As with any structure exposed to the elements, decks and fences should be inspected for rot, rust and rickety supports. Far too many homeowners never take this simple step. As a result, the International Association of Certified Home Inspectors estimates that of the 45 million existing decks in North America, only 40% are completely safe.
Walk your fences and decks once a year or so to look for signs of decay or structural failure, and schedule maintenance accordingly. You can perform this inspection at any time, but I’ve found the best time of year is normally spring.
Spring is when any snows have melted off, but before new plant growth has risen up, giving an excellent view of fence and deck supports that might otherwise be obscured. Spring is also a good time to check decks for structural issues, as most decks fail during the summer, when crowds gather on them to enjoy the weather.
A deck that’s twelve inches off the ground has very different support and safety concerns than one that’s twelve feet overhead, but the basic issues to watch for are the same. You’re primarily looking for signs of rot, and any structural shortcomings.
Using a screwdriver or awl, probe the decking material. Wood decks should feel solid when tapped, and splinter when gouged. Rotten wood will easily give way to a probing, and fibers will pull loose without splintering. Keep an eye for holes or small piles of sawdust, which may indicate insect activity. Composite deck materials are resistant to rot or insect activity, but should still be looked over for signs of damage, such as warping or bowing. Damaged structural materials will need to be patched or replaced, depending on how widespread the damage is.
If you do find signs of rot, don’t stop your inspection there. Decks are designed to be able to withstand weather, and they can take getting wet. However, they are not able to be consistently wet over a long time. Look for water sources that don’t allow deck materials to dry out, such as sprinklers, improper grading, or downspouts that keep the decks wet.
On decks, proper flashing is essential to shed water off of wood surfaces and to prevent rot. If the wood surface being protected is pressure-treated, check to see if the flashing is aluminum. Aluminum corrodes when placed in contact with pressure treated wood, so flashing will degrade over time.
The methodology behind deck structures varies according to the deck material, type of connection to the home, size of the deck, and local ordinances. There are enough variables in that equation that we can’t cover the entire topic in this article, but even a casual inspection can be helpful to identify trouble spots before they become major issues.
As you look over your deck, give the structure a shake. Support posts should look and feel solid. If you sense a ‘wobble’ when you shake them, or if it looks as if a footing is coming out of contact with the ground, then bring in a pro ASAP.
Look for any materials in the deck structure that aren’t designed for exterior use. For example, all fasteners on your deck should be corrosion-resistant. (If you see rust stains around fasteners, take this as a warning sign.) In addition, any wooden posts in contact with soil should be pressure-treated AND rated for ground contact.
Deck hand rails should be about 3’ high, and pass the 4” ball test—a 4” toy ball should not be able to fit between the railings. (In this test, the 4” ball is a stand-in for a toddler’s head.) Your local code requirements may have different requirements for these measurements; if so, follow their guidelines to be sure you’re in compliance.
To check the condition of the deck’s surface, spray it with water. Whether it’s painted, stained, or composite, the water should bead on the surface, rather than soaking into the material.
Lastly, a note about hot tubs. Hot tubs are a popular feature, but unfortunately, many hot tubs are added after the deck construction, and the decks they sit on are not designed to hold their weight. A gallon of water weighs just over eight pounds, so a hot tub holding a couple hundred gallons of water, plus half-dozen people, can easily top the scales at over a ton. That’s like parking a compact car on deck. If you have any doubts about whether your deck can hold that kind of weight, bring in a pro to do a thorough analysis.
Fence inspections are a little easier to conduct than deck inspections. Walk the fence line with a screwdriver or awl (I like to use a multi-tool for this), as well as a hammer and a spray bottle.
Look over the fasteners to make sure they are securely seated. If you see any popped nails, now is a good time to give them a tap back into place. If the nail is still loose, try a different angle, longer nail, or different fastener location.
As you walk the fence, reach out and give it a gentle shake from time to time. If any sections feel weak, try to find out if it’s a fastener issue, or something else. Give the boards a poke with the screwdriver or awl, checking to make sure the material is firm.
Examine the fence posts during your walk, as well. Inspect the base of the posts for signs of rot or decay. The most important aspect of fence posts is that they are seated far enough in-ground to be below the frost line for your climate. Look for any posts that are starting to heave up out of the ground. If you see this happening, chances are that those posts will need to be replaced and installed properly.
If you see any excessive moss or mildew growth, look for the cause. You may find a simple solution, or it may be something you can’t modify—such as a shady run along your neighbor’s home. Clean off the growth, and consider touching up any stain or paint as needed.
Speaking of stain, the best way to check whether the stain on your wood fence needs a touch-up is to spritz it with water from the spray bottle. The spray should sit on the surface in beads. If it soaks into the wood, it’s time to refresh the stain.
I’ve mostly been talking about wood fences so far, but the same techniques apply to metal or composite fencing. Any metal fencing material is designed to withstand the elements, but damage like scrapes or dings can leave them vulnerable. Rust in its early stages can be cleaned off and the fencing can be re-treated with a protective coating. If the fence has lost its structural strength, it’s time to replace the affected section.
A special note: Pool Fences are a separate creature, with concerns beyond simple physical condition. Local requirements vary widely, so you’ll have to check with your local regulatory agency in order to be sure that your pool fence meets all requirements. Common problem areas include height, railing gaps, gate swing, and latching mechanism.
Hopefully, your decks and fences pass your inspection with flying colors. Take care of any maintenance as needed, and you can look forward to another year of enjoying your yard!