This design has a classy look and I think the font is a large part of that, but the "B" is a little slumpy, maybe see what it looks like with another font.
I am liking your designs, I think 15 is still the top, followed by 62 and 60. I like the grey smoke stack on 56, but it almost makes the upper left corner seem soft. My favorite topography for the text is probably 15. Try 62 with the same text as 15.
I really like the logo of 64, but the feedback that I am getting is that I may give off the perception that the only type of construction that I do is residential, can you play with it a little to remove the roof and window and maybe make it a little more universal with residential and commercial construction? One idea would be to incorporate steel I-beams in the letters.
Thanks for all of your entries I am going to be proud to use your logo to represent my company, #64 was my first choice, but I would also like to use #63 and 96 since the design is interchangeable, can I get copies of those files as well.