit is priced by area: eave run times overhang width, plus rake run times rake overhang width on a gable roof, converted into 12 ft panel courses. Fascia is priced by linear foot along that same total run — both eaves and rakes, since fascia wraps the whole roofline while venting typically only matters at the eaves. This calculator does both conversions from your footprint and overhang depth automatically.
It depends on how your attic is ventilated. If there's a ridge vent or roof vents pulling air out at the top, code wants roughly equal intake area at the soffit — typically sized to 1/150 of the attic floor area (1/300 with a vapor retarder and balanced high/low venting), split between intake and exhaust. This calculator checks your vented-panel or round-vent choice against that target and flags it if the coverage falls short.
F-channel is the receiver at the wall side of the soffit run — it's shaped to also catch a starter row of siding above it if there is one. J-channel (or a fascia-side trim strip) picks up the outer edge where the soffit meets the fascia. Both run the full length of the eave and rake, and both get their own line item since they're different profiles even though they're often the same material.
Yes — coil-wrapping sound wood fascia in aluminum is faster and cheaper than tearing it off and installing new board, and it's the default here. But check the wood underneath first: if the fascia or the rafter tails behind it are soft, delaminated or water-stained, wrapping traps that rot instead of fixing it. Replace with new PVC/composite or fresh lumber wrapped in coil stock instead.
There's no fixed code spacing — round vents are sized to hit a total net-free-area target, not a linear interval — but installers generally keep them at least 16 to 24 inches apart so there's enough solid panel between vents to fasten to. If your required intake area forces vents closer than that, continuous vented panel is the better fit than round vents, which this calculator will flag.
For an average house eave run, DIY materials in vinyl typically land in the several-hundred to low-thousand-dollar range depending on overhang depth, run length and whether you're wrapping or replacing the fascia; aluminum and fiber cement run higher. Labor is a big share of a professional quote because it's all ladder work, so DIY savings are real if you're comfortable working the eave line.