How many rows of spikes? I had 6 rows of wood log spikes around my base in an earlier version. Are you using stick spikes or wood log spikes?
Not many, only a couple. I actually don't have a forge yet as have been very unlikely and found multiple copies of every other book, but no forge. In saying that it's my first play so a lot of it is new to me and I was very conservative early before learning the ropes a bit more. In terms of heat, there were a lot of dead zombies after the first night which left many gore blocks on my spikes, is that what attracted them? Because other than that I haven't really done anything to attract heat.
I didn't really fortify it that much as I didn't think I'd be attacked, having not been attacked in my previous 20 nights hiding out in a barn. In 11.3, do feral hordes still come for you every 7 days? Because as I said that didn't happen in my barn hideout. But in saying that, I had triple layer fully reinforced wood frame walls, overhang to prevent spiders getting in and 2 rows of spikes, 1 of wood log spikes and the other of stick spikes.
Also, are spider zombies noticeable in any specific way? I know what they look like after a google, but from distance they would look similar to any other zombie unless you look closely, or is there something distuingishable they do?