Repairing Outdoor Wood Railings

Our house has been undergoing many exterior repairs over the last dozen years, including new doors, rotted sill replacement, window-frame rot fixes, replacement decking, siding replacement, new stairways, new paint and plenty more. Some of these repairs were necessitated because the builders did not stick with good-sense carpentry (door sills level with uncovered decking), some are from manufacturer defects (windows), and others are simply due to the climactic extremes we have in Minnesota (-35F to 100F, 20% RH to 99% RH).

New front staircase: more steps, lower rise, reused wood, and retail railings.

I began working on this porch in 2013, when I replaced the main staircase that was made from stock stringers with too few steps for the total rise. Over the following years, I could see that the porch railing was failing where exposed to the elements and needed reconditioning where partially exposed. Professional porch repair can get expensive fast, and results can vary. You may find the contractor using treated wood where you wanted cedar, or the style of railing may no longer be commonly available. Add to this cost the next job, porch painting, and costs may become downright prohibitive. This is where you step in to figure out how to repair it yourself. Fortunately, with a few simple products, you can fix rotten spindles, bottom rails, and expensive top rails, without too much skill or effort.

Before plastics and treated wood became common porch construction materials, many mid to late 20th century porches were made with Western Red Cedar —a naturally warp and rot resistant (not rot proof) wood grown in North America. This is what our porch rail posts, spindles and bottom rails were constructed with. I believe the handrails were made from Douglas Fir. 

 

Porch railings are often constructed by quick-moving builders who do not have time to make the little adjustments that will allow rain, snow melt, and dew to drain from bottom rails. Water standing for any period of time on paint and wood will eventually lead to decomposition of both materials. The railing repaired in this post is about twenty-five years old, a little older than the amount of time I would expect above ground, partially-roofed cedar to last in our moist environment. However, the fully exposed railings on stairs and uncovered decks were partially or fully-rotted by the 20-year mark.

 

The porch railings to be repaired —from this distance, all looks well!

 

Below I will go over techniques for repairing the upper accent rail seen in the above picture. These same techniques can be used to address the spindles, lower rails, and possibly the handrail. If you have a porch built before 1940s, porch woodwork can be more ornate than what we see on houses built from the 1980s onward, which tend to have simple square spindles and few decorative embellishments. Older homes can be repaired using similar techniques to those I describe below, so read on if you intend to work on an older home's porch.

The Problem

 

Decay is usually found near the bottom. Here, where the spindle meets the lower rail.

 

Wood placed against wood will hold moisture and eventually decay, even when painted. In fact, the rotting wood will undermine the surface coating leading to paint failure which you will notice first. Rotted wood is soft, sometimes crumbly, sometimes green with algae, and sometimes even releases moisture when pressed. This is most likely where spindles meet the bottom rail, particularly at porch corners, where they receive rain from two sides. The spindle's end grain wicks up moisture into the wood.

 

Another common location for rot: where the bottom rail meets a post.

 

Another prime spot for decay is the bottom rail ends, particularly at the porch corners. Water running down the porch corner posts and spindles collects at the bottom rail. The rail's end grain wicks moisture into it and the spindle also wicks moisture up into itself, holding moisture against the bottom rail. Nails or screws driven from the underside of the bottom rail, up into the spindle, helps to bring moisture into the spindle and lower rail.

Accent rails and spindles at the top of the porch

 

Top accents at the front of a porch don't see much rain thanks to the overhang, but porch side accents see sun and rain on the south side and, on the north side, may never dry out for lack of sun. Both conditions lead to rot. Although it's commonly understood that a shady, damp north side of a house can rot, it's surprising to hear that a full day of sun can also lead to decay. This is caused by greater exposure to UV rays, more expansion and contraction, as well as moisture. 

Accent rails that have been repaired, primed, and are awaiting new spindles

 

The Tutorial

 

This tutorial will show you how to fix porch railing rot using the accent rails as an example. The process for fixing the lower railing is exactly the same as the upper accent pieces —only with longer spindles. If the handrails have rotted, this is another matter entirely. It is often difficult to source matching handrails for older porches. You can have new lengths milled, at a cost. Alternatively, you may choose to replace all the handrails, at once, with a new profile. Another option is to try to repair the handrail, piecemeal —I've certainly done this, to greater and lesser success. I will need discuss that in another post. 

First Steps

The first step is to take your accent rails down. On homes built before 2010, these rails are typically installed using phillips head screws driven up into the porch roof framing. First and last spindles are sometimes attached with finish nails or phillips screws into porch posts. These should all be fairly easy to remove. If nails are used, or screws spin but do not come out, you can use a small pry bar -but this can do some damage. Its better to use a tool like the one shown below to cut nails or embedded screws that spin, but don't come out.

My Fein Multimaster 350Q is now out of production.

 

The Feintool Multimaster oscillating tool is my home repair go to power tool. If you do any kind of work where tight space, flush and low-impact cutting/sanding/more is demanded —you didn't know you needed it until you have it at your disposal. There are lower cost brands, of course, but my Feintool 350Q hasn't let me down yet. I believe the Feintool 500MM is the successor model to the 350Q.

 

You can use the Fein metal-cutting blade (see pic, below) to slice through hidden nails and common screws. However, be aware that hard screws will wear your blades faster than nails will. Blades are the expensive part of a Feintool Multimaster. There are cheaper options, in blades and oscillating tools, but you pay with usability and longevity when you take the lower cost route —ask me how I know! 

 

Where precision counts, go with the name brand blades (Fein, but I've also used these Bosch blades) or where there is scrappy, semi-demolition wood work to be done, I've used these much lower cost Actomaster blades. No matter what you choose, buy blades in bulk to save a few dollars, protect them in your kit, and use them wisely to save on wear and tear.

Bimetal #157 Blade. You can use it on wood, but it is designed for metal cutting.

 

Separate The Rail Elements

The lower portion of a porch railing is where much of the decay can be found.

 

Once the railings are down, it's time to take them apart. Parts that are really rotten will be easy to separate. Detach spindles from the bottom rail -typically attached with 16-18 gauge brad nails applied with a pneumatic nail gun. These nails are soft and flexible, and sometimes the spindles can be pulled apart from the rail. If they don't separate easily, you can use the Fein Tool to slice through these brads. The goal, for me, is to protect the milled pieces, so I am okay with leaning into the spindles with the cutter to spare the bottom rail. It is uncommon to find screws connecting the lower rail to the spindles because the heads would be visible.

The top board is typically a 2x4 and is usually connected to the spindles with phillips head screws. These should be easily removed with a cordless drill and #2 phillips bit. I would not expect the top board to need to be replaced as it is fairly well protected. Again, if screws do not come out, consider cutting them between the spindle and 2x4 piece with the bimetal blade. Anything in good shape can be saved and even improved. I'll show you, below.

Feintool Multimaster with sanding attachment can be used to sand railing components.

 

I go to my Feintool Multimaster and sanding pad attachment to quickly remove loose paint on any railing pieces I plan to re-use. The sanding pads, in all grits, come in boxes of 50. I use 60, 80, or 120 grit to remove paint on these pieces. These hook and loop pads are relatively long lived, but their most valuable feature is the ability to rotate the triangular pad to help with difficult corners. Before you jump into sanding square spindles (it is tedious), consider simply replacing them with new wood.

Basic spindles are cut lengths of 2x2 cedar, usually dry, smooth, and straight.

 

I want to replace all of the spindles, rotten or not. Why? Because the spindle is the lowest cost piece of the railing and too much effort to clean up the old ones. You can buy 8 foot lengths of 2x2 cedar at your local box store or lumber yard, but it may be even better to buy the 36 to 42 inch, pre-cut western red cedar spindles because these are straighter than the 8 footers. Another reason to buy new spindles is that this repair is really a modification requiring 1/4 inch more length than the original spindle so that they can be beveled ever so slightly. Lastly, the spindles are often beat up when they come off the porch and to mix new with old can look unkempt. For absolute cost savings, use the old spindles and expect to cut them shorter. Just make sure the nails and screws are removed before cutting!

A word about choice of wood: you may be tempted to buy treated lumber for any or all aspects of your repair project. I reject treated wood, typically pine, for porch railings. Why? It simply is not stable enough. Where I've used it, it has often twisted, pulled screws or nails, split, and formed mold on the surface where not painted. Painting it is also a problem, often requiring an adequate drying time before a coating can be applied. In that time, the drying process can twist or warp the wood. It's simply not good for this forward facing part of your home!

The simple, useful miter saw. Nothing fancy needed for this job.

 

You will need a miter saw for this repair. For spindle cutting, it does not need to be the costliest machine available. What I am using here is a 10" Dewalt DW703 I bought in 2004! Can't get that model anymore, so I recommend its successor, the 10" Dewalt DW713. If you don't have the resources for a powered saw, but have a mitering hand saw (good old barn tool find), it'll be much slower, but can be done! After all, western red cedar is fairly soft and easy to cut. Whether by hand or power, your blade should be reasonably sharp. The common 40t saw blade from Dewalt will work just fine.

First, cut your spindles 1/4 inch longer than needed. For example, if 6.25 inches is required length for the finished spindle, then cut each to 6.5inches. This leaves room for the coming bevel cuts. This bevel is important because it will spare you from rot returning as quickly as it had the first time by allowing water to shed.

 

Measuring accurately is important. -the blade tooth lands squarely on the 6.5 inch line.

 

Pro Tip: To ensure that all spindles are cut to exactly the same length (important!), clamp what is called a stop to the back fence of the miter saw. This can be done on a power or hand miter saw. I've used a piece of 3/4 inch thick plywood that I checked for square (see picture above) and ensured that it is mounted flat to the miter saw fence and table. Use a "C" clamp (pictured below) to ensure no movement of the stop.

Make sure that your stop is square and tightly clamped to the fence!

Pro Tip: Before making your cuts, be safe. Wear safety glasses and a dust mask, or what I prefer -a full face shield with lung protection. It offers better dust protection and full face projectile protection. Below is my 3M 6800 respirator. The 3M 6900 is readily available and great for a variety of pollutants. The particulate filters that come with the 6900 are good for this project and others. The silicone seal is remarkably comfortable given its level of protection and it is replaceable should it snap. Honestly, I wish I bought one of these 20 years ago. Protect yourself!

 

A combination dust mask and face shield  —the 3M 6800.

When your stop is in place, and are sure of the measurements, cut all the spindles needed for the project. After all the needed spindles are cut, it is time to make the final miter cuts.

After the bevel-cut: note the subtle angle between the spindle and square

 

Again, to ensure that all cuts are exactly the same length, we measure and clamp a stop to the back fence of the miter saw. Remember that these will be miter cuts, just a little bit off 90 degrees, so that the bottom rail points downward ever so slightly when installed. The measurement between the stop and the blade, set square at 90 degrees, is 6.25 inches.

Once that 6.25 inch is set, it is time to move the blade's miter position about 4 degrees away from the stop (moves blade to the left in this example) and lock it in place by tightening the front knob. Placing a 6.5 inch spindle between the stop and the blade, I hold it firmly with my right hand much closer to the stop than the blade. Triggering on the blade, I allow the motor to get up to speed, then cut through the cedar spindle slowly. I not do a quick chop down and jerk up! Hold the blade in the down position until it slows to a stop. This will protect the wood from tear outs and splinters while protecting you. Upon raising the saw blade, a slight angle will be visible on the cut spindle. 

Using a square it is easier to see the subtlety of a 1:12 bevel cut

This angle gives the spindle a length of 6.25 inches on one side and about 6.375 inches on the other. This little bit changes everything. A one eighth inch drop, across the spindle's 1.5 inch width, is the same slope as the 1:12 slope required to effectively shed water. It is the reason the bottom rail will now drain water instead of hold on to it. 

 

After all the spindles are bevel cut, ensure the bevel slopes outward when attaching to the bottom rail. Trust me —an 1/8th inch bevel can look like a square cut after a long day! So make sure that each has the longer side of the cut pointing outward on the bottom rail before attaching. See the image, below, to get a sense for the look. When mounted on the porch, the spindles will be plumb, but the bottom rail will tilt slightly downward, away from the porch.

 

On the bottom rail, it is hard to see the bevel cut, but it is visible in angle of the spindle

 

Pro Tip: There are times when it is easier to prime, and possibly paint, all the spindles before affixing them permanently with brads or finish screws. Priming and painting can be done after assembly, it is just a little fussier to do once assembled. This is entirely up to the you.

 

So is that it? It could be, or take rot resistance to the next level by reading Part II: Using Epoxy For Porch Railing Repair... where I will discuss using epoxy to restore components of the porch rail system, tips for attaching spindles and rails, filling holes, and the excesses to which I go to add longevity.

*Please note that the tools and products in this post are the one's I actually use, and if I link to a different product, it is only because it is a successor model to mine. 

 

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