Rotted Wood

How do you fix rotted wood without replacing it?

If your home has wood trim, chances are, there is some degree of wood rot in it. The rot will either be very noticeable, concealed in hard-to-see places, or concealed under a thin layer of paint. If you have rotted wood, be aware that it has to be repaired or replaced to prevent water, air or bug infiltration into your home.

Wood anywhere in your home is vulnerable to decay in the form of wet or dry rot. A rotten wooden door, floorboard, section of the trim, window sill, or column, maybe just the beginning of potentially serious problems. As a fungal infestation, rot can and will spread rapidly unless you take care of the trouble right away. Although replacing damaged wood is often a major hassle — not to mention the strain it puts on your wallet — cheer up! A complete replacement is often unnecessary for non-structural-support woodwork. Instead, build up the weakened area with the help of several easy-to-use products. Here’s how.

Wood rots due to the presence of enough moisture for fungi to use the wood as food. The fungi damaged areas extend well beyond the visible rotten wood. Any rotted wood repair that is to last has to treat the wood that has started to rot but is not damaged, in addition to the wood that has started to rot.

At Hitch Property Constructions, we offer timber repairs work from simple timber repair to almost new structures, renovations, and extensions.

What does rot in wood look like?

The image below shows two adjacent 20mm thick sections cut from a rotten glulam beam(a beam made of sections of timber glued together). These are commonly used as structural timbers and are available in very long lengths.

Rotted Wood

What products are out there?

When filling holes in wood, there are two basic types of commonly used products (although there are several different brands of each): wood filler-type products and wood restoration products or kits.

Wood Fillers

Wood fillers are products such as Bondo and Minwax that are designed to be all-purpose fillers for gaps, holes, and rotted wood. Their application is simple, they cure quickly, and they’re not supposed to shrink once dry. However, they will shrink slightly and sometimes begin to pull away from the edges of the wood, especially in exterior applications where they are exposed to the changing weather. These kind of products are common for a variety of uses, but may not always produce perfect or long-lasting results. They do have their place, though–they can be used for quick short-term fixes and are great for small tasks like filling nail holes and such.

Wood Restoration

The bigger the projector, the more serious you are about getting a professional-looking finished product, the more likely it is that a wood restoration product or kit is the better option. One of the most well-known options (and the one that we here at CSHardware recommend) is Abatron’s wood restoration kit. These work for just about any project that requires filling in wood (although filling nail holes with the stuff would be overkill). You can use it on projects as small as filling in missing chunks of damaged floorboards, or as large as repairing rotted portions of wooden columns or logs! One of the most common applications of wood restoration products like these is repairing window sashes with severe rot damage.

How to Check for Rotted Wood

Consider walking around your house a few times a year and inspecting the wood for rot.

  • Look at the edges of the trim, especially where it meets the roofline or meets the ground.
  • Look at window sills and other wood components that lay flat and allow water to settle on them.
  • If you are unsure if an area is rotted, then gently push on the area with a small screwdriver; if it sinks in and the wood is soft, it’s rotted.

Ok, so you’ve got rot! Let’s talk about why it happened, what can be done to prevent it and options for repairs.

What Causes Wood Rot?

First, wood rot occurs for a couple of reasons but mainly due to the quality of the wood used and the installation method.

Wood Quality

Most tract homes over the past twenty-five years used “finger-jointed” pine wood as the trim. This type of trim is the poorest of quality and typically fails on a home within just a few years. The finger-jointed wood is a piece of trim that has been fabricated/assembled with short pieces (or scraps) of wood that are then glued together at finger joints. The wood is then machined and primed and looks great the first day it’s installed.

However, once the wood gets wet (mostly the end grain) or the paint coating fails just a bit, the finger joints, which are all end grain, quickly soak up the moisture, and the wood rots. Also, the pinewood that is typically used comes from pine trees that are force-grown, which results in a softer product that is less dense than normal wood. If you were to compare old-growth pine wood to today’s fast-grown species, you might find a more dense wood that holds up well.

Improper Installation

Another reason wood rot is improper installation methods, mainly not priming or painting the backside and ends of the wood. I can’t tell you how many homes I investigate and price a paint job for that have all of the ends of the trim wood exposed to the elements and unpainted. It’s these ends that soak up water from the house and air and start the rotting process.

Additionally, if the trim wood is installed so that it rests on a roof and the end grain is not sealed, guess what? All that roof water will soak right into the trim wood, and it will rot.

The same goes for wood resting on the ground or wood resting directly against masonry or stone. Masonry of any type is very porous, like a sponge: it soaks up water and then transfers that water to the wood, and while the masonry holds up, the wood fails.

How to Fix Rotten Wood on a Roof

Whether you are replacing your entire roof or repairing a small area, fixing rotten sections of roof decking, or sheathing, is vital to creating a sound, watertight structure. Roof decking, which is nailed to the roof’s trusses, holds roofing materials, including felt paper and shingles and also serves to stiffen your home’s structure and protect it from the wind. Replacing the rotten roof boards helps protect the integrity of your home and prevents damage from leaks.

Check out our range of timber repairs Melbourne at Hitch Property Constructions. 

Locate Dry Rot Roof Damage

If you’re only replacing the portion of the roof with damage, you need to find out the extent and location of that damage. Inspect the inside of your home for leaks. On a rainy day, look for stained drywall or wood on ceilings and in attics or crawl spaces. Remove drywall and insulation as necessary to locate water stains on the underside of the roof decking. During a reroof, inspect the decking after the shingles and underlayment have been removed. Tap water-stained sections with a hammer to test their stability.

Remove the Shingles

Pry up shingles around the damaged area. Eight nails typically secure each shingle: four through the middle just above the tabs and four through the shingle above it. Pull up the felt paper underneath the shingles. Working your way up the roof, expose all of the rotted wood. Leave the next course of shingles intact by carefully removing the second set of four nails. During a reroof, start at the peak of the roof and remove all shingles, prying them up with a pitchfork, working your way down the roof.

Remove the Rotten Wood

When replacing roof decking, you first need to get rid of the old, rotten section. You may need to cut a little extra to expose enough of the trusses and make sure you get rid of all the rotten wood. Set the depth of your circular saw to the thickness of the roof decking. Cutaway the damaged area. Pry out nails with a claw hammer or pry bar and remove the cut piece. Expose at least two trusses so that you can nail the replacement wood to them to make the replacement section stable. If possible, keep the cut-out section in one piece so you can easily measure and cut the replacement piece.

Replace the Roof Decking

Select plywood or oriented strand board that is the same thickness as the wood you are replacing. If you were able to keep the removed section in one piece, measure it. If not, climb the roof and measure the opening so you can cut the replacement piece to be a perfect fit. Orient a piece of the replacement material so that its grain runs perpendicular to the roof trusses, and cut it to the dimension of the opening. Place the cut piece into the opening and secure it to the trusses with nails placed every 4 to 6 inches.

Replace Underlayment and Shingles

Once you repair the hole in the roof plywood, you need to seal up the seams and recover the roof. Cover the seams between the old and new decking with bitumen tape. Lay felt paper onto the roof, overlapping the existing paper to get good coverage. Staple it to the roof decking or nail it with plastic-capped roofing nails.

Now you’re ready to replace the shingles that you removed. Slide new shingles under the top undisturbed course. Lift the shingle above it and nail it first through its centre, then through the centre of the shingle above. Continue laying shingles in the established pattern until the entire repair is covered.

When you fix rotted wood on your roof, you help to keep it watertight to prevent leaks and additional damage. Whether you replace the entire roof or just a section, the work you do gives you more life out of your roof.

Wood Rot Prevention

Proper Installation

Wood should be:

  • Decoupled from the masonry with flashing or with an air gap and never rest on the masonry or the ground.
  • Primed and painted on all six sides prior to installation.

That’s right, even the backside of the wood should be painted. If it’s not, the water and moisture from home will make its way into the wood from the backside as well as the front side. You may have heard of this term called “back-priming,” which is when the component is primed on the backside before installation.

Preventative Maintenance

Finally, general preventative maintenance is another way to protect against wood rot. Wood trim in New Jersey should be cleaned, caulked and repainted every three to seven years depending on its condition. If the wood is not painted regularly, the paint will fail, and the wood will not have any barrier to the elements and will soak up water. If it’s not regularly painted, then you can “pay me now or pay me a lot more later.”

Repairing Rotted Wood

Ok, so you back-primed the wood trim, you painted it on all six sides, you kept it away from masonry and rooftop surfaces, and you kept it painted every five years. It should last. Unfortunately, even the best maintenance plan sometimes results in rotted wood in New Jersey’s tough, wet environment. Let’s talk about options for fast repairs, general repairs and permanent solutions for rotted wood.

The Quick Fix

A cheaper, faster repair method is to dig out the rotted section, let it dry, then fill the area with epoxy, prime it and paint it. This type of repair works well when you’re trying to save money or if the rotted area is difficult to replace (and when the rotted area is dry enough to accept the filler). Another way to make the repair is to use wood filler. However, be aware that even exterior grade wood filler is porous and typically fails within twelve months, so use epoxy.

General repairs can be made by using pine wood. The worst choice would be finger-jointed, followed by a better choice of clear pine. Clear pine means the wood has no knots. You could remove a section of the rotten wood, prime a new piece all over, paint it one coat, then install it and finish coat it. (Of course, it’s likely to rot again eventually.)

Permanent Wood Rot Solution

A permanent repair can be made by removing the entire piece of wood trim and replacing it with a man-made piece of trim. Most man-made trim is PVC, such as the Azek brand, and it can be shaped and installed the same way as wood. PVC doesn’t have to be painted but looks much nicer caulked and filled and painted white or another trim colour.

Boral For Trim

Another permanent trim material is Boral brand. This material comes in brown colour and will accept darker-coloured paints such as Tudor Brown. Boral is a partly-recycled poly-ash material, is installed easily, and paints up well. Typically, premium lifetime paint, such as Sherwin Williams Duration, is the best choice for top coating these alternative trim products.

Cedar Wood

If you are looking for a purist solution (no plastic on the house), then consider replacing failed areas of wood with cedar trim wood. Cedar is rot resistant and if properly installed and maintained, will provide many years of service.

Wouldn’t it be nice if, in the United States, the standard was to build homes to last hundreds of years, rather than just twenty, thirty or forty before having to start stripping off cheap finger-jointed trim and/or cheap siding? I’m baffled as to why our building codes even allow such inferior products.

What You Should Know About PVC 

Also, while PVC appears to be a permanent solution, it has only been out for a short time, and that material too may not be permanent. It could break down from UV rays and ozone. PVC can warp and twist and move with drastic temperature changes if installed too tightly or with improper fasteners. Make sure if you go the route of using premium materials you invest in a qualified contractor so that you get sound advice and installation.

How to Repair Rotten Wood Without Removal

If the damage is caught early enough, removing the rotten wood and using an epoxy filler strengthens the damaged area. Once the wood is repaired, take the necessary precautions to ensure more moisture cannot cause further damage.

  1. Place a wood chisel near one end of the damaged area. Use a hammer to tap the chisel’s back end and push it through the rotten wood, removing it. Continue hammering the chisel through until as much of the rotten wood as possible has been removed.
  2. Rub a wire brush over the damaged area to remove any loose wood pieces. Drill shallow holes into the damaged area using a one-quarter-inch drill bit. Space the holes approximately 1 inch apart.
  3. Mix a liquid wood epoxy according to the manufacturer’s directions. Pour the liquid into a squeeze bottle. Apply the liquid to the damaged area and squeeze it into the holes you drilled in Step 2. Use a small paintbrush to spread the mixture over the damaged area’s entire surface. Continue to apply the liquid wood epoxy until the area is fully saturated.
  4. Mix a wood epoxy according to the manufacturer’s directions. Scoop a small amount of the mixture up with a putty knife. Use the putty knife to apply the mixture to the damaged area. Press the mixture firmly in place, so it gets into all the gaps and adheres to the surface.
  5. Use either the putty knife, a small strip of wood or your gloved fingers to smooth and shape the wood epoxy to closely match the damaged area’s surrounding surface. It does not have to be perfect at this point. Allow the epoxy to dry for approximately 4 hours.
  6. File down any ridges in the epoxy with a rasp or piece of 80-grit sandpaper. Try to get it to match the surrounding area as closely as possible. If you sand away too much epoxy, mix a little more following the manufacturer’s directions and apply it.
  7. Smooth out the repaired surface with 120-grit sandpaper. Use a paintbrush to apply a coat of alkyd primer to the epoxy and surrounding area. Allow the primer to dry before painting fully.

We have a wide range of Melbourne timber repairs for your home renovations. Check out Hitch Property Constructions.

Professional Rotted Wood Repair

There is a lot to consider when maintaining and repairing the exterior of your home. All Trades has the expertise and solutions for your rotted wood repair and painting requirements. Call me or send over any questions! We’re here to help and would be very interested in your opinion. I’d be happy to meet with you to look at the condition of your home and to recommend a proven maintenance plan for your trim and house paint.

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