Yo Summoners my username is CodaJebac and i'm usually playing for fun, so the builds on this site will be most unusuall and fun. All of these builds will work if you fullfill your role, and in this case, it's a pushing one.

You all probably know Heimerdinger's spells but if you don't, all you need to know about them is that his W sends 3 rockets, his Q places turrets, his E stuns/blinds and his ulti gives your turret's mega boost and it speeds up cast time of your e spell. Now the role of the Heimerdinger is

PUSHER

, so to rightly fullfill his role is to PUSH. So since you are pushing your lanes all the time , probably near teammates, it is really handy to buy aoe health/mana regen and similar items that will make your team able to stay in the lane / push for much longer time.
And the last and the most important thing is

BUY WARDS !!

. Always, and i do mean ALWAYS buy wards when you wan't to push, because if you don't you are 100% gonna die since 3 random guys are just gonna jump out of unwarded jungle and kill you.