Keep the building on your background.
Create the orange layer on top of that, then set the blending mode to Normal and adjust the Opacity to taste.
The white-text layer can then go on top of everything, setting its bled to Normal also.
It's absolutely straightforward.
Thanks, but it isn't that simple. When you just put it on normal and play with the opacity you lose the density of the orange in the sky and even the building doesn't look as good.
Change the blending mode to "color".
Also, it looks like they lightened the sky.
If your background image is grayscale then Multiply will produce a uniform hue and saturation (that of the multiplying layer) but with varying brightness. A desaturated appearance in the midtones could be merely perceptual or it could be that your monitor is not correctly calibrated and profiled. I'll assume the former.
Try putting a Curves adjustment layer between the background and orange multiplier, and use it to adjust the contrast. That won't change the hue or saturation but it may produce a more pleasing appearance.