The eaves are the roof edges, where the roof extends out past the exterior walls of the house. Eaves are ideally covered with soffit and fascia boards.
Fascia is a 4-8 inch high vertical band of material that covers the forward-facing edge of the eave. On some homes, this forward-facing band of wood is simply covered with paint. However, on most to today’s homes, that edge is covered with material called fascia. Fascia covers the wood and protects it from water damage. If the wood along your roof line is damaged by water, the rot can spread to your roof and make your roof vulnerable to leaks or pests.
The roof also hangs over the edge of the home by a foot or more, leaving a horizontal area under the roof edge. If this underside of the roof overhang is left unfinished, you will see beams, roof decking and open space leading into your home’s attic. Soffits are boards that cover that horizontal underside of the roof edge.
Older houses, or less expensive houses, may not have soffits or fascia. Some people think that soffits and fascia are unnecessary and may try to save money by not including them on their new homes. But the soffits and fascia cover of the edge of the roof and give your home a more finished look and also helps keep out pests like bats, birds and squirrels. And building codes in your region may require fascia and soffit boards.
Soffits, like fascia, can also help protect your house from moisture damage. If, for example, you’re building in an area that has high winds that can drive rain under the eaves, your soffits help to keep water from getting into the internal structure of the house.
Ok, to help us remember: Soffits are the soil- or sidewalk-facing portion of the eave and fascia is the forward-facing portion of the eave.
Fascia boards do not need to be vented. In fact, fascia perforations for ventilation would actually let water come in contact with the underlying wood and that would contribute to rot and decay of the wood beneath the fascia.
Soffits, on the other hand, can be vented or unvented. Usually vented soffits are paired with vented roofs and unvented soffits what you use for unvented roofs.
Whether you choose a vented roof and vented soffits, or an unvented roof and unvented, solid soffits will depend on several things, most importantly the code requirements in your area. But also your climate, your personal design preferences and your building envelope.
It’s my understanding that a tight building envelope with a conditioned attic space and insulation on the roof decking, means there will typically be an unvented roof and unvented soffits. But check your building code, and consult your builder or roofer, your home energy rater and/or your soffit and fascia contractor for their recommendations. In many regions, there are contractors specifically for soffit and fascia installation.
Now, let’s talk about the materials that can be used for soffits and fascia. Soffits and fascia can be constructed from aluminum,, vinyl, sheet metal, wood and synthetic and composite materials like UPVC and fiber cement.
Vinyl is one of the most affordable choices. Vinyl is a good insulator and It won’t rot, crack or chip, but it can develop mold in very moist areas. Some vinyl can fade over time. Vinyl is not as flexible, and harder to cut than aluminum. Vinyl is not very durable and some people think vinyl looks inexpensive and not as attractive as other options
Aluminum soffits and fascia are durable. Aluminum is flexible so it can be put into oddly shaped spaces. Aluminum is water-resistant and won’t rot, chip or crack. It’s easy to keep clean and does not attract dirt. Some builders prefer aluminum over vinyl because aluminum is flexible and can completely encapsulate the fascial surface (better than vinyl). The downsides of aluminum are that it is more expensive than vinyl, it can dent if enough force is applied, and it does not insulate as well as vinyl.
Sheet metal, like steel, is one of the most durable options on the market and it comes in numerous colors, but it’s expensive and it can rust. Some sheet metal boards can look too rustic and old-fashioned for some homeowners’ tastes.
Composite boards are expensive but very durable. Composite soffits and fascia are color-fast and resistant to rot and decay. Repairing composite fascia and soffits can be difficult. The cost of using composite lumber for fascia and soffits can be twice that of other materials, but its long-term durability make it worth the expense for many homeowners.
Wood is a beautiful option that can added for either a rustic, or more contemporary look, but wood needs to be restained and resealed, or repainted multiple times over the life of the home. Wood soffits and fascia will have a shorter life span than other materials, even with proper maintenance. But cedar is naturally weather-resistant, especially when it's stained or painted.
Fiber cement is a less common, pricier option in soffits and fascia, but suppliers carry fiber cement panels with various wood grain textures, vent patterns and colors.
If you are using aluminum, vinyl or fiber cement siding on your house, most people go with the easiest design choice, and simply use the same color (or white) and the same material on their soffits and fascia. That way, you have a matching material that keeps the continuity of the siding.
Fascia and soffit are considered trim materials and the style and color you choose can have a big impact on the overall look of your home. White is standard color for soffits and fascia, but you can buy them in a variety of colors, or some of the white materials can be painted. Synthetic fascia and soffit materials can have a smooth finish or have a texture that mimics wood grain.
There are lots of choices out there. You should obviously choose colors and materials that will complement your home’s overall look and fit into budget and your desired level of maintenance. And if you are tempted to forgo your soffits and fascia for budgetary reasons, don’t. They are too important in protecting your home from moisture and pests.
Well, that’s all I have for you this week. I hope you learned as much as I did. And I hope you'll join me next week for another episode of Build Your House Yourself University--BYHYU.
Please remember that the purpose of this podcast is simply to educate and inform. It is not a substitute for professional advice. The information that you hear is based the only on the opinions, research and experiences of my guests and myself. That information might be incomplete and it’s subject to change, so it may not apply to your project. In addition, building codes and requirements vary from region to region, so always consult a professional about specific recommendations for your home.