Building decks is fun. I can’t lie. I love doing it, and so does my team. I’m going to suggest you always hire a professional if you want to maximize your outdoor space and build the deck of your dreams. This post is going to highlight why. A lot of things can go wrong when doing it yourself. Even though it’s a rewarding project, it’s not easy.
Small mistakes can lead to big problems. Whether you’re planning to build a traditional wood deck or looking into composite decking, I wanted to review the decking mistakes we see most often.
Mistake #1: Skipping the Permit Process
I’m not saying this is you, but a lot of homeowners just get to building their decks without thinking about local ordinances and permits. They may seem like red tape, but these are in place to keep you safe and things looking nice.
Local building codes require permits to verify that decks satisfy safety standards, structural requirements, and weight-bearing specifications. If you don’t follow the right procedures, you could be fined. (Even worse, you could build an unsafe deck.)
Every local government sets particular requirements for things like footing depth, joist spacing, railing height, and attachment techniques.
Sound Like A Lot? Get Professional Help Today.
Mistake #2: Inadequate Footings and Foundation Issues
Footings have to be done right. No exceptions. I’ve seen decks where everything looked good on the surface. Before long, though, the structure started leaning and sagging.
This mistake is dangerous and costly.
Where we live, the footings need to be deeper than in other areas of the country because of our freeze-thaw cycles. A footing needs a concrete pier that expands at the base for stability and reaches above ground level to protect wooden posts from moisture. Placing posts directly on the ground or using concrete pads or cinder blocks creates an environment where problems can develop.
You’ll also need to properly space support posts. The distance between support posts depends on your beam and joist sizes, deck height, and expected loads. The distance between posts affects your deck’s structural integrity because excessive spacing will cause deck sagging that may lead to structural collapse if too much weight is placed on the deck.
Mistake #3: Using Inappropriate Materials for Your Climate
Not all decking materials are created equal. What works in one climate may fail spectacularly in another.
For wood decks, using untreated lumber for any structural element is a recipe for disaster. Pine, fir, and other softwoods will rot quickly when exposed to moisture. Even for non-structural elements like decking boards, using appropriate materials matters. Cedar and redwood offer natural rot resistance but require regular maintenance. Pressure-treated lumber provides good durability but needs proper finishing to prevent cracking and splitting.
Composite is always the way to go, though (more on that soon).
When it comes to fasteners, using interior-grade hardware is another common mistake. Deck screws and bolts must be rated for exterior use and, ideally, corrosion-resistant. Standard construction screws will rust and fail, potentially causing boards to come loose or creating safety hazards.
Let Us Help You Avoid These Mistakes.
Mistake #4: Not Leaving Enough Gap When Installing Composite Materials
Composite decking has gained tremendous popularity, and for good reason — it offers the look of wood without a ton of maintenance. You can’t beat it. It lasts for decades. It does come with its own installation challenges, though.
One of the most critical mistakes is ignoring expansion requirements. Composite materials expand and can contract more than wood with temperature changes. During summer installations, failing to leave adequate gaps between board ends can result in buckling when temperatures rise. Always follow the manufacturer’s specifications.
Joist spacing requirements are also typically tighter for composite decking than traditional wood. Using wider spacing can result in a springy, uncomfortable deck surface or even structural failure.
You’ll also need different fasteners with composite materials. Each manufacturer specifies particular fasteners and installation methods. Using incorrect fasteners or installation techniques can void your warranty and lead to other issues with your deck.
Mistake #5: Ignoring Proper Drainage and Ventilation
Water is wood’s enemy. Even composite decking benefits from proper drainage and ventilation. I’ve seen decks fail prematurely because builders didn’t consider how water would move around and under the structure.
Proper deck design includes a slight slope away from the house to encourage water runoff. The space between deck boards should be enough to allow water to drain through rather than pooling on the surface. For composite decking, manufacturer specifications typically call for specific gap widths that must be maintained during installation.
Ventilation under the deck is equally important. Stagnant air and trapped moisture create ideal conditions for mold, mildew, and rot.
Mistake #6: Railing and Safety Code Violations
Deck railings aren’t just decorative — they’re safety features. They have their own code requirements. Installing railings at the wrong height creates safety hazards and code violations.
Baluster spacing is equally important. Most codes require spacing no more than 4 inches to prevent small children from slipping through.
Handrail requirements are often overlooked entirely. Steps with more than three risers typically require handrails.
Mistake #7: Poor Fastening Techniques
Even with the right materials, poor fastening techniques can compromise your deck’s integrity and appearance. Over-driving screws can weaken connections and create unsightly dimples in decking boards. Under-driving creates catch points and potential safety hazards.
For composite decking, pre-drilling is often necessary to prevent cracking, especially near board ends. Many builders skip this step to save time, only to discover cracked boards that need to be replaced.
Mistake #8: Bad Board Layout and Cutting
Board layout impacts the appearance and structural integrity of your deck. Creating butt joints where two boards meet end-to-end on the same joist creates weak points and visual inconsistencies as boards expand and contract at different rates.
The solution is to stagger butt joints across multiple joists. Better yet, use breaker boards. These are perpendicular boards that look good and help eliminate problematic butt joints.
Cutting techniques matter too. Composite materials require different cutting approaches than wood. Using the wrong blade type or cutting too quickly can result in chipped or melted edges that look unprofessional and may void warranties.
Mistake #9: Poor Proper Surface Preparation
Rushing into deck installation without getting your surface materials ready is going to create an issue. For wood decks, this means ensuring lumber is properly dried and acclimated before installation. Installing wood with high moisture content can result in excessive shrinkage, warping, and cracking as the material dries.
For composite materials, surface preparation includes ensuring the substructure is completely level and properly spaced. Composite boards require precise installation over properly prepared framing.
Mistake #10: Underestimating Maintenance Requirements
Many homeowners choose decking materials based on their appearance and cost without fully understanding long-term maintenance requirements. Even low-maintenance composite materials require periodic cleaning and inspection to maintain their appearance and warranty coverage.
Wood decks require regular staining or sealing to prevent moisture damage, UV degradation, and insect infestation. Skipping maintenance or using inappropriate products can void warranties and lead to premature failure.
Quick Summary
Building a deck is a significant investment in your home and lifestyle. While the mistakes outlined here might seem overwhelming, they’re all preventable with proper planning, quality materials, and attention to detail.
If you want to be 100% sure you’re deck is built right, call us. We’d be more than happy to make sure everything is done to the highest standard.
We know local building codes and the materials that work the best on Long Island.
