Fascia boards are one of most common areas for rot on a house. Their position just below the roofline makes them highly susceptible to water penetration. Once the boards become soaked, they quickly begin to deteriorate.

This article gives you an overview on how to carry out fascia board replacements. But, if you tackle this repair, please take all safety precautions! Fasciais high off the ground, and most of the work will have to be done from a ladder.


Tool List:

Speed Square

Nail Puller (Nippers)

6-in-1 Painter’s Tool

Tape Measure

Utility Knife 2-pack

Best Picks:

Makita is always my preferred MAGNESIUM CIRCULAR SAW.

I like a CAT’S PAW TOOL with a sharp. jaw, and this one fits the bill.

This Estwing 16 oz Hammer is the only hammer with a perfect review score.

Note from Ethan’s Dad: For 30 years, I used fiberglass-handled framing hammers. Here is a steal on one from Irwin.

Material List:

Trim Lumber (match existing–or better yet, use PVC!)

2″ Spiral Shank Nails

Siliconized Latex Caulk

Exterior Primer

Step 1. Determine That You Actually Have Rot

wood rot on brick mould

Badly rotted window brickmould

Rot and simple discoloration are two different things. In some cases, spillover from the roof or a gutter just gunks up a fascia board.

Actual rot will show up as soft spots or dark cavities in the surface of the board. (Like the one pictured above). Wood in these places will be mushy and pulpy. To test an area that you’re unsure of, use the steps in this Q&A I wrote about rot testing.

If you’re positive than an area is rotted, next identify where the water came from.

Step 2. Identify The Water Source

new fascia with gutter after wood rot repair

An example of fascia/gutters

In order to carry out an effective fascia repair, you first identify why your fascia got wet. When you have, make repairs to prevent water from soaking this area in the future.

Chipped or damaged shingles can be a common source of water reaching fascia. Look at the lowest course of shingles on your house.

Are shingles damaged at your roof edge? If so, have them replaced. Also consider having your roofer add a drip edge to your house. This metal strip sits under the bottom shingles. It’s designed to make water fall into your gutters. That way, the water doesn’t dribble down behind the gutter and onto the fascia boards.

About those gutters

Gutters are a common source of dampness of the fascia boards. If gutters don’t channel water properly, they spill water back towards the house. Primarily, this happens when they are clogged with leaves.

Have your gutters cleaned regularly. If your gutters still fill up or spill water in odd places, you might want to consider having a gutter expert rehang them. Adding more downspouts to long runs can help this problem. (Here’s a good article on proper gutter hanging.)

Once you’ve identified and fixed the source of your excess water, you’re ready to replace your fascia boards.

Step 3. Remove The Rotted Fascia Board

cut caulk line with utility knife

Cut the caulk line with a utility knife.

To start this project, use a utility knife to cut all seams and caulk lines around the pieces that you want to replace. This ensures that the rotted fascia board comes away without pulling any other components with it.

Use a six-in-one painter’s tool to pry the board away gently at the base. Incrementally work your way across the board in small increments. Avoid prying too hard, too fast.

pry fascia with painters tool

Drive a painters tool into the crack to start your pull.

When you have worked a gap between the boards, switch to a hammer to pry. Don’t damage other trim in the area! Hammers can bruise wood easily.

Pro tip

The key in all trim removals is to be gentle. Don’t make more work for yourself by damaging nearby materials with too much force.

To get boards to come away smoothly, pull the nails holding them in. First, use a “cat’s paw tool” to gouge out and expose the nail heads.

(I’m using one here to free the board from a custom aluminum flashing cap. I’ll nail it back onto my new board.)

pull nail with cat's paw tool

Pull nails with a cat’s paw tool.

Only replacing a portion of a fascia board?

If you only want to replace a portion of a fascia board, make controlled cuts on the trim face with a oscillating multi-tool. I wrote an article on this topic. Click to see how this miraculous oscillating tool works, and how you can use it to interrupt-cut trim.

Or replacing the  whole board?

It’s best to try to remove an old board in one piece—it can come in handy later. However, if you can’t get the full board out, try splitting it with your hammer, and pulling it out in narrower sticks.

Step 4. Examine The Sub-fascia

If the sub-fascia is rotted

When you finally manage to pull your fascia board loose, take a moment to examine the framing lumber that you’ve exposed.

wood rot on sub fascia

That’s some badly rotted framing!

If the untreated lumber is badly rotted (as it is in the picture above), reframe it before you put the new fascia board on.

In general, reframe the area exactly the way it was framed originally. Do this by adding “scab” blocks to undamaged framing in the roof structure. Make sure everything you add is firmly attached and solid. And that the sub-fascia sits flush and level across the entire run.

If the sub-fascia is in good shape

If the sub-fascia is in decent shape, clean it in preparation for mounting the new board. Remove caulk lines and paint globs with a six-in-one tool. (This includes scraping old caulk at the seam of any neighboring boards.)

scrape caulk with painter's tool

Scrape any old caulk from surfaces.

Also remove any fasteners that are still sticking out of the sub-fascia. These leftover nails will prevent your new board from sitting properly.

Simply drive down exposed nail heads with your hammer. If the angle is too awkward, though, or the fastener is bent, back it out with a nail puller instead.

pry nail with nail puller

Using a nail puller (nippers) to remove any remaining nails.

Take a moment and really examine the area. Make sure it is completely clean of any obstructions. It’s frustrating to find that something is preventing your new fascia board from sitting flat.

Step 5. Measure For Your New Piece

The easiest way to do this is to simply measure the piece that you tore off. If the old piece fit very well, use it as a pattern for the new board.

However, if you’ve destroyed the old board in removal, then it’s necessary to measure and plot cuts for a new board.

Producing a new piece can be a little tricky, because fascia wraps around a house. Pieces don’t just need to be the right length. They also need to be the right shape.

Complicated fascia board shapes

Some boards have miter cuts on both ends. Some even have compound cuts where fascia turns up a roofline. Always visualize what you need the new piece to do. Maybe it needs a square cut on one end and a miter cut on the other end. (The one I replaced on this project did.) In any case, fix the image in your mind.

What I had to do

To measure for my new board, I simply butt my tape measure to the inside corner. Then I pulled to the farthest point of the outside corner. This total measure will give me the distance to the long point of my miter cut.

measure for new fascia board with tape measure

Pulling a measurement to an outside corner

Step 6. Cut The New Fascia Board

The most important thing to note here is that you should always replace fascia boards with PVC materials. These plastic-vinyl boards are impervious to rot. For water-sensitive places like fascia, PVC is the best option.

If you want to use wood, make sure you’re at least using quality lumber. Try to get clear pine, as opposed to knotty pine. And don’t use any board that has finger joints—they’ll fail more quickly over time.

Also, get PVC or lumber that matches the thickness (probably ¾”) and width of your fascia board. (You can rip boards down to proper width with a circular saw or table saw if necessary.)

Making the cut

To make your cut, just lay out your required measurement and mark it with a V-shaped pencil mark (“crow’s foot”). Use a speed square to draw a straight line through you’re the point of your mark.

pull measurement on new board with tape measure and speed square

Pull your measurement and draw a straight line, using a speed square.

Again, always keep in mind what face of the board your looking at. If there is a miter cut on your new piece, consider that there will be a short point of the cut, and a long point.

Using a miter saw for your cut is easiest. That’s because you can lay the blade down to 45° for your cut and press the board back to the fence.

A circular saw has a very similar capacity, though. Just unlock and swivel the sole plate to your desired angle. You can use your speed square as a straight edge to guide your saw as you cut. (Just be sure to hold your speed square firmly! Don’t let it wander.)

cut fascia with circular saw and speed square

Carefully cut on the correct side of your pencil line. Let the waste fall away. When the cut is finished, pull a measurement on your board to make sure the length is accurate.

Step 7. Attach The New Board

set new fascia board with nail

I like to take the board up for a quick test fit before I attach it. But first, I’ll half-drive one nail into the board—a little carpenter’s trick that might help later.

A note about nails

Always use galvanized, exterior-grade nails for exterior trim. I like to use 2” spiral shank nails for fascia boards. They’re long enough to reach through the fascia and most of the sub-fascia. Plus, the spiral gives the nail a very firm grip in the wood.

Fasten your new board

Hold your new board in place against your sub-fascia. Examine the seams where it meets other boards. Have someone on the ground do it for you if the board is long.

Small gaps of 1/8” are totally tolerable here. I like to have my fascia boards just a little short—it lets me caulk the gap for better water seal.

If the board is a little long, take it back to the ground and trim it. However, if the board fits, your half-embedded nail comes in handy here. Just drive it to lock the board in place. You can now add the rest of your fasteners.

Fascia boards have very little pressure on them. There’s no need to go overboard with fasteners.

A high nail and low nail every couple feet is all it takes to secure the board in place. (Just make sure you’re fasteners are sinking firmly into the sub-fascia behind the board.)

8. Caulk Everything

caulk new fascia board

Caulk all joints, seams, and corners.

This is a straightforward procedure. Cut the tip of your caulk tube to allow about a 1/8” flow. Squeeze and smooth beads at all seams and junctures. Be sure you’re using siliconized latex caulk for exterior applications!

Also, drive your fasteners slightly past the surface of the fascia with a hammer and nail set. Caulk these divots to hide the nail heads.

After a little dry time, you’re ready for a couple of coats of exterior paint. If you removed gutters, rehang them. You’re all finished!


new fascia in place after wood rot repair

The new fascia looks great!

There are, of course, a thousand variations on this repair. For instance, not all fascia will look like the one I’ve fixed above, which is a decorative double fascia.

Many fascia boards hang down in open space, creating the “eaves” of the house. These eaves often enclose a suspended “soffit”—a thin board that hides the rafter tails.

fascia repair and hardie plank soffit repair

If your soffit is rotted, you’ll need to replace runs of that as well. This is a slightly more involved procedure, but also not too difficult.

If you’re soffit isn’t rotted, though, your repair will be much like the one I’ve depicted. Remember to remove old material gently. And, of course, PLEASE BE SAFE!


If you have any questions, or if you have a suggestion for a subject of a future blogpost, please go to our Contact page. Thanks!!