Trailer Deck Additional Questions

[TwinCreek]

I posted earlier about putting a new deck on a utility trailer. My trailer is 7' x 14' and I will be using pressure treated 2 x 10 x 14 ft boards. My question is how many rows of bolts and how many bolts in each board? I will be using galvanized 3/8" carriage bolts and the ends of the boards will be held in by the trailer frame. Thanks for your help!

 

[T.R.K.]

I don't understand the part about "how many rows". It would seem to me that you would put bolts in every cross member.

I would put 2 bolts in each cross member. About 1" from the edges. You can calculate by the number of cross members you have.

Knowing how much treated lumber likes to twist, I would look hard at using no more than 6" wide boards, if I were doing that job myself. Yes, I know its drilling a lot more holes, but I think the finished job would be worth it.

 

[TwinCreek]

I am thinking 2 bolts across per board and bolting to every other crossmember. Just seems like a lot of bolts.

 

[Albert Goerzen]

I would use self drilling/tapping/countersunk screws. A good 3/8" drill will drill them in quickly. I think they are available in #10 or 12 sizes, use two per cross member on a 2x6 or three on a 2x10. Run them in until they are just flush with the top of the plank, if you go deeper the water will sit in the recess and rot the board. Same goes for carriage bolts if you decide to go that way.

 

[huntingreen2day2]

I would use deck screws and if the boards are not fully seasoned 1 screw right in the center of the board at each cross member.I don't want the boards shrinking and splitting like they might if you use 2 screws and put them near the outside edge.

 

[pete black]

My 16 ft. trailer was redecked 16 years ago with 2x10x16 treated pine and has held up extremely well, although it is kept in a covered shed. My is designed to not utilize any fasteners,the forward end has a slot the wideth of the trailer as well as the rear. Theses slots accommodate the thickness of the board. The rear has a opening on one side to a allow the 2x to slip in and then just slide the board to the far side. Continue till area is full then a plate is welded across the open slot to hold them in place. 16 years a later the boards are still flat.

 

[ObsoElitist]

It depends on the design of the trailer. My 6 ton used planks crosswise, bolted twice on each lengthwise frame member. My 3 ton uses planks lengthwise trapped by angle irons welded on the ends and no bolts at all.

 

[PJH]

A few years ago, a friend put a new deck on his light trailer. It was made so the ends of the boards were trapped at the front and rear of the trailer. One of the boards bowed up in the center later, and he added bolts through only one of the center cross members to hold them down. I wouldn't think you'd need to bolt them at every cross member. I bolted every other cross member in my stock trailer. No problems (so far).

 

[Dick L]

I have a 20 foot and a 16 foot trailer with the 2" X 6" treated and both are only held by the ends without bolts in the boards. Just a metal lip over both ends. I never had them lift in the center. I broke a board on the 16" trailer and all I had to do is remove the rear retainer, slide the old board out and slide the new one in.

 

[Bryan inIowa]

Mine is 16 ft , 2x8 no bolts,held in by ends only . No need for bolts of screws unless boards are bowing up , which I have yet to see .

 

[MikeinKy]

I have one that I built about 25 yrs ago that is 16' long and I have both ends of the boards trapped and two rows of bolts. One each about a third of the way from each end. I used floor screws like is in a semi trailer, it is easier and quicker. Drill a hole from the top and the screws are self tapping and they are not very expensive. They have tapered heads and are flush with the floor.

 

[jon f mn]

The number of bolts depends largely on how your trailer is made. Some trailers rely on the floor for structural integrity so more bolts are needed. Some only bolt on the ends or not at all, this is so they can sell the cheaper. One thing is certain, the more bolts you put in the less flex you will get in the trailer frame. When I build a trailer I put 2 bolts in each end and one bolt in each crossmember on alternating sides of the boards. This keeps all the crossmembers and planks working together and with the alternating sides keeps the planks from twisting. Depending on what you get for treated you could get significant twisting. If you live in the salt belt either used 1/4" trailer decking screws or 5/16" regular bolts. Anything smaller can rust out especially with treated wood as the new treating methods are corrosive to bolts. These are the deck screws I use and they work great, just drill a hole a hole and run them in. With treated lumber they tend to sink in a lot tho and on some boards I've had to use a washer.
Deck screws

 

[jon f mn]

With 2x10 boards you may want to put more screws than that in, I usually use 2x6 or 2x8 boards

 

[Butch(OH)]

As they said depends on the use. My 16' landscape trailer has 2x8 pine deck and nothing holds the deck down other than one screw at the rear end. The front end of the planks go under a welded 1/4 x 2 strip that is over the top of the front cross member. 10 years old and never a problem but all it hauls is lawn mowers and light stuff. For heaver usage we have quit using bolts and use 5/16 self tapping trailer deck screws that John and others mentioned.

 

[Geo-TH,In]

Helped neighbor replace the treated wood on his 7x16 trailer. Only had one bolt in each board at the front. At the rear the boards slipped in under a metal lip. My 20 ft implement trailer has 2 screws in every crossmember.

 

[Nebraska Kirk]

(quoted from post at 21:36:45 01/04/16) A few years ago, a friend put a new deck on his light trailer. It was made so the ends of the boards were trapped at the front and rear of the trailer.

My trailer was made the same way. After replacing the deck a few years ago, I meant to put a couple of rows of bolts in the planks, but never got it done and since the ends were trapped, the planks could not come out. The planks did shrink and the middle one bowed some leaving a gap in the middle of the trailer, but they did not twist or cup. I just recently replaced the planks again, this time I used oak and since I could not get 20' oak planks, I used 10 footers. These I fastened down with galvanized carriage bolts, one row in the middle of the planks and a second row at the ends where the 10' planks join, so 4 bolts per plank.

 

[Dan in North Houston]

My 16' trailer has a pine deck with no bolts or screws. Front and back ends of the boards are trapped under an angle iron cross-piece. The deck gets a coat of paint about every 10 years, and has been stored inside the last 10 years. It is in great shape, no problems with it at all.

 

[dhermesc]

I have a 14' that had the floor replaced when I bought it. It only had a bolt in either end on a few of the boards - most just laid there (2X6s) - lip to hold it down. I but one 3/8 bolt on each end of the 2X6 with nothing in the middle cross sections and called it good.

 

[IAtractorKid]

Just replaced the deck on my gooseneck this past fall. 20' deck, boards fit under a lip on front and back, one row of screws in the middle of the boards. 2 per board (2x8s) of the Teks self-drilling screws.

 

[Charles in Aus.]

Bolts or screws aside , apply a fat bead of good quality adhesive sealant such as Sikkens between each board and cross member . Adds to structural integrity and prevents moisture from sitting there and causing mischief .