Soffit and Fascia in St. Louis

What soffit and fascia do, and how they fail

The fascia caps the rafter ends and gives the gutters something to hang on. The soffit closes the gap between the fascia and the wall, and on most houses it is also where the attic takes in air. Trouble shows up in a few familiar ways:

• Soft or split fascia behind the gutter. Water that runs behind the gutter, or over it in a heavy rain, soaks the board where nobody can see it. By the time the paint lifts, the wood under it is often punky.
• Sagging or loose soffit. Long runs need backing. The vinyl manual calls for nailing strips when the eave is more than 16 inches deep, and panels hung without them droop.
• Stained or blocked vents. Insulation pushed into the eave, paint over vent slots or a solid panel put up where a vented one belongs all starve the attic of air.
• Gaps at the corners. Where the eave meets the rake, the corner the trade calls the bird box is the usual way in for birds, squirrels and bats.

A rotted fascia is rarely only a fascia problem. Push on the rafter tails and the sub-fascia behind it before anyone prices a wrap.

Vented soffit and the attic ventilation rule

The residential code's roof ventilation section, R806, sets the air an attic must get. The baseline is net free vent area equal to 1/150 of the attic floor area. The code lets that drop to 1/300 when 40 to 50 percent of the vent area is up near the peak (measured down from the ridge, 3 feet at most), with the balance in the eaves. Every vent opening has to be between 1/16 and 1/4 inch at its smallest, or be screened to that size, so insects and animals stay out.

Two practical rules follow for the eaves:

• The vents only count if air can get past them. The same section requires a 1-inch space between the insulation and the roof deck at each eave vent, which is what the cardboard or foam baffles in the rafter bays are for.
• Net free area comes from the panel maker. Vented soffit carries a net free area rating from its manufacturer, and the vinyl manual says to work from that figure, not a guess.

Which code edition applies depends on your town; the energy code guide and each town page list them.

Vinyl, aluminum or wood at the eaves

• Vinyl soffit. Panels run from the wall to the fascia, much like vertical siding, and come solid, vented or as a mix. They sit in receiving channels and are left free to move, the same way vinyl siding is hung. See vinyl siding for how the material behaves in a St. Louis summer.
• Aluminum fascia cover. Prefinished aluminum, bent to fit or bought formed, wraps the wood fascia so it never needs paint again. The wood behind it still has to be sound, because the cover is nailed into it and hides whatever is underneath.
• Painted wood. Still right on some older and historic houses. It needs paint on a schedule, and the bottom edge of the fascia is where it goes first.

Local rules can decide this for you. Town and Country's architectural review standards prohibit vinyl siding and vinyl soffits (Town and Country). In a City of St. Louis historic district, nearly any outside change needs a Cultural Resources Office permit (repainting wood trim is the one exception), so a switch from wood to vinyl or aluminum at the eaves is a reviewed change (historic districts).

How a soffit and fascia job goes

1. Open and probe. Pull a section, check the fascia, sub-fascia and rafter tails, and look for insulation packed into the eave.
2. Fix the wood. Rotted fascia board is replaced, not wrapped. The vinyl manual is direct about the soffit: if the existing soffit is rotted or damaged, take it out completely before the new soffit goes in.
3. Set the channels. Receiving channels go along the wall and the fascia, nailed every 8 to 12 inches and never driven tight. Deep eaves get nailing strips.
4. Hang the soffit. Each panel is cut to the wall-to-fascia distance less 1/2 inch so it can expand, with 1/4 inch left at turned corners.
5. Cover the fascia. The cover slides into trim or tucks behind the existing drip edge and is fastened along its bottom leg at no more than 24 inches on center, with aluminum or stainless trim nails through pre-drilled holes. Joints overlap 3/4 inch.
6. Close the corners. The bird box at each eave-and-rake corner gets aluminum trim.

On a re-side, all of this happens before the top course of siding goes on, which is the main reason to do the eaves and the walls in one job.

Bats, birds and squirrels at the eaves

Gaps at the fascia, soffit and bird box are how animals get into a roof edge. Sealing them is part of the job, but bats come with rules in Missouri.

• Bats are protected. The Missouri Department of Conservation says all bats are protected under the Wildlife Code of Missouri; nine species are of conservation concern and three are state endangered.
• Timing matters. Young bats may be in the roost in May, June or July depending on the species, and the Department says to wait until they can leave with the adults. Seal an eave too early and they are trapped inside.
• Let them out, then close it. The Department's method is a 12-inch square of heavy cloth tacked over each opening along its top edge only, so bats can push out but not find the way back in. After two or three days with no bats, the opening is repaired. Larger vents and louvers get 1/4-inch hardware cloth.

Birds and squirrels need no waiting period in the same way, but check for an active nest before a section of soffit comes down.

Older houses: paint on the trim

On a house built before 1978, the fascia and soffit are often the most heavily painted wood on it, and the federal lead rule covers paid work that disturbs those painted surfaces. Outside, the small-job exception stops at 20 square feet, and tearing off painted wood counts as demolition of a painted surface, which that exception does not cover. A full run of fascia passes 20 square feet quickly.

Wrapping sound painted fascia with aluminum disturbs less paint than tearing it off, but scraping loose paint or cutting the board still counts. What the rule asks of the contractor, and what you are owed before work starts, is on the lead paint rule page. How common this is varies a great deal by town: most homes in St. Louis City are pre-war, while most in Wentzville were built since 2000.

Permits and local rules at the eaves

Soffit and fascia work usually rides under the same permit rule as siding, and that rule changes at each city limit:

• University City needs no permit for new pre-finished metal or vinyl put up over the walls, soffit, fascia and overhangs already there, as long as no wall opening is made bigger or moved (University City).
• Unincorporated St. Louis County lets you re-side without a permit but requires one to repair damage from wind, fire, flood, termites or an earthquake, however small (county rules).
• Town and Country bars vinyl soffit outright, and historic districts in several towns review visible exterior changes.

Every other town's answer is on its own page; permits by city puts them side by side.

What moves the price of soffit and fascia

We do not publish a price for eave work, because the cost turns on things nobody can see from the street. What moves it:

• Length and depth. Linear feet of eave and rake, and how deep the overhang is; deep eaves need nailing strips.
• Height and access. A one-story ranch is quick; a two-story wall over a slope or a roof below is not.
• Rot. Replacing fascia board, sub-fascia or rafter tails is the item that swings a quote most, which is why it is priced before you sign, not discovered after.
• Vents. Switching to vented soffit can mean cutting openings and adding baffles.
• Older paint. Lead-safe setup and cleanup on a pre-1978 house.
• Anything hung on the fascia. Gutters, lights and cables come off for the board to be replaced.

The free estimate covers the walk-around, the probe of the fascia and rafter tails, the vent check and your town's rules, and you get the scope in writing.

Common questions about soffit and fascia in St. Louis

Where we work

Soffit and fascia across greater St. Louis, from the city and St. Louis County out to St. Charles, Jefferson and Franklin Counties and across the river into the Metro East. Each city has its own page with the permit rule and code edition that apply there: