Fascia boards and roof sheathing are inconspicuous elements of a home’s exterior, so it can be tempting to pay no mind to how they should be installed.
If you take time out to study an unfinished roofing structure, you’ll see that fascia boards go directly under the roof sheathing. What you might not be able to figure out is which roofing material goes before which.
It is widely held that fascia boards and other roofing materials can be installed in any order, but this is false.
In this article, we will discuss the correct order of installing roofing materials like fascia boards and roof sheathing and several mistakes to avoid along the way.
Here’s if Fascia Board Goes Under Roof Sheathing:
Fascia boards must always go under the roof sheathing, but not in a way that the sheathing projects over the fascia boards. Wrong fascia board or sheathing placement can lead to serious issues with a building’s structure and exposes a building to deteriorative external elements or conditions.
What Comes First Roof or Fascia?
Many components make up a roof. Some roofing parts are put in place before the fascia is installed, while others go up after the placement of the fascia. So, the question of what comes first between a roof and fascia isn’t so straightforward to answer.
A roof consists of wooden frames called joists, rafters, gable studs, collar ties, and trusses. These components give a roof strength, stability, and shape.
Decking or sheathing goes on top of the wooden framing, followed by underlayment, shingles, and the ridge; these structures altogether make up what we all know as a roof.
Now you might be wondering, where does the fascia board come in in all this?
The fascia board comes in when the framing is in place. It is typically nailed to the end of the rafters or the rafter tails. So, it’s the building material that you install somewhat in the middle of the roof construction.
As you must’ve figured out, the roof sheathing or decking is to be installed after the fascia board is nailed in place, then the underlayment, shingles, and ridge.
Kindly note that before a fascia board is installed, tail cuts must be made to the end of the rafters. The purpose of these cuts is to ensure that the fascia board stays on straight.
A slanting fascia board over a straight wall is usually a major indicator that your rafter tails do not align, either because you made uneven cuts or didn’t make any cuts at all.
Should Roof Sheathing Overlap Fascia Board?
If there’s one thing you can’t afford to get wrong when constructing a roof, it’s the placement of the sheathing or decking. Even weight distribution across a roof cannot be achieved without this roofing material properly in place.
With that said, let’s take a look at how sheathing and roofing materials like fascia boards should be placed during the construction of a roof.
Roof sheathing or decking should never project completely or partially over a fascia board. So, sheathing that overlaps a fascia board is a big no-no.
The only roofing component the sheathing or decking is allowed to overlap is the rafter tails, but the overlap should be the exact width of your fascia board.
Another way the sheathing of a roof can be placed is flush with the rafter tails. In this position, the sheathing neither projects nor falls behind the tails.
In a nutshell, roof sheathing can be placed on top of a fascia board to align completely with it or behind a fascia board to meet and align with its inner edge.
Never place a roof decking or sheathing in a position where it projects over the fascia board.
Should Fascia Be Installed Before Shingles?
As you may know, shingles are decorative and protective roof claddings. They can be made of a wide variety of materials. The order in which you install fascia and shingles depends on the state of your roofing structure.
For instance, if your roofing structure is at the early stages of construction, you must install the fascia before the shingles.
To be more precise, you should install the fascia first, then your roof decking, underlayment, and finally shingles.
The only time you’re permitted to install shingles before a fascia board is when you’re replacing both of these exterior add-ons on an old or existing roofing structure.
Kindly note that it is not a good practice to install a new layer of shingles over an old layer; this would add more weight than necessary to your roof.
This approach is especially dangerous if there are two layers of shingles in place.
According to state or local building codes, no more than two layers of shingles are permitted on a roof.
Additionally, fascia boards have covers that can be installed at any point in time.
Five Mistakes to Avoid When Installing Fascia Board
When installing fascia boards, roofers must pay attention to details and avoid some common mistakes usually made when installing fascia.
You as a homeowner should also be conversant with these mistakes so that when supervising construction works in your home, you can know the details to pay attention to and things that should be avoided.
Here are five mistakes to avoid when installing fascia boards:
- Not Checking the Quality of the Materials
It is important to check through every material you will use for your fascia board, especially if they were ordered online. DIYers commonly make the mistake of assuming that all materials are of top-notch quality.
Thoroughly examine your fascia board for cracks, cheap paint, and other defects before proceeding to install it.
- Renovating During the Wrong Season
When planning renovation or construction work, ensure it’s around a time of the year with favorable weather. Certain weather conditions especially the ones characterized by heavy winds can increase the complexity of your job.
- Not Handling the Fascia Cover With Care
Fascia boards are usually covered with aluminum panels to protect them from degradation or damage.
Never remove the fascia covers when carrying out modifications of other parts of your roofing structure unless the covers are getting in the way of your work.
- Neglecting the Orientation of the Gutter
It is a common mistake among roofers to think that the position of the fascia board has nothing to do with the orientation of the gutter.
Often times, the orientation of your roof gutters is dependent on the position of your fascia board.
- Attempting to Fix Your Fascia Board Yourself
Only experienced DIYers should attempt to replace or install a fascia board because working at such a great height can be quite dangerous.
If you’re an experienced DIYer and not used to working at great heights, please contact a professional to carry out your fascia board replacement or installation.
Summary
When installing fascia boards and roof sheathing always remember that the first comes before the latter in order of installation and that the latter should never project over or overlap the first.
As long as you keep in mind the above pointers your installation should go pretty smoothly.
We have lots of articles that cover various aspects of roofing structures incase you need more information on this area of home improvement.
sacramentohandyman.com/blog/fascia-and-soffit-installation-what-you-need-to-know/
fotolog.com/what-goes-on-first-fascia-or-soffit/
whoatwherewhy.com/does-sheathing-go-over-fascia/
iko.com/na/pro/building-professional-tools/roofing-101/roof-fascia-repair-replacement/
raincalcining.com/2019/08/21/top-mistakes-that-roofers-should-avoid-when-installing-fascia-covers/
alliancetrustaluminum.ca/fascia-installation-6-mistakes-need-avoid/
