In current stable patch it takes around 300 m4 shots to destroy wooden frame and wall. This is down from 510 before the recent changes to the weapon damages. If weapon damages are increased then so should health on player made structures be increased. Right now raiding a base is approximately 42% easier than before and raiding in dayz is already fairly easy.
Furthermore, for the last 3 major patches, grenades have been doing equal damage to both wooden and metal walls/gates. It takes 5 grenades to destroy the top part of the wall and the following 2 finish off the bottom part. (Tested this numerous times, changed the distance of the grenade from wall, tested 1 grenade at a time and all of them at once, always the same). It should be 6 grenades to destroy an ENTIRE wooden wall/gate and 7 grenades to destroy ENTIRE metalwall/gate. This is how it was intended and worked before 1.09 update. I was foolish to think someone would mention this to you guys, so here i am finally using the feedback tracker.
I would like to bring attention to the picture i linked below. This is the graph that everyone refers to and i think this is exactly how it should be. Since 1.09 and as of right now, nothing on that picture is correct. This is a system you guys once implemented and i think this was perfect. In short, all my suggestion/feedback is to get back to the system/values you once implemented. I listed this as a "Major" severity since a basebuilding/raiding is something a lot of people care about.