Is this normal for a Delta roof?

[Ox262]

I'm considering a 2026 Delta 262RB. I've done two detailed walkthroughs and everything looks and operates normally. However, when I went up on the roof I found the Dicor looked pocked and it seems to have black particles stuck to it. Almost looks like bugs stuck in the Dicor. Can anyone comment on the caulking? And secondly, I can see what looks like ridges in the roof material, side to side, spaced evenly. Looks like seams in the roof substrate? Any input is welcomed as we're considering purchasing this unit. Thank you.

 

[Long Islander]

We had the same problem with our Delta 292RL. I called customer support and sent them picks. They agreed that there was an issue and agreed to fix it. They told me that they got a bad batch of Alpha System Lap sealant. They said that I can go back to the dealer or they'd mail me new sealant and I could repair it myself. Since we live 5 hours away from the dealer, I did the repair my self. So, I went up on the roof and scrapped off the bad sealant. For some reason the sealant never really set up properly and it came off easily. I scrapped off ALL of the bad sealant and reapplied the new sealant that they sent me. All good...Right??? Wrong! After a few weeks I noticed that the new lap sealant was just as bad as the old sealant. I noticed leaves, dirt, twigs was sticking it in and in short order the new sealant looked just as bad as the original lap sealant used! So I called back Alliance customer support, sent more picks and this time I even sent videos. Again they agreed that there was an issue and offered to send more Alpha Systems lap sealant. Apparently their vendor sent me out more of the same bad batch. I refused to use any more Alpha Systems lap sealant, so Alliance customer service said I that could buy whatever type I wanted and they'd reimburse me. So I ordered Dicor Lap sealant from Amazon. I them scrapped all the sealant off for a second time and this time I used Dicor lap sealant. The roof now looks just fine. It was a pain in the neck, but Alliance customer service was great to work with.

I posted a few pics of the original bad sealant below. Keep in mind that the trailer was less than 6 month old.

 

[Ox262]

Interesting. I looked at 4 Delta trailers, two were built in May 2025 (including the one I want) and both had the lap sealant that looked 5 years old. The two other Deltas, one built in July and one built in August, and both of those has lap sealant that was white and looked great.

Also, I think the side to side ridges are the glue? holding the membrane down. Every Delta I looked at had the same roof ridges evenly spaced.

What is the build date of your Delta?

 

[Long Islander]

Ours was built 08/20/24.