Chicken

Sure they could, they'd just have to rebuild wood a lot. And actually at this point (only two generations isn't that long) they should have had a good amount of metal and metalworking skills they could employ into theoretically lightweight roofing to reduce the needed build time of their floating village. But there is the consideration of crops on land. The best solution there would likely be "vaults" in the form of caves etc altered to keep out moisture and animals, kept stocked with both viable seeds and food at all times, and significant crop lands with metal or stone shelters strategically placed and equipped with flamethrowers throughout the croplands. Hey I solved Pern just by being annoyed by "well they couldn't live on water!!" These colonists were really bad at their job.