Posted 2011-05-17 4:58 PM (#134192) Subject: How do I determine roof strength for hayrack?
Member
Posts: 48
I'm looking at someone build me a hayrack, mainly so I can put a water caddy up there. Of course the 48 gallon caddy will contain roughly just under 400 pounds of water. I don't want my roof to be stressed. Any good rule of thumb or do I need to call the manufacturer for their recommendations?
Posted 2011-05-17 9:56 PM (#134195 - in reply to #134192) Subject: RE: How do I determine roof strength for hayrack?
Expert
Posts: 5870 Location: western PA
Like Paul says, the weight is applied to the wall tops, not the roof. The hay rack will have to support whatever weight you plan on carrying, and in itself, be supported only by each side of the rack. The supporting structure should start upwards at the wall and not just on top of the cove transitions. The wall studs are the best place to affix a secondary structure.
You should also allow a reserve carrying capacity of the rack, to take into account the changing vertical loads as your trailer hits bumps and such. 400# of water is a lot of weight at that height. If the tank does not have internal baffles, it may be too much.
Posted 2011-05-18 11:03 AM (#134197 - in reply to #134192) Subject: RE: How do I determine roof strength for hayrack?
Veteran
Posts: 229
arrestado, Your other option is narrower rack that is roof mounted. I purchased my Featherlite from a dealer who does quite a bit of fab work. They make nice hayracks with diamond plate floors in them. I had them install one of them in my Featherlite and also one in my Elite. They also install the 48 gallon half moon water tanks in the hay racks. They say that I was OK for both the water and the hay and I trust them. I haul out with a full tank of water and hay and have had no problems. I installed the tank on the Featherlite and they installed the tank on the Elite, just last year. I noticed on the install that they did not use straps, but instead used metal bands. They said that too many people store their trailers outside and that the straps were getting rotted and failing. If you want to see my hay rack and self install with straps, see ad number 299709. The hayrack appears to set on the roof bows, but it actually sets on angle irons which are bolted lengthwise on the trailer roof. If you want to see some detailed pictures of the rack as installed, see the link at https://picasaweb.google.com/100878032140884175593/FeatherliteTraile... Also, I second the info from Gard about the dynamics of water. I haul water with a 325 gallon tank in the back of a pickup. Once I hauled a tank that wasn't full. Never again. Now, even when I go out with the horse trailer, that 48 gallon tank is full and I make sure that it is empty on my way home.
Posted 2011-05-18 1:16 PM (#134198 - in reply to #134195) Subject: RE: How do I determine roof strength for hayrack?
Member
Posts: 48
Originally written by gard on 2011-05-17 8:56 PM
If the tank does not have internal baffles, it may be too much.
Thanks guys...Hey Gard, the tank that horsecamper has is what I was looking at putting up there. They are specifically designed for roof top. I doubt they have baffles in them. As long as it's full there and empty coming home, it should be ok?
Posted 2011-05-18 5:15 PM (#134206 - in reply to #134192) Subject: RE: How do I determine roof strength for hayrack?
Expert
Posts: 5870 Location: western PA
Horsecamper said it best. With a 325 gal tank in the bed of the truck, there was a problem with a partially empty tank. Remember that this was at an elevation of ~3 feet and could have weighed ~2700#. Your tank will be at an elevation of ~8 feet, and weighing 400#. Even though it weighs less, it will still have an affect on the stability and balance of your trailer when less than full.
The only way I would consider an unbaffled tank to be safe, is to use it absolutely full or empty. Start the day off with a full tank. When you're done for the day, dump the balance of the water from the tank, and you'll have no erratic surging problems.
How do I determine roof strength for hayrack?
