Brian Lane
Analyst · KeyBanc Capital Markets
Okay, thanks, Bill, and congratulations on bringing Dyna Ten into the fold. Let me start with backlog and activity in various sectors and markets.
Please turn to Slide 5, and start with backlog. Backlog at the end of the first quarter was $612 million, an increase of $9 million compared to the fourth quarter of 2013. This increase is largely due to our existing operations in Central Texas. This backlog number does not include our new acquisition. Pricing, while relatively stable, is still challenging overall. At this point, although underlying activity levels are solid, we do not see an increase in bookings that would support meaningful revenue increase this year.
Please turn to Slide 6 for a look at our end-user sectors. Our industrial and commercial sectors comprised 62% of our revenues for the first quarter of 2014 and 50% of our current backlog. The largest sector is manufacturing, representing just over 1/4 of our first quarter revenue and includes projects such as industrial plants, food production facilities, and data centers. Overall, we continue to win our fair share of small to midsized projects. However, we are still not seeing the larger projects in our backlog.
If you turn to Slide 7, you can see our current revenue mix. Pure service, which is maintenance and repair, was strong at 18% of revenue for the first quarter of 2014 and service, repair and retrofit again exceeded 50% of revenue. For the quarter, our service businesses provided solid returns and our maintenance base has increased by approximately 3% since year-end after a very strong 12% increase in 2013. Overall, we are experiencing stability and we expect to see gradually improving conditions in most of our markets. We have invested in our business throughout the recession, including our recent and unprecedented investment in our service business through training, investing in systems and growing our service workforce and leadership. These investments are significant for Comfort Systems, and we believe that they will benefit us for many years to come. However, they have led to higher SG&A in 2014.
Although our first quarter 2014 earnings and revenues were below the same quarter of last year, we do not believe that these results indicate a trend. We continue to believe that the overall profitability for 2014 will be similar to 2013. We are beginning to experience gradually improving business conditions in many of our markets, and we are optimistic that these trends will lead to improved results in 2015 and beyond.
We are very excited to welcome our new Dallas team members to Comfort Systems USA, and we are confident that this and our many investments over the last few years in people, processes and acquisitions have positioned us for success in 2015 and beyond.
Finally, I would like to welcome our approximately 450 new team members in Dallas and Amarillo. And I thank all of our 6700 ongoing team members for their efforts. I will now turn it back over to Dave for questions. Thank you.