What do you mean one hour later?
Snorting is all you need there is no need to play around with IV heroin if you can avoid it cause snorting heroin salts is a very efficient way of doing it and hits you hard way harder than smoking it because you can only hold so much smoke in your lungs and you can snort a lot of powder up the nose at once. Smoking is always the fastest to come on its even faster than IVing believe it or not cause it goes straight to the brain cause the vessels in the lungs go directly to the BBB but smoking wont last very long at all 1 hour later you can be in withdrawal after smoking some. I used to do both snort a line then smoke a couple tokes to get the instant high from smoking in seconds then a few minutes later the one I snorted comes on hits me hard and lasts way longer then smoking does. IV hits quicker than snorting not quite as fast as smoking but has the most intense rush although snorting does last a bit longer then IVing so its up to you to weigh the benefits and negatives of each Route of administration. All I will say is snorting HCL form heroin is not wasteful at all its bioavailability is quote high.