How to Repair Rotted Soffit and Fascia – Part 4

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This project is continued from How to Repair Rotted Soffit and Fascia – Part 3.

With the new soffit and fascia installed, it’s time to rehang the gutter. The gutter was originally fastened with gutter spikes nailed into the rafter tails. Gutter spikes are similar to big nails. The problem with gutter spikes is they tend to work themselves out and become loose.

Gutter Screws versus Gutter Spikes

Gutter Screws versus Gutter Spikes

I used gutter screws to reattach the gutter. Gutter screws won’t back out like smooth spikes and hold better. The gutter screws are on the left and center in the above photo.

Reinstall the Gutter

The old gutter sealant is scraped off the end of the gutter and all dirt is washed off. Do the same for the mating gutter end at the front of the roof.

The corner gutter joint is fastened with aluminum pop rivets: 1/8″ rivets for the face and 3/8″ rivets on the bottom. A pop rivet tool with several head sizes is needed.

Pop Rivets for Joining Gutter Corners

Pop Rivets for Joining Gutter Corners

The gutter is laid on the roof and the corner fastened with pop rivets, observing the original sheet metal folds. It was important to fasten this end first because it established the “high end” for proper slope and water drainage. I haven’t installed the gutter screws yet because this short section of gutter is light, rigid and the far end sits against and is supported by the roof.

Gutter Corner Joint Fastened with Pop Rivets

Gutter Corner Joint Fastened with Pop Rivets

The corner seam of the gutters is sealed with gutter sealant that is applied to the inside of the gutter. Take care to remove the old sealant and dirt before applying sealant from both gutter sections.

Gutter Sealer

Gutter Sealer

Rehang the Gutter with Gutter Screws

Gutter screws are simple to install with a cordless drill/driver. I wasn’t able to get a decent photo working over my head on the 2nd story, though this photo from work I was doing later illustrates the installation. Lift the shingles to double check the screw is aligned with the rafter tail before installing.

Attach the Gutter with Gutter Screws

Attach the Gutter with Gutter Screws

The 11 foot section of gutter was short enough that it didn’t sag with the far end resting on the roof, so it wasn’t necessary to chalk a line to maintain the proper slope. In fact, the slope was an aggressive 3/4″ over the 11 foot length.

A view of the scaffold and re-installed gutter with the new soffit and fascia:

Rotted Soffit Repair: Reattached Gutter with new Soffit and Fascia

Rotted Soffit Repair: Reattached Gutter with new Soffit and Fascia

The soffit joints are caulked with a paintable exterior grade silicone caulk.

Rotted Soffit Repair: New Soffit Plywood and PVC Fascia Board

Rotted Soffit Repair: New Soffit Plywood and PVC Fascia Board

Roof Valley Flashing to Protect the Soffit

The TUF Board PVC fascia won’t rot if it gets wet, however the plywood soffit will eventually rot if it gets wet.

To prevent rain water from leaking under the fascia and onto the soffit again, I slipped a 4″ x 8″ section of flashing under the shingles and over the gutter end at the roof valley to direct the rain water away from the fascia:

Flashing over the Gutter and Roof Valley

Flashing over the Gutter and Roof Valley

I crawled into the attic during two different rainy periods and confirmed the flashing kept the water out. It worked like great.

The roof valley drainage problem onto the soffit was fixed when I later had the roof replaced by re-engineering the entire setup:

  • Install kickout step flashing behind the PVC fascia board to direct any rain water away from the plywood soffit.
    • Other examples of kickout step flashing are here and installation details here.
    • The roofers loosened the PVC fascia board (recall I fastened it with stainless steel wood screws) to insert the kickout flashing behind the fascia board. The flashing, fascia board and soffit seams are then caulked.
  • Install drip edge flashing that extends from the roof deck and over the top of the fascia board.
  • New gutters that stop short of the roof valley so leaves and debris do not catch on the gutter and wash off.
  • Added gutter downspouts to better handle the water flow and drain the gutter away from the roof valley.

This project is concluded in How to Repair Rotted Soffit and Fascia – Part 5.

Thanks for reading,

Bob Jackson

Copyright © 2018   Reproduction strictly prohibited.


  1. Reed April 3, 2014 at 9:01 pm - Reply

    I need to replace some rotted fascia around the corners of my single-story home. I wasn’t sure how to approach the project, but am now feeling confident.
    Well written and informative, with great photos!

  2. Marty Sonders July 14, 2014 at 1:14 pm - Reply

    I usually look for youtube type videos for do-it-yourself help. Your written description and photos were so detailed, however, that they were a tremendous help and learning opportunity.

    Even the setup procedure, with roof brackets and scaffolding, right down to the source, transportation, and cost, was provided. Thanks for all the work you did on this.

    • Bob Jackson July 14, 2014 at 2:31 pm - Reply

      YouTube videos are an excellent resource. I tend to favor high resolution photos in most cases for clarity of detail, concise presentation, detailed descriptions/illustrations and ability to print or save items offline for reference. Producing videos also requires more skill and effort – at least to meet my quality standards.

      Thanks for the compliments!

  3. Laurie August 27, 2014 at 11:19 am - Reply

    Great instruction and photos! I think I can actually do this repair now. Thank you!

  4. Dawn October 16, 2015 at 10:06 pm - Reply

    Hi Bob,
    Thank you so much for this post. I am having a similar problem with rotted soffit. The rot doesn’t seem very extensive (about 6-8 inches from the shingles). Typically how much soffit should be replaced. For the area you repaired how much should the average cost be with material and labor?

    • Bob Jackson October 17, 2015 at 5:37 pm - Reply

      The soffit is typically plywood or maybe HardieSoffit cement board. Let’s assume your home has plywood soffits. The material cost isn’t much to replace a section of soffit – general estimate:
      * $17 for an 8 ft x 4 ft x 3/8 in sheet of sanded plywood (use the same thickness as the original soffit)
      * $6 Silicone paintable caulk
      * $9 box of 100 wood screws (far fewer than 100 are needed)
      * $45 exterior latex paint
      $77 total materials w/o tax

      The rest of the cost is labor: purchase and transport materials, remove the rotted section, measure, saw, install the new soffit panel, caulk and paint. If the soffit is in a high and difficult location the repair person will likely charge extra especially if the roof is steep and can’t be walked on. My guess is labor will run in the $200 to $250 range if it’s a single story high soffit with easy access. There are home repair cost calculator websites that provide estimates for various repairs and renovations, do a Google search for “home repair costs estimator”. Your mileage may vary. I suggest hiring only someone listed with the Better Business Bureau with an A+ rating. Obtain a detailed written quote and never sign anything in advance.

      > Typically how much soffit should be replaced.
      “In for a penny, in for a pound.” The cost will be nearly identical to replace 8 inches of rotted soffit as the entire panel. Plywood soffits are typically 8 feet long (if no corners or walls are present) because it was ripped from an 8 feet sheet of plywood. May as well replace the entire panel.

  5. Brenda May 1, 2016 at 1:52 am - Reply

    Hi Bob, I was thinking about using 1/2″ cellular PVC for the “soffits” as well as the fascia boards and would value your opinion about this option. We have a 35ft straight run along our sunroom. The rafters are 24″ apart, according to my research on PVC boards/Sheets I will have to add 2×4’s in between the rafters, crossway as they call for a 16″ nailing pattern to accommodate any expansion. Since I would like to do this job myself installing the PVC sheets seem to be the easiest.
    Thank you

    • Bob Jackson May 1, 2016 at 12:58 pm - Reply

      Hi Brenda,
      You’re going about it the correct way. Various PVC vented soffit panels are available, check with your local lumber supply if it’s not available in the big box home improvement stores.

      I prefer PVC trim boards, mouldings and soffits because it won’t rot, doesn’t need painting, saws like wood and insects won’t attack it. Cement board Hardiesoffit is really good too but it’s heavy, creates a lot cement dust when sawing and a pneumatic nail gun is strongly recommended to avoid busting a divot on the backside of the board.

  6. William April 11, 2018 at 10:34 pm - Reply

    Hey Bob, I’ve got about six inches of rotten soffit, which is next to a vent. I was think about cutting a short piece of plywood perhaps 20 – 24″ long using plywood of the same thickness that’s on it now. What say?

    • Bob Jackson April 12, 2018 at 8:01 am - Reply

      The soffit repair panel should span at least 3 lookouts for support. Since you’ll need to buy an 8 foot sheet of plywood and rip it to the needed width, why not replace the entire section of old soffit? A new 8 foot panel will evenly span lookouts on 16 or 24 inch centers for little extra effort.

  7. Joyce November 17, 2018 at 7:47 am - Reply

    Wow I read all of it. Great instructions the corner wood behind screwed gutter (trim) first time was a petrified wood piece all dust needs replacement (PVC) & need two pieces wood short length attached to each side of rafters. Gutter repair at closed end corner. Work with ladder & a handy man. I like to know what needs to be done. Had to scrub soffit with brush and wet cloths. Thanks

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