Since defenders can use a 3slot construction site, and begone with it, i'd really like to have a 3slot 2h/polearm or whatever, that can easily destroy such things, rather than the 20hits with PS9 and a large war axe.
So :
Wood cleaver
weapon length: 90
weight: 25
difficulty: 15
speed rating: 38
weapon length: 90
thrust damage: 0 pierce
swing damage: 60 cut
slots: 3
Unbalanced
Bonus against Shield
Price :20k gold
Notice that with such speed, it won't be "overpowered" or even used in battles, since it's toooooo slooooowwww. But to destroy doors or construction sites, or ladders, it's the perfect deal. It will greatly slow you down though, and it uses your 2h, so you can't carry a shield with you (all range will target you). Notice that it has a price, and unlike construction sites/ladders, it HAS a repair cost.
We can, maybe, even make it 4slots.
But since construction sites aren't a problem (or so it seems, since they are still here), i reckon adding an anti-construction site will solve the problem.
EDIT :
Better suggestion : make all axes do +60%dmg to construction sites.