Mounting options for roof top tents
Scott has listed some of the more popular mounting options, which I can comment on, as we have several hundred tents in service in North America. I would also like to describe other options developed and used by AutoHome users for special needs. I am posting some photos of some examples. I will also limit my comments to mounting on pick-up trucks and trailers, as these fitments usually provoke the most questions and options.
A note on fuel efficiency:
Gas (fuel) mileage is often an issue. The best ways to minimize the impact of a tent on fuel consumption are; a.) employ a very streamlined tent, b.) Use a tent that is as lightweight as possible, consistent with long term performance, c.) place the tent in the slipstream of the vehicle - below cab height, or on a trailer.
Impact on mileage is very dependent on the type of vehicle that is employed, and how that vehicle is used. Example: an FJ40 Landcruiser, Land Rover series, or Jeep Wrangler is a 'brick' and somewhat under powered compared to other vehicles. Driven at lower speeds, as when in use on backroads and trails, the tent weight has more impact on mileage than the aerodynamics.
On highway mileage, traveling at speed, requires an aerodynamic solution. A traditional - folding, fabric - roof tent has a flat frontal surface of about 46" X 11" - 506 square inches of wind resistance at work. And the effect of this surface increases as the speed of the vehicle increases. This type of tent will have a penalty of 2 to 4 MPG or so, depending on a variety of factors - weigh, horsepower, altitude, etc. I prefer to use this type of tent on my trailer.
A streamlined, hard shell tent with a slick surface is many times more efficient. I have found that a tent like the Maggiolina AirLand has LESS impact on fuel efficiency than the roof rack alone - less wind resistance. To tell the truth, this type of tent on my Landcruiser or Ford Expedition is effiecent enough that it is hard to quantify the small impact on the mileage. On a lower powered vehicle, it becomes more noticeable, but is seldom more than 1 to 1.5 MPG penalty.
On mounting tents in general:
We much prefer tp recommend engineered aftermarket rack systems over factory or home made mounting systems. Thle and Yakima KNOW roof rack systems, and test configurations that are published in their fitment guides.
Bear in mind that factory rack systems may seriously limit the carrying capacity, or impose limits on durability under extreme conditions. We recommend that you fit your vehicle with aftermarket engineered rack system, such as Thule or Yakima.
Roof Rack System Load Ratings:
AutoHome roof top tents are designed to mount simply on engineered aftermarket crossbars, the same as you would use to carry your canoe, kayak or bicycle. The rack system transfers the weight to the structural parts of your vehicles's roof.
Like vehicles, roof racks carry a dynamic weight rating, which defines the tested limitations of the rack system when the vehicle is in motion. Most racks (in the USA) carry a maximum 165 pound dynamic rating, which means the rack can support 165 pounds of weight while driving down the road. AutoHome roof top tents weigh between 95 and 155 pounds, so the rack system can easily handle the weight. When you are parked and camping, this is a "static load", much more gentle and the racks can easily handle the additional weight of gear and occupants.
Off road Use: These tents are made to withstand a lot of abuse, but we highly recommend, when mounting a tent for off-highway use, that you employ THREE or more cross bars. This helps to distribute the load evenly under extreme use conditions.
Scott's tent mounting options:
1. Custom platform at bed height - I am not fond of this option, as it severely limits access to the bed and contents. It is strong and has limited impact on vehicle handling.
2. Custom Cage to mount tent at cab height - This option is often very similar to mounting on a 'lumber rack' a popular option that allows flexibility. I would place mounting to an 'exoskeleton' in the came category. Here is a photo of Gary Kardum's FJ45 trayback with a Columbus tent fitted to the exoskeleton.
3. Custom Cage to mount tent top even with cab height - a good functional option, but 'custom' _ $$, and the engineering must be solid, so that no functional problems ensue from the mounting structure. Desertdude chose to mount his Maggiolina this way, and it is a very tidy and workable arrangementHeres a Tacoma with this type of mounting:
4. Mounted to shell - This is a very simple and effective way to go. Most of our customers who mount tents to their pick-ups opt for this solution. Mounting to the shell does not need to be an engineering project. Most shells can be fitted with artificial rain gutters, standard cross bars, and the tent secured to the cross bars with standard mounting hardware. Here's two examples:
5. Mounted to hard tonneau - Problem is opeing the tonneau cover without some serious gas ram upgrading, and the tonneau cover really limits what can bo done. We don't see this otion very ofetn ofr these reasons.
6. Simple mount to load bars - Simple, effective, flexible. A no brainer when combined with a cap or extended cab system..
7. Mount to Thule Xsporter - We like the Xsporter a lot. It is very strong, adjustable for height, and can be bought off the shelf. Quite a few of our customers use them.
8. Mount above cab - This may look a little weird, but more than a few of our customers do this, and report that it works well. This really works best with a extended or double cab truck. Standard roof rack systems are employed. Here's a photo of a couple of Maggiolinas mounted to the cabs of Toyota trucks -
I have also seen customer engineer systems that allow the tent to slide to the rear on tracks - providing a sheltered area at the rear of the vehicle. I have seen them mounted in the bed of a Unimog, on motorcyle trailers, etc.
I will try to do a post on tents on trailers.
Mike S
