Thursday, 9 May 2013

DIY: How to fix wood rot in 6 easy steps

Wood, especially if it's untreated, can easily start to rot once it comes in contact with moisture – and we have generally plenty of water coming down from the sky here in Auckland. Wood rot usually starts when water gets into cracks or when water penetrates a wood finish and can’t dry out.
My customers often think that rotted wood in and around the house is beyond repair, but this is usually not the case. You will have to consult an expert like Banks Building for structural rot, but small areas you could tackle yourself if you’re game. Get yourself a bit of epoxy , woodhardener and know-how, and fix those rotted areas of wood on decks, architraves, doorway and window frames in your house. 

Let me provide you with a bit of know-how, so you can give it a go. 

First of all you’ll need some advice on how to diagnose wood rot. Test the wood by tapping it with a blunt knife. If it feels very soft or crumbles, it's rotted. Now, as long as the area of rot is less than fifty percent of the total area of the wood, follow these steps to fix the problem:

1.       Before you start please:
a.       Read all warning labels
b.      Make sure you wear protective gear:  goggles, gloves, a dust mask and any other recommended protective equipment.

2.       Use a screwdriver (flat head is best) and chisel to remove all rotted wood. This part is relatively easy, as the rotted wood will crumble into pieces. Don’t worry too much about carving and digging out every last bit of rot. The liquid epoxy will soak into areas that can be saved.

3.       Drill small holes (a honeycomb pattern works best) at an angle to help the epoxy penetrate throughout the decayed area.

4.       Apply a liberal amount of wood hardener onto the area using a disposable brush or spray bottle. Let the hardener saturate and allow to cure/dry.

5.       Mix the two-part epoxy on a piece of scrap wood and apply into the areas you’ve cleaned the rot out.
Tip: Epoxy dries very fast and is very hard to remove- great points, except when it comes to you and your tools! Apply and fill quickly and clean up as you go along.

6.       Let dry and sand the area to match the shape of the original wood. You can also use a rasp, when you need to remove quite a bit of the dried filler to match the original shape. Rasps come in a wide variety of shapes for flat and contoured surfaces.

You can cut, shape, smooth and drill into cured epoxy just as you can with wood.

If you feel a bit daunted by the above, or if you have to deal with rot in structural parts of your house, please give Banks Building Maintenance a call to get a free quote on fixing any wood rot issues.

Last but not least, you'll also want to preserve your wood to prevent future damage. We at Banks Building Maintenance are happy to give you a hand with that, but there might be some things you could do yourself as well. Here are a few tips: 

  • Use treated timber for decks and other outdoor structures. Never allow untreated lumber posts or lumber to rest directly on concrete.
  •  Waterproof and seal any natural wood that might be exposed to moisture. 
  •  Regularly inspect your house for peeling paint or other paint failures, especially near joints. This is where water might start to seep in. Have a close look at window frames and window sills, wooden architraves and door frames. Repair rot as soon as it starts appearing to help prevent further damage. 
  •  Seal large cracks and gaps with a product like Selleys No More Gaps. If you are working on the outside of your house, make sure you use products which state that they are suitable for outdoor use. You might also want to check if they are paintable (for example, silicone is not paintable), otherwise the end result might look a bit shabby. If possible, use screws to close any open miter/corner joints. 
  •  Sand any bare wood and apply wood preservative before you apply a primer. Seal joints with No More Gaps after priming and before the top coating.

Cheers, Andre


  1. Nice posting about How to fix wood rot in 6 easy steps.......

    building maintenance brisbane

  2. Your postings is very nice and have helped me a lot for repairing the rot in the wood. I have had an experience repairing Roof leaks with EPDM's RV Roof leaks Repair
    product named Liquid Roof. You should write a post on it.

  3. Thanks for the bathroom home improvement tips! Another helpful DIY site I enoy is the House Logic website.

  4. When on the job, we always were working. There was no time or place for slackers. In fact, if dad caught you slacking.