Carry sheet goods on car roof

[DigitalM]

Here's a cool idea from youTuber Dan Pattison.


Is this legal in the UK?

Of course, I get it – it's safer to get it delivered, you shouldn't drive home at 200mph over bridges into a crosswind and this would be stupid on a tiny SmartCar and all those considerations. I've got a sturdy Toyota Rav4 with 100kg rated roof bars. I could do with carrying the odd sheet or two from time to time (much less than 100kg).

I wondered if anyone else is doing this, or has any better suggestions?

 

[gmgmgm]

I've driven short distances many times with sheet goods on the roof, just buy a couple of 4x2s at the same time to give it strength, do several sheets at once (for added strength) and add a lot of ropes / ratchet straps. It helps having an estate car, so there's minimal overhang, and stick to slow roads. 60mph winds will lift/bend single sheets easily, but a mass of plywood is pretty strong. Don't buy "odd sheets", always buy a few at a time.

I'm not sure on the legalities, but I certainly wouldn't try taking a single sheet of ply on a Fiesta, but a stack of 8x4s secured sensibly on an estate car should be fine.

 

[Phil Pascoe]

Pulling out of the builder's merchant's I followed someone with a sheet of 6mm ply on his roof rack tied across the middle. I could see the front lifting so held back ......... it lifted higher and higher and bang! The front half of the sheet went about thirty feet in the air.

 

[pulleyt]

I made a carrier for my estate car. I started with a couple of cross bars of 50 x 30 maple. These have u-bolts to hold them in place as far apart as possible on the roof bars and are about 1350 long. I then made a 2440 x 1220 frame from 2x4 CLS including a middle 'rail's, i.e. Two 2440 stiles and three rails at (1220 - width of the two stiles). All butt joints but reinforced with 10mm dominos as well as glue and screwed. The frame is bolted onto the two cross bars with the bolt heads recessed into the top of the frame

I added 8 eye bolts on the underside of the frame, two on each stile and two on each of the outer rails. Once the sheets are laying on the frame I can use 4 ratchet straps to hold the sheets in place securely and i make sure my route home is 30mph speed limit or less all the way.

It only gets occasional use and, when not in nuse, I hang it on the side of the shed which has a canopy to keep off the weather. I'm confident that is is safe as long as I keep the overall load weight sensible. The only other consideration is choosing a dry day for collection.

And weather is why I prefer to collect over delivery. I have to break down give sheets to get them into the shed and I don't want a delivery when it's raining.

 

[shed9]

Obvious I know but in the context of securing several sheets at a time (for the purpose of rigidity) be mindful of weight limits. 18mm ply at 8x4 is going to be north of 32kg at the very least per sheet. It won't take many to reach and exceed safe limits and I'd also wager the insurers will have little trouble walking away from a claim concerning the safe transport of ply sheet that exceeds the footprint of the actual roof using ad-hoc home made methods.

Don't mean to wind up the safety-police siren, just stating the obvious. Not sure most people know the capacity of their car's roof / roof bars.

 

[Stigmorgan]

Pulling out of the builder's merchant's I followed someone with a sheet of 6mm ply on his roof rack tied across the middle. I could see the front lifting so held back ......... it lifted higher and higher and bang! The front half of the sheet went about thirty feet in the air.

I've seen the same thing, Estate car had a few sheets of (I think 18mm) ply with only 1 strap across the middle, doing about 30mph and the top sheet folded like a sheet of paper.

 

[Terry - Somerset]

We have all as children waved a hand in the airflow as dad drove at 50mph and felt the force that a small surface area at a modest speed can exert. As adults, walking into a wind of 30mph can be a struggle. At ~60mph you may be swept off your feet.

The potential surface area of a full sheet is many times that of an adult. On the leading edge, the force will act on an area of just (say) 18mm x 1200mm. But if wind and/or turbulence lifts the leading edge, the drag/force will increase.

Resistance to bending, and ultimate fracture depends on the material - eg: chipboard is more likely to fracture for a given force than ply. If the sheet does not fracture it may generate lift with adverse impacts on vehicle stability.

My amateur observation is that if sheet goods are carried on a roof they need to be:

• firmly secured to a rigid frame/roof rack
• particular attention paid to the security of the leading edge
• driven at modest speed noting that aerodynamic drag and therefore force increase with the square of velocity

 

[Sporky McGuffin]

If you set up your carrier so that the rear of the sheet was a little higher than the front, you could generate aerodynamic downforce, enabling higher cornering speeds and getting your sheet goods home sooner...

Not a serious suggestion.

 

[Phil Pascoe]

Many moons ago I drove a Volvo estate from Newport in Shropshire to W. Cornwall with a load of well over a ton, including a cast iron spiral staircase on the roof rack.

 

[baldkev]

I once came back from plymouth with a couple of 18mm ply on the van roof racks. By the rime i got near home i had forgotten they were there and at about 70, the front of the van lifted up and there was a loud bang...... then the van dropped back down and i stopped, to find the ply plus roof racks on the road behind me
It literally ripped the racks out of the metal gutter and bent it up..... so dont be a kev!

 

[Suffolkboy]

I once purchased some assorted items from B&Q including some drawer fronts from the bargain bin I was going to use for a project. I think there were eight in total.

Loaded my assorted items into my Fiesta van that I had at the time and began to head home.

I drove the small roads for maybe three or four miles, negotiating corners and roundabouts but as I reached 50ish on the slip road of a large A road I hear a weird scraping noise and saw eight pieces of wood flying about in my rear view mirror.

Luckily enough there were no cars behind me (thank god) and I managed to pull up on the hard shoulder and collect the drawer fronts.

Lesson learned.... Never EVER put anything on the roof of the car before opening the doors...

 

[DigitalM]

So the consensus seems to be, within reason and with care it's not a ridiculous thing to do (or similar).

Does anyone bother to try to cover the sheets with tarp or plastic when raining, or do you just shrug it off and let them dry once home? I guess it massively depends on the materials.

 

[baldkev]

Lesson learned.... Never EVER put anything on the roof of the car before opening the doors...

Yarp, last year i left a new stabila 6 foot level on my roof while i loaded the truck up. I never saw it again


These days i have a mitsubishi L200 and i carry a lot on the roof.

As long as it is well strapped down ( i always use ratchet straps because my knots arent particularly reliable ) and you dont drive fast, it should be fine. Worth pointing out i have 4 roof bars to strap to, just under 2.4m from front bar to back bar

 

[Gareth62]

Thin sheets at the bottom thicker sheets on the top then some timber on top and lock it all down with ratchet straps

 

[Myfordman]

Thin sheets at the bottom thicker sheets on the top then some timber on top and lock it all down with ratchet straps

I use several f clamps across the leading edge onto the front roof bar. It is vital not to get the leading edge lifting

 

[Orraloon]

Thing can always be overdone.
Express Log Delivery System, Crazy Canadian Woodworking - YouTube
Regards
John

 

[Stuart Moffat]

I used to fly gliders. It’s astonishing how slowly you can fly. A two seater with two people in it can weigh about a metric ton and not stall at 40 something knots. The wings are each longer than 8 feet but narrower than 4 feet. Perhaps one sheet for each wing to lift about the same weight as my car At 50 mph. just A thought!

 

[JefL]

On the rare occasions I collect full sheets I split my double extension aluminium ladders and fix them to the roof bars to support the sheet(s). Ratchet straps and lots of rope to ensure the sheets are well secured, paying particular attention to prevent the leading edge lifting. And stick to 30mph on the way home. This on a Landrover Freelander, never carried enough to be concerned about weight.
Jef

 

[slavedata]

I think I'll keep my collects to what I can get inside the car and get anything bigger delivered. I once started loading the car in B&Qs car park, found it wouldn't fit and went back in and bought a cheap saw. Problem solved.

 

[swisstony]

Been there done that and have to laugh about it now . Was insulating the shed with kingspan and had most delivered but needed 2 extra sheets so popped down to wickes and threw them onto my roof rack along with a sheet of ply . Strapped everything down, forgot about the leading edge and drove down the road . Going really slowly ( about 30 max ) and crack .
Stopped and found out the whole sheet had folded back on itself

had to drive home with one hand driving and the other holding the sheet

*****