How To Repair Rotted Door Jambs

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Check out our other ROT-RELATED VIDEOS linked below!
Repair Rotted Trim (Skirtboard):
Fix Rotted Brickmold:
Fix Rotted Sink Cabinets:
Replace Deck Handrails:
Fix Rotted Basement Stairs:
Repair Leaning Fences:
Replace Deck Boards:

This video from The Honest Carpenter will show you a COST-SAVING door jamb repair. There are about $10 of materials in this repair, and it can be carried out in 1-2 hours by anybody with reasonable tool experience.

Tools:
Oscillating Multi-Tool
Table Saw
Miter Saw
Chisel:
16 Oz Hammer
Large screwdriver
Combination Square
Brad Nailer/Compressor
Tape Measure
Utility Knife
Caulking Gun

Materials:
Construction Adhesive
Galvanized Brad Nails
Elastomeric Sealant
Treated 5/4 pine
PVC Trim

How-To:
1) Mark lower 12-16" on door jamb with straight line using combination square and pencil.
2) Cut through marked line with oscillating multi-tool.
3) Carefully chisel and break out lower portion of door jamb
4) Measure up from threshold to cut line
5) Rip 5/4 pine to door jamb width
6) Cut new door jamb piece to length, remembering to add 5 degree miter to bottom
7) Install shims to bring door jamb piece out flush
8) Install door jamb piece with construction adhesive and brad nails
9) Caulk new door jamb assembly

For a detailed article on the OSCILLATING MULTI-TOOL used in this video, just click here:

For more tips and articles, visit us at The Honest Carpenter website!

[arthur-rizo]

I called three separate carpenters for estimates on repairing my door jamb (walk in cellar). Both sides were rotted on the outside in the jamb to a height of 24". They all said the entire unit must be replaced (including a door) and quoted me $1200.00-$1450.00. I wasn't born yesterday, I could tell they were thieves. I bought a cheap oscillating multitool for $39.00 at Harbor Freight tools. I took out the weather exposed side cutting it by the door stop. I purchased PVC trim at HD. I'm old so I took my time. Took me about 6 hours of fussing. Total cost was $175.00. I was told it looked better than what a carpenter could do. It will last forever being made of PVC Veranda. So it matched, I did all three sides and used top quality stainless screws. I know I went a bit overboard on framing the door. But it looks so good. I kept the heavy steel door and there was not one bit of rust on it. I originally installed the unit 37 years ago.

[ScottsSynthStuff]

After doing this job three times in 10 years on the same door, I finally ripped all that trim out and replaced it with vinyl. No more painting, no more rotting. Did the same thing for my garage surrounds, for the same reason, with the same result. Looks great, no more rot!

[g.s.]

Thank you for taking the time to put this video together. I had been putting off this job on a couple doors for too long and tackled them today. They look better than new. Before reading the comments, I also made a few modifications that have already been mentioned (45 degree horizontal cut, plunge vertical cut so the old/bad piece comes right out). But watching the video made the job go MUCH faster and problem-free. I realize that the video is 2 years old, but wanted you to know that it is still helping people! Thanks again.

[johnwente]

To make it easier to cut a straight line, tack a guide strip to the lower part of the board. Let the multi-use tool blade rest on the guide strip while cutting. Even someone like me who's hands shake quite a bit can make a straight cut this way.

[KayKay]

Thanks for your video. I repaired a rotte door jam on our outbuilding using these instructions. Worked like a charm and looks professional! My husband was impressed. He said "now I don't have to hire someone." Hell, no, we can do it! Thanks to you!!!!

[vanwin]

75 yr old woman doing this all by myself. And yes i have my own multi oscillating toolq

[artalamoc]

I'm new to doing my own home wood repairs, and for the last 2 months I have seen over fifty videos on door repairs and on this one video I learned a whole lot more. I feel like your in my head knowing all the question I have about this kind of work and you have all the answers, thanks and I have subscribed.

[bobk.]

Additional tip - use the caulking to seal the end grain on the bottom of the piece of wood. Put a small amount on the end grain and rub it in to the wood. Really helps it not rot in the future.

[shmerd]

I might add, a speed square comes in really handy on this repair. Slide it to the location you want your plunge cut and use it as a guide for your oscillating tool.

[olmoe]

You did a pretty good job on this jamb repair....
I've seen jambs rot like this for 4 decades now...and you only had two choices to repair it, either tear out the whole frame, or repair it like you did....
For the past 15 years or so, the Jamb materials have gotten better, and this type of repair should no longer be a problem....If the proper frame is used in the correct location....
I am a Door Builder by trade, , Building both standard and custom Exterior entry units....
And Currently there are 3 types of standard Jamb materials that we use...
Primed fingerjoint pine jambs, Frame saver pine jambs, and Solid composite jambs....

The primed pine jambs should Ideally be installed in locations not exposed to direct weather, like a Garage, a Porch, or location that has a large over

Frame saver jambs are our main sellers, because they pretty much Eliminate the type of rot that you just fixed... these are pine jambs, but the lower 4 inches are made of a Composite material to eliminate water penetration at the Jamb/sill joint...

The all Composite frames are the best, , due to the fact of never having to worry about any rot, , but they are pretty
As the old saying goes.... "You get what you pay for"....

[LexLuthier]

Rather than using a level cut as you did, I use a scarf cut sloping down to the outside so it will shed water. Silicone is not paintable so I use elastomeric caulk (Lexel, e.g.) at the bottom.

[DIMENSIONALCARPENTRY]

Ethan, I always use an old chisel or a sharpened flat trim bar for jobs like you're showing in this video. I find that either of these tools work better than a "demolition" screw driver.

[splash]

Good vid!
Quick tip for you.
The surgical line you speak of...if you want it to disapear, very slightly bevel the existing edge and new edge of the cut line with sand paper. Install your piece, and once adhesive sets up, use some automotive body filler over that area. Sand it flush once dry, and your ready for paint!
You did a nice job, so might aswell take one more step to making it look invisible to the normal eye. The caulking shrinks back and you'll always see that cut line.

[NateGrede]

Used your video to do this today. Was able to find a three foot section of jamb at Home Depot. So didn't have to cut my own groove. I sealed the ends as you suggested which is a good tip even for treated wood. Thanks for putting this together and supporting DIYers.

[howtodoitdude]

I was taught by a professional carpenter to cut in a step pattern rather than cutting straight across. It would lock in better and be more supportive. Thanks for sharing!

[ActionAwesome]

Watched this video a long time ago but remembered it. I just came back to say thank you and tell you this video helped me fix my own issue here on my house. Thank you!!!!

[MrBlaser]

Great work !! From a retired high end custom home builder !!! I have seen these situations a million times !!!

[Xtreme]

Whenever I replace any vertical wood trim I put a 15° bevel aka weather cut instead of making a straight cut. To do this using the same tool you used just cut a 15°bevel on a scrap piece of wood same width as the piece you're removing and tack it to the piece you're cutting off. Short point on the face, using this as a guide for your saw. It will make the joint disappear use a small amount of caulk in the joint. Also leave an 1/8" gap at the bottom of the threshold to allow caulk to adhere to the piece you're installing. I use a nail puller to put upward pressure on the piece while nailing to get the joint tight. Sorry about the long comment but I'm very detailed when making exterior repairs. Hope you give this method a try.

[patricklastname]

Pro handyman here. I used to repair the same way. Will rot again. Clean up, remove rot, fill with foam, glue/nail pvc plank in front as you would a baseboard, silicone/call up to you...done in no time and will never rot again.

[thomasharris]

Here’s a tip I use… When using wood brick mould/jamb make sure your use a primer or paint on the bottom 3 inches BEFORE you install, to help seal it and “help” with future water repelling to assist with rot.