Repair or replace door?

[julian abram]

Sorry, this is not a real woodworking question but not really too much off topic. This is an exterior fiberglass patio door that the bottom 6" has decayed. The door is still in nice condition other than this decayed area. I'm trying to figure out if I should repair this or just replace it. To repair I thought about machining a piece of pressure treated pine to fill in the rotted out cavity. I think there are some exterior wood fillers on the market that are used in porch repairs on columns and rails. How would you repair this? Sorry for photo being sideways.
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[Ronald Blue]

This isn't my area of expertise but that doesn't look like fiberglass to me. It looks like an ordinary wood door to me. Fiberglass wouldn't rot. It supposed to be very durable which is one of it's benefits.

[Andrew Hughes]

I would make a new door if I thought I could make a better one.
If I didn’t or didn’t have the time repair for sure.
If you make a new maybe you could use the glass and hinges knobs ?

Good Luck

[Mel Fulks]

Yes, I would NOT buy another door. I would dry it our with a hair dryer. Chisel down to undamaged wood. Use hair dryer
again. Make a loose fitting block of wood to fit. Epoxy inthe new block. If you have some copper naphthanate,paint in on
the final wood surface. Let it dry couple days. Prime and paint.

[Frederick Skelly]

Yes, I would NOT buy another door. I would dry it our with a hair dryer. Chisel down to undamaged wood. Use hair dryer
again. Make a loose fitting block of wood to fit. Epoxy inthe new block. If you have some copper naphthanate,paint in on
the final wood surface. Let it dry couple days. Prime and paint.

+1. .......

[johnny means]

What is that going on with the door's skin? If that damage extends beyond that corner, I wouldn't bother with a repair.

[Ray Newman]

Believe that Mel Fulks is on to it!

[julian abram]

This isn't my area of expertise but that doesn't look like fiberglass to me. It looks like an ordinary wood door to me. Fiberglass wouldn't rot. It supposed to be very durable which is one of it's benefits.

I didn't explain the construction of this door very well on the opening post. In Lowe's or Home Depot you will see a hundred of these type exterior doors with either steel or fiberglass skins. This one is fiberglass skin with a Styrofoam core, and about 2" soft wood frame around the outside. I dug the rotten wood all the way down to the foam core.

[julian abram]

What is that going on with the door's skin? If that damage extends beyond that corner, I wouldn't bother with a repair.

The skin is fine, just dirty.

[Tom Bender]

Last summer I took my exterior doors to the shop one at a time and repaired as needed and repainted. Good to go for many years more. Would not have been very successful fixing in place.

[Neil Gaskin]

As a contractor, I’d replace it.

Fixing is is an option but not practical from a time/cost perspective if you value your time.

[Ryan Yeaglin]

As a contractor, I’d replace it.

Fixing is an option but not practical from a time/cost perspective if you value your time. As a contractor two things: your getting paid, your labor is cheaper to just replace the door. As a homeowner, maybe the OP has a spare few hours or now with the Covid19 crap is laid off and trying to save some $$$. Either way a repair isn't all that difficult if the rot is contained in a few inches. Use polyurethane glue and an epoxy sealer over the repair and you'll be in good shape.

[Dave Sabo]

As long as the wood behind the hing is solid , you can fill in the shredded part. Either with a wooden plug , or with epoxy filler or bondo.

If the hinge wood is soft - NEW DOOR - end of story.

But................................before doing any work you should determine where the water that rotted that section is coming from. Then you need to rectify that; or any repair you make is no more than a band-aid.

[Jim Andrew]

2nd on the bondo. I find that bondo is a great wood filler, sticks to the wood, will not fall out, does not rot. If you can just remove all rotted wood, fill it with bondo, let it dry, sand and paint it. Done.

[julian abram]

Yep, decided to go the repair route, got more time than money. Took the door down today and moved into the shop. Will do some kind of plug and fill method after I get all the rot out. Good info, thanks for sharing.

[Bob Deroeck]

Hi Julian,

I suggest taking the approach recommended by Mel and Dave, but with a caution about Bondo. First find out the source of the water. I suggest taking off the door and removing the lower hinge to see how far up the rot extends. If it starts at the hinge and the wood is solid above the hinge, then water likely entered from the hinge screw holes. But try to determine exactly where the rot starts. Assuming the wood is sound above the hinge, I suggest you take one of two approaches, depending on how deep the rot extends. If the rot extends through most of the wood, both front to back and from what was originally the outer face to the styrofoam , then I suggest you remove all of the wood below the point where the rot starts. At the bottom of the sound wood, cut a scarf of about 4" length (top to bottom ). Then cut a new piece of wood to fit in the cavity with a matching scarf to mate with the remaining wood. Roughen the front and back fiberglass skin where the replacement wood will be inserted with sandpaper, then tack off the dust. Use a good quality epoxy, such as West System, to epoxy the replacement piece to the front and back fiberglass skins and for the scarf joint. I recommend not using five-minute epoxy from the hardware store or a big-box store since it has relatively little strength compared to quality epoxy. If the replacement wood is not a tight fit to the fiberglass skins, then use a mixture of epoxy resin and colloidal silica to make a paste that will fill any gaps and will not run out of the joint before the epoxy sets. I suggest not using pressure-treated wood since the epoxy will not bond as well to PT wood as untreated wood. Cut the rabbet for the hinge, then prime and paint. Caulk each hinge screw hole before installing the hinge.

The second approach is if the rot does not extend all the way from front to back and from the outer face to the styrofoam. In this case cut out the rot, then cut a piece of wood to replace the rotted stuff. The fit doesn't need to be perfect. Glue in the filler piece using a non-sagging stiff paste made of high quality epoxy resin with colloidal silica filler. Coat all surfaces with this paste than install the filler piece and screw it into place so the epoxy can set. The excess epoxy mix will squeeze out, filling all the gaps. Leave the squeezed out mix in place. After the epoxy sets, remove the screws and remove the excess filler with a rasp or file. If there are still some gaps, you can use Bondo to fill them, but since you have the epoxy and silica, I would just use that material. Bondo has very little strength. I suggest you not consider filling a large area with Bondo, especially around the hinge area where strength is required.

This repair should take only a few hours of actual work time, not counting time required for the epoxy to cure. While replacing the door with a new slab sound much easier, you may need to make adjustments for the lockset and hinges, which could take some time. With a repaired door, you know if will fit the frame as well as it ever did.

Good luck.