Newb needin help!!again!!

[Apophis]

Ok I can't seem to get it right. First off my house is heated by window ac's so my house is always at diff temps. Btw 64 in mornin to up to 80 in afternoon. I have very little control over this.
Second I have a ten gallon tank with a screen top, 2 hides, water bowl, and branch. I'm using reptibark wood chips for substrate. I am using a ifr heat bulb for now but I have a 10-20 gal uth but no t-stat for now?
Now for my q's.

1- is a ten to small to have a good temp grade? I'm having big trouble I can't get the surface temp on the warm side under a hundred I know I need to get a dimmer for it until I can get a t-stat.
2- do I need to build a lid for this tank instead of using the screen?
3- if I do build a lid for the tank will my uth provide enough heat to the tank or will I need another heatsource for the coolside?
That's all of my q's for now I hope

[snakesRkewl]

my house is heated by window ac's so my house is always at diff temps. Btw 64 in mornin to up to 80 in afternoon. I have very little control over this.

Never use a uth without a t-stat and you answered your own question as to whether a dimmer switch will work, it won't.
If your room temperature goes up and down like that so will your uth, you will need a thermostat.

Truthfully ten gal tanks work "ok" under the best of situations, you might look into getting a t-stat and housing your snake in a tub on heat tape.

[Apophis]

I'm not currently using the uth I'm using the heat lamp. And I was talking about a dimmer for the lamp. I plan on getting a t-stat asap but will the uth keep my tank temps right? Jw I'm very new to all of this. And what is heat tape or flexwire? How hard is it to set up and cost?