Three walls, hold the floor
What you need to know before you start building a boathouse
As far as cottagey icons go, boathouses rank right up there with canoe Paddles, s’mores, and loons. Which is odd, really, because these waterfront garages, whether grand or utilitarian, are actually a rarity on the lake scene, with most cottagers making do with a regular dock or a sandy shoreline to park their boats. Sex appeal probably has a lot to do with all the attention: The fanciest boathouses are certainly lovely to look at in their multi-storeyed splendour, with architectural flourishes worthy of Sir Christopher Wren. They hog the spotlight because we’re all suckers for copper cupolas and ornate dormers.
But a boathouse doesn’t have to feature any of those fancy details, and can be as simple—or as complex—as you choose. In fact, the above-water design options for a boathouse are almost limitless, because once a solid foundation has been established, boathouse construction is pretty much the same as building a house on dry land, where interior finishes, windows, siding, and roof materials can be whatever your heart desires and your budget will tolerate.
Before you dream about what kind of boathouse you’d like to have, find out what kind you’re allowed to build. Bylaws vary widely from one municipality to the next (and even among different lakes in the same township). Some jurisdictions allow two-storey boathouses with living quarters above, some only accept single-storey boathouses, and many expressly forbid boathouses, period. Where new boathouses are allowed, their height and size—and how much shoreline they occupy—is tightly controlled. Visit your township office or talk to an experienced contractor well before the design process gets going.
Because most municipalities insist that boathouses and boatports must be designed or approved by a structural engineer before a building permit will be issued, you don’t need to become an expert on engineered trusses or laminated-veneer lumber to make sure your boathouse won’t collapse. But you should consider the number and size of the boat slips you need for your current—and future—flotilla. Rather than tailoring slips to specific boats, create one or two oversized slips that will give smaller boats lots of room to bob with wave action yet still be able to accommodate larger vessels in the future. It’s a balance between creating maximum mooring area and leaving enough interior dock space to comfortably access watercraft, store extra gear, and maybe set up that boathouse poker table you’ve always wanted.
A modern boathouse can easily support run-of-the-mill cottage runabouts lifted out of the water for winter storage, without any major modifications, but large or heavy boats may need special engineering. More critical, from a builder’s perspective, are the devices you might use to get those boats out of the water. Will boats be winched up and slung from overhead, or do you prefer to use a marine railway or a boat lift? If you plan to store small aluminum boats on the decking or on beams laid across the slips, how will they be lifted and swung? If the hoist system you want requires special supports or gets in the way of a garage-style overhead roller door, the building plans—or the doors—will need to change.
Other boathouse features can have spinoff effects. While running electricity, water, and sewer service into a boathouse isn’t a big deal, your cottage’s electrical service and septic system must be up to the job. Ignore these details at your peril, because a building inspector will not.