Observation on the NL/Bigfoot Clamshell Design

[whizbang]

I am starting this post because I don't want to hijack the other NL delam thread.

The NL/Bigfoot "water proof" clam shell design is especially appealing here in the Pacific northwest. I seriously considered both brands when we were shopping for a camper 13 years ago.

I remember finding a NL about an hour north of us. In the course of looking it over, I climbed up on the ladder to take a peak at the roof.

Holes. Holes. Holes. The ladder and "luggage" rack attached to the roof in 7 or 8 places. There was a plumbing vent, a refrigerator vent, roof vent, skylite, escape hatch, and, of course, front, rear, and side clearance lights. All holes appeared to be caulked with Dicor or something similar.

What's the advantage of a water proof design/structure if the water proof surface is pierced in 20 places and relies on conventional caulk to keep the rain out?

[Reddog1]

rhode trip wrote:

Reddog1 wrote:
I think it is much less expensive and time consuming to simply stay out of the trees.
Wayne

Ha,ha. I'm in New England...that's like telling you to stay out of the sun! :B

Well you should at least crank the Batwing antenna down, I did not. :B

Wayne

[rhode_trip]

Reddog1 wrote:
I think it is much less expensive and time consuming to simply stay out of the trees.
Wayne

Ha,ha. I'm in New England...that's like telling you to stay out of the sun! :B

[covered_wagon]

dunegoon1 wrote:
I had a problem with a leak around the sewer vent on my Bigfoot. The ABS pipe exits the roof and there was a gap around it. The vent assembly consists of a cone that is screwed down to the roof fiberglass and a silly cap that can easily be knocked off. When the cap is gone, rain enters and fills the cone until it can run down along the vent pipe. My solution was to clean all of the moss and water out of the cone, dry it all out, and then spray foam the gap around the vent pipe. I thought about filling the whole cone with foam sealer, but decided instead to drill a drain hole in the cone at the low corner. I can always fill the entire cone later if needed. I recently found a more rugged vent cap that is held in with spring wire. The second vent, for the gray water venting, was also modified likewise.

Oh. The water leak ruined the wood that supported the jack at the rear corner. But that is another story.

I added an ABS straight coupling (cut off the stop so it would slide/ sleeve down) to increase the size of the pipe with the size hole drilled thru the roof and caulked.

For pipe protection I covered each one with West Marine SS. clamshell vent covers.

Not that my way is better just the way I did it.

[dunegoon1]

I had a problem with a leak around the sewer vent on my Bigfoot. The ABS pipe exits the roof and there was a gap around it. The vent assembly consists of a cone that is screwed down to the roof fiberglass and a silly cap that can easily be knocked off. When the cap is gone, rain enters and fills the cone until it can run down along the vent pipe. My solution was to clean all of the moss and water out of the cone, dry it all out, and then spray foam the gap around the vent pipe. I thought about filling the whole cone with foam sealer, but decided instead to drill a drain hole in the cone at the low corner. I can always fill the entire cone later if needed. I recently found a more rugged vent cap that is held in with spring wire. The second vent, for the gray water venting, was also modified likewise.

Oh. The water leak ruined the wood that supported the jack at the rear corner. But that is another story.

[Reddog1]

I think it is much less expensive and time consuming to simply stay out of the trees.

How can I or anyone else make an excuse on my ripping off my Batwing? If you leave it up, and driving off, does that not fall under stupid? You can't fix that, but must repair it. Then again, maybe a manufacture flaw in design.

Wayne

[covered_wagon]

rhode trip wrote:

covered wagon wrote:
I did not like all the roof penetrations also, so I removed the luggage rack, which would have torn up the roof fiberglass if I ever hit a branch, sealed up the holes and removed the plastic pipe vents by putting steel protectors over the pipe vents. I bit more aerodynamic too I guess.

I ripped the luggage rack off on a tree branch, so I filled the holes with Marine-Tex and was done. I had problems with the forward vent breaking on branches after removing the luggage rack that offered some protection, so I made an aluminum limb-riser to protect it. I haven't had a problem since.

Good idea and good work too.:)

[HMS_Beagle]

The fiberglass roof is also a more stable surface to caulk against than many alternatives. On a fiberglass boat, removing and recaulking all the deck hardware every 10 years would be considered a very aggressive preventative maintenance schedule. Many go 15 or 20 years without much attention. The typical RV recommendation is to pour Dicor over it once a year. My BF camper purchased new in 1998 was sold in 2012 without a leak and no resealing since new. The one I have now is 8 years old, no leaks, no resealing from new.

[jimh406]

Reddog1 wrote:
My roof was installed over 27 years ago. Does anyone think a rubber type will survive that long? It has never leaked and only recaulked 3 or 4 times.

Yes, I do. I think the weak point is actually the caulk.

In any case, it's hard to compare when the weather in each area is quite a bit different.

[Downwindtracke1]

I would rate construction methods as 1) fiberglass clamshell,2) Styrofoam sandwich with aluminum framing, 3) Styrofoam sandwich with wood framing, and 4) the good? old stick and tin. Ease of repair would have a very different order. I shied away from a BF in my price range as interior repair, yes, the roof can leak, would be too much work.

[Reddog1]

I have never ripped off anything from my roof except a Batwing. It does a lousy job tree trimming. I have a scratch in the side of my Bigfoot from a limb on a very narrow road. Had my Bigfoot been anything other than molded fiberglass, it would have been ripped open and require major repair work.

Fact is, a big enough limb can clear the top off any TC. The difference the molded fiberglass is a lot tougher than any other roof on TC that I am aware of. My roof was installed over 27 years ago. Does anyone think a rubber type will survive that long? It has never leaked and only recaulked 3 or 4 times.

Wayne

[whizbang]

Yup. I was bored.

And yes, I have to agree that the NL/Bigfoot design has far fewer edge seams to leak.

[rhode_trip]

covered wagon wrote:
I did not like all the roof penetrations also, so I removed the luggage rack, which would have torn up the roof fiberglass if I ever hit a branch, sealed up the holes and removed the plastic pipe vents by putting steel protectors over the pipe vents. I bit more aerodynamic too I guess.

I ripped the luggage rack off on a tree branch, so I filled the holes with Marine-Tex and was done. I had problems with the forward vent breaking on branches after removing the luggage rack that offered some protection, so I made an aluminum limb-riser to protect it. I haven't had a problem since.

[covered_wagon]

I did not like all the roof penetrations also, so I removed the luggage rack, which would have torn up the roof fiberglass if I ever hit a branch, sealed up the holes and removed the plastic pipe vents by putting steel protectors over the pipe vents. I bit more aerodynamic too I guess.

[mkirsch]

Without the roof penetrations, what you'd have is a stinky, stifling, boring, deathtrap.