Load limit for roof T@B 400 BDL

qhumberd

Hi all I was trying to use the search function but no luck to see if the roof will hold the load of an average person when doing cleaning/maintenance work? I do not want to cause damage so thought I would ask those with more knowledge than myself. I am considering installing a Maxx fan upgrade but could not see how to do it without putting my weight on the roof. How do others accomplish this at home?

Thanks

falcon1970

The TAB400 (and probably all the other TABs) are built around a welded aluminum cage.  The structural members running across the roof (from side to side) are spaced about 12" apart I think.  I doubt that even a large person on the roof would cause it to collapse, but I'm almost positive that you would cause the aluminum skin and the underlying foam insulation to compress.  How much would depend on how heavy you are and whether you were standing over one of the transverse members or between them.
In any case, I think it would cause damage of some sort if you got on the roof.

Sharon_is_SAM

Don’t kneel on the roof.  I know on the 320 owners have leaned in to change the fan.  Not sure how 400 owners have managed.

qhumberd

Sharon_is_SAM said:

Don’t kneel on the roof.  I know on the 320 owners have leaned in to change the fan.  Not sure how 400 owners have managed.

I was very hesitant to do more than lean out on the roof, but working on a fan like that is pretty awkward.

So how do Nucamp and the dealers work up there? Do they use a scaffold setup?

I have a 10 ft and 12 foot stepladder that I might be able to create some space with a board between them across the back of the roof. Or I could fall and not go camping for a while.

Denny16

Most service areas use a special ladder setup that arches over the top of a rig, allowing one to work on a camper top, without putting any pressure on it.
Something like this work stand ladder: https://www.aviationpros.com/tools-equipment/shop-equipment/man-lifts-platforms-work-stands/article/21088960/stepping-up-ladder-safety

You could use a 10-12 foot ladder to get up,to,the roof, and lay a piece of 1/2 or 5/8ths plywood (wide enough to lean on) that goes from one side to the other (8-foot long bit) and spread out your weight to the side rail frames.
cheers

Dalehelman

The 320s will definitely not I repeat not support weight even kneeling weight. If you must I suggest distributing the load with a 2 or 3 foot square piece of 2” ridged foam insulation. I suspect the 400 roof is the same as the 320.

simonseyz

@qhumberd you can change out the fan without going on the roof. Been there, will post how I did it later today.

ecstatic

simonseyz said:

@qhumberd you can change out the fan without going on the roof. Been there, will post how I did it later today.

I am interested in how you did this.  I want to upgrade the Fantastic Fan to a Maxxair Deluxe and am trying to figure out how I will reach the top exterior to scrape away the old sealant etc for the new install.

This is what I have been debating but it seems like overkill

simonseyz

Guys will post the hows when I get back inside tonight

Denny16

Looks like a 14th century castle storming rig.  
cheers

simonseyz

Ok, this is how I installed the Maxfax. It's worth the change over, cause you can run it in the poring rain!

              You’ll need basic tools, a drill and bits, ladder, a thin putty knife and some type of Irwin quick clamps. You will need Butyl tape and Dicor lap sealant (got mine from Camping World) also get Naphtha thinner (Home Depot)

               His is how I switched out my Fantastic fan for a Maxfan Deluxe in a Tab 400. I did not have to climb onto the roof and only worked off a ladder on the door side of the camper. You’ll need to remove the Fantastic fan trim and fan unit from inside the camper, disconnect the power and cover lift arm.  Working off a ladder on the door side, use a thin 1”-1.5” putty knife, push the knife under the flange, wiggle it side to side if necessary, push in until it stops, it will push in easy.  Now move the knife an inch or so over and push instill it stops, you’ll need to do this all around the door side, front and back of the flange. Now lift the flange up reaching over to the other side and cut free any tape and caulk. Now for the important part, I was able to work through the opening from inside the camper off a small ladder. Using a single edge razor blade, scrap the remanding tape and caulk off the roof and wash any remanding stuff off with Naphtha, it will come off easily with Naphtha.   Place the new flange in the opening and line up square from inside, using clamps to hold in place. From the door side ladder, drill holes under each of two metal clips that hold the fan, temporally install the screws, remove the clamps and from inside through the opening drill the opposite holes. Also, you will need to check the flange were the wiring to the fan is and notch or drill a hole in the plastic flange at that point. Now remove the flange, install Butyl tape and install the flange (check wiring) and install the four screws, at this point you can use the clamp to work around all of the flange to squish the tape down or install all the screws ( I did not ) Back through the opening run a bead of Dicor lap sealant around the flange, you can use painters tape if needed, also the bead only needs to be around ¼ inch, also add a dab to each screw hole. Now you can install the fan, wire it and check operation. You’ll need to cut the inside trim ring to 1 ½ inch and install……. And that’s it!

 

BrianZ

@qhumberd, when I installed a fan cover, I used a 16' aluminum extension ladder, extended most of the way & leaned over the edge of the roof, with padding (carpet/foam pad) over the edge of the roof under the ladder, so that weight is supported by the wall.  Then, I used an 8ft stepladder next to the trailer to climb up & onto the extension ladder (on top of which I placed a strip of plywood & padding to lay on).  This allowed me to hang my arms over the end of the ladder above the fan vent.  You must be careful not to get too far out, otherwise you may experience the teeter-totter effect; but not to worry, because it's self-correcting when the foot of the ladder raises off the ground & slides farther away from the trailer, falling back to the ground. 😉 
For washing & waxing, I just use the 8-ft stepladder next to the trailer and a light weight aluminum painter's pole fitted with a double headed cleaning brush/soft pad found at Lowes I believe.
I think it may have been Verna who mentioned the extension ladder - not my idea, but works for me.  I weigh around 200, and no I'll effects on the T@B.
Edit:
Here's the brush I use..
https://tab-rv.vanillacommunity.com/search?adv=&search=pole-mounted+brush

ecstatic

simonseyz said:

Ok, this is how I installed the Maxfax.......

Thanks for the details!  I'm going to give this a try, much more comfortable doing it partially from the inside.