A DIY Roof Rack Make your Small Car Carry Big Stuff

A DIY Roof Rack Make your Small Car Carry Big Stuff

Editorial Note: Ive noticed that the blog has been getting a bit fluffy and lifestyle-designey in recent weeks, so its time to bring things down to Earth a bit with some practical stuff. Today I share a useful little project from back in the summer, and meanwhile, I just finished adding a big solar gain window to my house, which will make a nice upcoming post as well.

The previous MMM car a 2004 Subaru Impreza wagon. Those stock roof rails allowed either bikes or large pieces of lumber to be carried easily on the roof.

So youve got a small car now. Its a hatchback or wagon design, which allows you to carry bulky stuff as well as people. Thanks to that nice open interior space, you find you can easily carry 8-foot 2x4s home from the building materials store, as well as dressers and small appliances. Good for you!

But thanks to Mr. Money Mustache and other positive influences, youre getting more into home renovations and maintaining your own stuff these days. And unfortunately that means carrying much bigger things home. 48 sheets of plywood and drywall. Windows and doors. Long pieces of baseboard and trim. Even the occasional ladder, canoe and kayak.

Long ago, we covered some ideas on turning a little car into a big one. One of the tips was the idea of using a roof rack and optionally a roof box to expand your cargo area. But the problem with commercial roof racks (Yakima, Thule, etc.) is that they are designed for sports equipment and not building materials. Thus, they are typically very short. To carry long items without having the wind whip them around, you need a longer rack.

From about 2006-2011, I had the pleasure of hosting a golden old work truck that a friend lent me because he didnt have space to store it. It was a 1984 Nissan compact pickup, rusty yellowish-brown in color, and it went by the name El Amarillo.

Although it had only a 6-foot cargo bed and about 50 horsepower of output from its old rattly engine, boy could that old truck do some work (and it still can to this day!). But in my house-building work I often had the need to carry 16-foot pieces of lumber and even 24-foot sticks of steel for welding projects. Neither are practical with any size of pickup truck without modifications.

Heres the Amarillo in 2005 BEFORE I welded on a roof rack and used it for five years. (It still looks just as good and runs like a champ today).

To solve this need, I built a 12-foot long roof rack for the Amarillo out of steel. It hung out a couple feet over the back of the truck, and extended all the way over the bed and the cab, hanging out  well above the windshield. With a 12-foot rack, you can carry 24-foot material with a tolerable 6-foot overhang at each end, making it stable enough for a careful trip home from the metal store. And of course, carrying 16-footers and 4x8s with this rack was effortless.

In 2011 however, I returned the Amarillo and bought my current work van, a 1999 Honda Odyssey minivan.  In most departments, it is a big upgrade: the three rear doors allow much more efficient loading, and the 160+ cubic foot cargo bay can hold some massive stuff (50 sheets of plywood fit easily, for example). And it locks up and keeps everything safe from rain and dirt. But I still havent gotten around to making a real lumber rack for the new van. The Amarillo was old enough that my friend didnt mind me welding things right to the body. With the van, I will need to put a bit more finesse into it.

But that doesnt mean I cant carry big materials yet. This van, just like many smaller wagons and hatchbacks, came with roof rails. These are usually hollow aluminum tubes that are formed to the shape of the car and attached at several points. They are not much use by themselves, but they provide a base to which you can attach commercially-made crossbars, which can then hold accessories for skis, small kayaks, or mountain bikes. But those crossbars still doesnt help us  carry big lumber.

Luckily, there is an extremely easy way to convert a roof rail system to a big rack system. And without the sometimes-major expense of a commercial roof rack. You just need to custom-fit your own rectangle of sturdy wood and strap it tightly to the existing roof rails.

As it turns out, I had to do exactly that to my own van this summer. My cottage construction project got to the point of baseboard installation, which is best purchased in the longest lengths possible. I was faced with the need to transport about 500 feet of long boards (in 14-foot lengths) along a 30-mile winding and high-speed journey through the Gatineau mountains of Quebec to get them to the cottage. I didnt want to do that with them hanging 6 feet out of the vans rear hatch, and I didnt want them to blow off in the wind. So I simply spent about 15 minutes screwing together some scrap wood to come up with the following contraption:

Top rear view of the homemade rack

If you look closely, you can see that I just had to snug a pair of 1×5 boards (2x4s work too) to the inside of the existing roof rails, then screw cross-pieces to each end of the rails to create a rigid square. Then, you can just use straps or bungees to attach the rack to the car/van, and leave those attached as long as you need the rack in place.

Strength is no problem with a rack like this through the natural flex of the wood, it automatically distributes the weight right along the interior frame of the cars roof, which is located at the outside corners right under the stock roof rails. I have carried up to 500 pounds on racks of this style without adverse effects (although the cars cornering is affected by a top-heavy load, so take it slow).

If you care about the paint job on your roof (on my construction van, I generally do not), you can wedge bits of cardboard or carpet under the wood frame, or even attach permanent pads to the wood with hot glue before setting the rack in place. Heres a front view of the rack, strapped on with a ratcheting strap, and padded at the front by cardboard.

Front view

At this point, after a full 15 minutes of effort and perhaps $10 of supplies, you have a rack long enough to carry 16-foot material. Heres how I attached the baseboard to my new rack:

Side view a huge bundle of 14 foot baseboards, easily secured to factory roof rails with no rack.

Since I needed this load to survive speeds of up to 65MPH, I deliberately biased the loading towards the rear. When youre driving at highway speed, there is a huge wall of air rushing upwards over the windshield. If you leave long floppy pieces of wood in this wind river, they will get pulled upwards and possibly even broken. Tailing from the rear, on the other hand, the lumber gets a smoother ride in the slipstream.

Tech Tip: The absolute key to safe carrying of lumber and other big stuff is ratcheting straps. They look like this and you should be able to find a 4-pack of them at Home Depot/Lowes (Husky brand or similar) for $15-$20. You dont want to mess around with rope, string, tape, or even bungee cords except on the slowest and shortest of trips. This type of strap allows you to make a much tighter connection than even the strongest sailor could do with fancy knots and a rope.

The trip was a success, and I even saved the rack in a safe place so it will be waiting for me when I continue working on this cottage next summer. More importantly, I hope this plants an idea in your own head about ways to carry cargo without resorting to a pickup truck. When you buy a small hatchback or wagon for your next car, look for the presence of roof rails as an important added bonus.


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