1. The Dock Stability Secret: It's All in the Legs
People always ask me if my dock frames are strong enough. Yes! Of course they are! Almost everybody's dock frames are strong enough! I'll bet that heavy old wood dock you have now - even with the pain it brings installing and removing every year - is still strong enough. But here's the better question: Is it stable and sturdy?
Back in the day everyone would always pound their dock legs down into the lake bottom every spring and then pry them out every fall. I'll never understand why they did this. I've personally stood on plenty of docks with pounded posts that would make you dizzy from the wobble. So what was the point of it all?
Here is the key: dock wobble is almost always a function of water depth or "height" of the dock. The deeper the water is, the higher the center of gravity the dock has. I often present it as the equivalent of being on the top rung of a step ladder. The ladder is very stable on the first couple of steps, but once you get up to the paint can rack you better start looking for a safe landing spot.
As the dock support legs get longer they are more susceptible to flexing. The amount they flex is very small, but over greater heights it can make for a shaky dock. It doesn't matter how far you drive your legs, or how strong your frame is, the legs will flex. So this is a real problem, and there are real good solutions to take care of it.
The first and easiest solution is to use 1-1/2" nominal sch. 40 aluminum pipe like we do. This pipe has an almost 2" outside diameter with a heavy wall thickness. This makes for stronger legs with less flex. Some companies use 1-1/4" legs. We certainly don't. Now you won't be fooled.
The second solution is to add cross bracing. In general, whenever a customer uses my docks in 4-5ft of water or more I start adding cross bracing. A cross brace is a bar that goes from one leg to the other rising at an angle. One side may be down near the mud foot and then rise at a 30-45 degree angle to come up to almost water level. What this does is provide accountability side-to-side between legs on a section of dock. That means one leg can't flex without bringing the other one with it. This makes a huge difference on your dock stability. Pepper in some cross braces on your deeper water sections and you'll have a dock you can be confident in!
2. Aluminum or Galvanized Steel – Which is better for docks?
So which is the better dock building material – aluminum or galvanized steel? Well I’m going to give you the old "Sunday morning politician on Meet the Press" answer. It depends.
But I’m not sidestepping the question to avoid being on the record - it really does depend! Each offers their own advantages and disadvantages. Galvanized steel consists of the base steel metal being dipped into a molten bath of zinc at temperatures that cause excellent adhesion. The resultant product is a very bright silver finish that will dull gray over the years. Because the zinc takes on a sacrificial status – meaning it actually corrodes in place of the base metal – galvanized products can easily last 20 years or more before troublesome rust begins to take over. It is important to remember that paint is not a sufficient substitute for galvanizing, as it only provides a barrier to corrosion, not a chemical conversion.
So galvanized steel won’t rust (just like aluminum won’t), but what about the weight? That is where aluminum steps in and really shines. At roughly 1/3 the weight of a comparable section of steel, but with similar strength characteristics, aluminum is the clear choice for dock products. In the northern states of the US, ice formation on lakes and rivers can pose a serious threat to docks left in the water during the winter. Because of this threat, many lakefront owners are forced to remove their docks in the fall and put them back in every spring. This is no big deal if there is a ready and willing group of able-bodied workers willing to get the job done, but for homeowners not wanting to burden themselves or their families, other solutions should be considered. With its superior strength and weight characteristics, aluminum is the preferred material for dock hardware.
Of course, aluminum is typically more expensive than galvanized steel as it is a superior product. Is it a worthwhile upgrade? Use this simple method to determine that for yourself. Take the difference in cost of an aluminum product you’re considering over a comparable steel product. Then, divide that by the number of years you plan to use the product – in some cases 20 years or more. The resultant per year cost to upgrade may surprise you. Would you pay $20 extra per year to save 66% of the weight?
That's just smart math.
3. Do I Need to Remove My Dock for Winter?
This question is very common among first time lakefront home owners. The preceding scenario is usually as follows: "I just bought this house in June, the old dock is either gone or an accident waiting to happen, and I have NO IDEA what I even need, let alone want." Fear not my soon-to-be-lounging-lakeside friends, I’ve got all the information you need!
Perhaps the most important consideration when choosing a style of dock – whether it be permanent, sectional, floating, roll-in, etc. – is if you will need to remove it in the winter, or if it can stay in year round. In northern climates where lakes, ponds, and rivers freeze during the winter, the ice can create powerful forces that will wreck and remove your dock with ease. I have personally seen a number of docks and hoists frozen in ice 200 yards off shore that some lackadaisical lake home owner failed to remove in due time, perhaps a result of the prior summer’s borderline excessive lakeside relaxation.
If your lake doesn’t freeze and the water stays open all year, you should be fine barring some type of high water event. However, beware of moving ice sheets in the spring. Just because your part of the lake didn’t freeze, it doesn’t mean a cove around the bend didn’t. Large moving sheets of ice during ice out often pose the biggest threats. If you are on a lake that is fairly large in size (think square miles, not acres) but still freezes, you’re going to need to get them out. Ice will freeze and expand up onto shore crumbling your docks, or the ice will freeze around them and drag them out into the lake on ice out. Either way, you’re losing your stuff. Don’t bother with the usual tricks such as pounding the support pipes into the lake bottom or filling them with concrete as you are just making it harder for you to clean up the wreckage in the spring. Ice wins almost every time. The key is to instead have a dock that is easy to remove, whether that be from using light weight aluminum materials, removable deck panel designs, tip-in docks, or easy roll-in wheel kits.
To sum things up, when new lakefront owners ask me about removing their docks every winter I respond with one simple question. What are your neighbors doing? They’ve been there for years, and if they’re all taking their docks out every fall, you should be to. If they’re all leaving them in, there’s a good chance you’ll avoid the winter’s wrath.
4. Can I Tie My Boat to My Dock?
This depends on a number of factors such as lake conditions, size of the boat, and the dock you’re using. Let’s look at each factor individually:
Lake Conditions: If you live on a small lake or pond that receives minimal wake from boaters and wind you can usually leave your boat tied directly to the dock. However, if you are on a larger, more turbulent lake that receives waves and swells of over 1ft, you may find your boat has been pushing your dock around like the playground bully. In a big lake setting, it is best to only tie off for transient docking and also with the use of mooring equipment such as dock bumpers and mooring whips.
Size of the Boat: If you only show up to your cottage once a year, you could probably expect your aluminum row boat you tied up 4 months ago to still be there (assuming you can tie a quality knot). However, if you tie up your 36ft Chris Craft and leave for 4 months you may walk into the local boat livery only to find your neighbor a dozen cottages downwind discussing his great classic boat find. In other words, be smart about it. Consider the value of the boat and weigh it against the cost of a boat hoist spread out over years of use.
The Dock: Many modern residential docks are made of lightweight aluminum and with slick removable deck insert designs. They are lightweight by intent as to make them easy to install and remove in northern lakes. This is a double edged sword for a cottage dweller looking to tie their boat to the dock. A permanent dock or a much heavier dock will hold their position much better than one designed to be the lightest possible. Mix a lightweight dock with a heavy weight boat and you may find your dock laying on its side. If a hoist just isn’t an option, be smart about your dock layout. Adding a patio area to your dock can greatly increase your footprint in the water. You might also consider adding a set of auger posts - dock legs with screw tips mounted to them. Once your dock is installed, you can add the auger posts to your dock and screw them right down into the lake bottom. This gives your dock extra staying power at a very low cost.
To sum things up, for any boat other than the very smallest and lightest, it will always be best to use a hoist. However, if you're smart about it you can tie up confidently. My Advice: Save money on your dock by avoiding purchasing them from the marinas and maybe you’ll be able to afford that hoist.
5. Do I Need to Anchor My Dock to the Lake Bottom?
This is a very common question from first time lakefront owners. Their concerns are valid. These days many docks are made from light weight aluminum materials for ease of installation and removal. Dock frames and decking made of wood float in the water given the opportunity. Summer time thunderstorms kick up 2ft rollers at a moment’s notice. Add those factors to the need for some folks to tie their boat directly to their docks, and it’s a wonder how ANY dock can hold its position.
Anchoring a dock can be a miserable affair. One method is to pound support pipes into the gravel. This takes a toll on one’s back (or their friend’s backs if they are crafty enough to recruit help). Of course then you have to figure out a way to get the pipes out in the fall. You can’t pound up! Personally, I have no interest in doing work that doesn’t need to be done. You shouldn’t either.
As with many things in life, 1 design point is the source of most of the trouble and grief when it comes to docks holding their position all season long. On a normal, calm day, the only part of the dock that is in the water is the support legs. Because the support legs have a relatively low surface area in proportion to the entire dock, waves easily pass through without raising a fuss. This is the key. Many lake owners like to keep their dock surface so low to the water that even a normal lake chop rolls over the top, but these folks do so at their own risk. Because there is so much surface area on the wooden portion of the dock – and the fact that water is incompressible – waves hitting the underside of your dock is what will cause movement. It’s the same thing that keeps your boats afloat. Buoyancy! Therefore, my advice to cottage owners is to assess typical worst case wave conditions. If a nasty summer time thunderstorm will kick up waves that are 24 inches tall, keep your dock 26 inches out of the water. I had a customer install one of my docks on an eastern bay of Lake Ontario. When the hurricane that hit the northeast in fall 0f 2011 rolled through, his neighbor’s dock tipped over and floated away – along with his boat. My customers dock held its position. The highest waves just barely touched the bottom of his decking.
For my customers, I recommend a simple mud pad outfitted to the bottom of your support pipe. This makes for easy installation and removal as the seasons change. No pounding and no frustration. If anchoring is absolutely necessary, use a couple of auger posts. If we avoid the problem, we have no need to come up with a solution. Easy Peasy.
6. Should I Use A Floating Dock?
Customers often come to me and say “Hey, I’d like a floating dock for my cottage.” Their request is understandable. Floating docks conjure up nostalgic images of those Adirondack camps and rustic boat launches we all hold dear to our hearts. The emotional appeal aside, when is it right to use a floating dock and when is it just added cost? There are 2 primary scenarios that drive the need for a floating dock: deep water and soft bottoms.
Across the country we have a very diverse variety of water types. From shale and gravel bottoms to slow moving rivers, the way your dock interfaces the water bottom is a critical design point that needs to be addressed early on in the dock selection process. Because the majority of the northern climates get locked up with powerful sheets of ice every winter, to leave a seasonal dock in the water is as good as leaving it out by the road for free. Kiss it goodbye. A slow drive along many frozen lakes will in most years feature at least one humbled homeowner whose dock has been dragged 300 yards into the lake by an unpredictable and ever shifting sheet of ice.
Because of these drastic weather changes, it is necessary to remove a seasonal dock every year. Seasonal docks can typically be broken into 3 main groups: leg docks, roll-in docks, and floating docks.
The first group, leg docks, feature either 2 or 4 leg posts that support a section of dock (typically 4ft wide by 8-20ft long). These docks have some sort of mud feet attached to the bottom of the support pipes which increase the surface area of the support pipes to better distribute the load and prevent the legs from wedging down into the lake bottom. Remember, this dock has to be removed at season’s end so the more that dock settles into the lake bottom, the harder it’s going to be to remove in the fall. Hence, the leg dock is an excellent option for gravel and slightly silty bottoms with no more than 12 inches of soft material.
You might also consider a roll-in dock. These docks typically feature 1 or more set of molded plastic wheels and go in just as the name would suggest. Pick up the end and roll it in like a wheelbarrow. For a lightweight aluminum truss dock or a galvanized steel dock with the decking removed, this is at best a 1 person job and the task can be finished very quickly. However, like the leg dock, if there is a significant layer of soft material, the roll-in dock wheels will sink in the mud and be a real hassle to remove in the fall. Sometimes a 4 wheel drive truck or a winch with steel cable is the only method of removal.
Now for the floating dock. I’ve personally stuck my feet into water bottoms 2 feet off shore that could swallow a man whole. When visiting a customer on a Lake Ontario bay in New York the bottom was so soft and mucky that it was literally underwater quick sand. Wheel a roll-in dock in there and it will never come out again . Pound the posts of a leg dock down with a sledge hammer and watch the ice manipulate your dock with ease every winter. This is the scenario where a floating dock can really shine. Cast aluminum augers are fastened to the bottom of the support pipes. The pipes are locked in an upright position and the dock is floated into place. Once in place, release the pipes from their upright position and auger them into the soft bottom just like a screw.
For the second application where one would use a floating dock we’ll investigate the deep water scenario. All things being equal, a leg dock will almost always be less expensive than a floating dock for the simple fact that dock floats are not being purchased. Floats typically run between $100 and $200 each depending on the supplier and shipping costs. At 2-3 floats per section, this cost adds up quickly. As a rule of thumb, I generally tell my customers that any water depth over 7 or 8ft would begin to dictate a floating dock as a necessity. There are a number of reasons for this. The first is that leg docks often become unstable with long legs. If the water is 7ft deep and the dock is 2ft above the water, all of a sudden your center of gravity is equivalent to a person balancing on the upper steps of a 12ft folding ladder. Not good. There are certain things to mitigate the effects of sway due to a high center of gravity, such as cross bracing, but the physics of the situation suggest you could be looking for trouble.
In addition to the sway issue, it is also worthwhile to note that if a dock is installed in a cold winter climate, it may be necessary to remove and install the dock seasonally to prevent ice damage. Remember, if your dock is in 7ft of water and you’re only 6ft tall, it could make for a tricky, if not dangerous removal and installation process.
7. Which Dock Layout is Best for Me?
So you’ve measured water depths, surveyed the neighbors dock, and identified how many 8ft long sections you’ll need to achieve maximum velocity and height when jumping off the end of the dock. This, my cottage dwelling friends, is your baseline. What you add on from there is what transforms your dock from a strictly functional piece of equipment to a living/entertaining area and much more.
Some people want just a plain straight dock, and that’s just fine. For our purposes, we'll assume you want something more. We add different layouts and configurations to our docks for 2 main reasons – extra living space and increased access to watercraft. Allow me to elaborate on both needs with some of my favorite dock configurations.
Extra Living Space:
In my experience as a dock builder this is the greater of the 2 needs for adding dock space. Most folks would rather invest their funds in extra space for living rather than extra space for functionality – which the dock inherently has anyway being that it gets you from shore to boat. For my customers, 9 times out of 10 the dock layout of choice is the patio dock. This dock consists of taking an additional section of dock and placing it parallel and next to the last section. Adding 1 patio dock essentially creates an 8ft x 8ft living area on the water (assuming 4ft wide x 8ft long sections). By adding a 2nd patio dock, you now have a 12ft wide x 8ft long area. This can go on for as long as is needed. The real advantage of this layout is that all the space is useable. By adding even 1 patio dock section you would have enough room for 2 Adirondack chairs and space for someone to cast a lure in front of you. I’ve seen people put whole patio sets on their patio dock.
Another great option is the "T" dock configuration. The idea here is to take the last section of dock and invert it 90 degrees and center it (like a T). While there isn’t as much useable space as the patio area, there is still enough space for 2 individuals to either sit or stand and cast for some fish. The tee configuration is one of the most classic dock layouts and a snapshot of your dock at dusk or dawn could look like it came straight out of an L.L. Bean catalog (minus the masculine guy in his long johns sipping coffee with his retriever – but hey, that could be you!)
Dock configurations that address access to boats and jet skis vary widely and tend to be mostly a reflection of what the cottage owner needs for mooring. A common layout for this need would likely be the courtesy dock. This configuration consists of two shorter lengths of dock shooting off the side of the main dock to create docking bays. These docks are usually in the 12ft to 20ft length and are sometimes narrower than the main dock. How the courtesy dock configuration got its name eludes me, but I suppose if I were boating across the lake to a friend’s place and they had a nice docking bay all set up for my mooring pleasure, I would indeed consider them to be quite courteous.
The bottom line is you need to identify what exactly it is you want from your dock, and then work the best plan to achieve it. Use quality materials and good design and I’m sure you’ll be pleased with your decision.