Any Ideas to RepaIr Loose Ceiling on NLcamper?

Thank you HMSBeagle, I will do the testing and find some flexible XPS. I will need to cut the headliner along two lines because one edge of the loose panel will fold down giving the access needed and the other is at the outside wall. The headliner is boat headliner, stretches both directions, is available at West Marine and will allow me to make hemmed trim that will get hot glued to hide the cut line in the headliner.

This will be a great learning experience and may find some areas that will benefit from some spray foam between panels as they feel like there are some small gaps where the loose panel doesn't fit snug to the one next to it. Spray foam itself has an adhesive quality as long as you use it sparingly so as to not distort anything during it's expansion time frame.

You may be able to do a careful, straight knife cut around the panel that needs to come down and put it back without is being that noticeable. I don't remember the headliner in an NL but I think kinda like indoor/outdoor carpet?

The advantage of using new foam (beyond using better foam) is it starts clean with no old adhesive. The fiberglass can be cleaned even with very harsh chemicals, it won't be hurt by it (acetone, MEK, laquer thinner, etc.). The luan plywood will be a little more of a challenge but can probably be cleaned up. You should test whatever adhesive you are thinking of using, polystyrene of both types is quite chemically sensitive.

Cannon George wrote:
As warning/advice to others, need to ask did water entry from roof (lack of Dicor or other sealing on roof penetrations lead up to this? Understand delamination can occur for other reasons.

No leaks camper is tight but was camped in very cold weather for 2 months. Condesation began to build and show deterioration in other areas and various areas. Vents are serviced every 2/3 years and nothing let go.

HMSBeagle, I wasn't going to say it but, since you did I thank you. Also very good suggestion on the XPS.

covered wagon wrote:

notsobigjoe wrote:
what is bead board?

It is foam board or rigid foam insulation made of small round balls or beads of various sizes, usually around 1/8 inch in size that are formed together into sheets of various thicknesses of rigid foam board. Northern lite uses this for insulation because it is less rigid and will glue and flex onto compounded curves and shapes to insulate and strengthen the fiberglass shell. Keeping it lightweight.

I am a little more cynical - they use it because it is cheaper than something better. There are plenty of choices in structural foam that are much better than bead board for this application. They cost more. XPS costs only a little more, a PVC or SAN core (which is what would be used in a boat) costs quite a bit more.

If I was pulling down the ceiling for a repair, I'd put back XPS rather than EPS.

As warning/advice to others, need to ask did water entry from roof (lack of Dicor or other sealing on roof penetrations lead up to this? Understand delamination can occur for other reasons.

notsobigjoe wrote:
what is bead board?

It is foam board or rigid foam insulation made of small round balls or beads of various sizes, usually around 1/8 inch in size that are formed together into sheets of various thicknesses of rigid foam board. Northern lite uses this for insulation because it is less rigid and will glue and flex onto compounded curves and shapes to insulate and strengthen the fiberglass shell. Keeping it lightweight.

what is bead board?

Thank you HMS Beagle. Your thoughts on removing that section means cutting the headliner fabric to remove the panel for access and gain a full spread of glue to both surfaces, is best. Esp. since bead board would not hold well with only spots of glue, would tend to break away versus fully spread glue.

I suppose one could apply a length of 2 inch wide hemmed matching headliner fabric to the cut seam. Sort of like trim hot glued to cover the seam of the headliner

The bead board is a structural element, especially in the roof of a NL or Bigfoot. The structure is made up of the outside fiberglass skin, the core of bead board, and the inner paneling, forming a composite sandwich panel. When one of them or the glue bond fails, the individual pieces are quite flexible.

It might be possible to inject an adhesive through the fabric and panelling, but since both sides are covered in the contact cement they use, the new adhesive may not adhere very well to either side, sticking only to the failing contact cement. You likely have nothing to lose by trying it. The alternative is to pull the interior paneling down, clean up the surfaces, and re-glue.

It is a shame that BF and NL do not use a proper structural foam rather than bead board. We always hear about how these are"built like a cored boat" but in fact no cored boat would use bead board as a structural material. My first Bigfoot had extruded polystyrene core, much more suitable than bead board (expanded polystyrene) but still well short of a boat structural core which is typically PVC or SAN material and much stronger both in shear and bond strength. Bead board you can easily crumble in your hand. The issue for them is too much cost I guess.