Doing the job yourself can save a lot of money, because adding aluminum soffit is much more labor-intensive than material-intensive. You should be able to find all the materials that you need at most large home center stores. The aluminum soffit material is usually available in white and brown colors.
Since you will be saving so much on the labor costs, it might make sense for you to buy a higher-quality (and more expensive) aluminum soffit material at a professional roofing outlet. This material usually uses heavier-gauge aluminum. Although the strength of the material is not important for it to function properly, a heavier-gauge piece is stiffer and often easier to work with for most do-it-yourselfers.
Before actually starting this project, make sure that your roof is in good condition. If you or your painter used proper preparation and good-quality paint last time, the soffit should not need painting as often as every two years.
Installing aluminum soffit over the old wood soffit will only hide a roofing problem temporarily. If there are water leakage problems, the wood hidden behind the aluminum will be destroyed over time. Have your roof inspected and any roofing repairs made first.
The fascia, the piece of wood that connects the soffit to the underside of the shingles, is usually covered with aluminum at the same time for a finished look.
To replace the fascia, you will have to remove the gutters. This task requires a helper so that you can reuse the old gutters. Old gutters come loose easily, so little strength is needed. The helper is needed more to support the gutters as you remove them so that they are not damaged.
For most homes, it is best to select vented aluminum soffit material. It is perforated with thousands of tiny holes (too small for most insects to enter) to let air flow through. This air enters your attic lower over the insulation and naturally exhausts out vents at or near the peak of the roof. It is essential to have attic ventilation year-round.
If your house has existing attic vents, you should remove the covers so that the aluminum soffit will lay properly against the old soffit. If not, saw holes in the soffit to provide an air path into the attic area.
Cut and evenly space enough holes to provide about 1 square foot of open vent area for each 300 square feet of attic floor area. You may have to nail wood baffles in the attic to keep the insulation from blocking the openings.
You can find many books and pamphlets at home center stores describing the exact details of how to cut and attach the soffit and fascia, but here is a short summary.
A J-channel is nailed to the existing soffit against the house wall. One edge of the aluminum soffit is slipped into and secured by the J-strip. Each piece of soffit is cut to reach from the J-channel to just inside the outer soffit edge. This outer edge is nailed to the soffit with matching nails. Stronger stainless steel nails are best to use for do-it-yourselfers. The fascia material is added over the edge and the gutters are reattached.
