Carillion shares jumped 4% to 135.5p while Alfred McAlpine stocks were up 11.5p to 244.5p, as construction continued its bright new year.
The jumps followed statements from both predicting that they would hit year-end earnings forecasts for 2000.
The week also saw a significant jumps for housebuilder Berkeley, up 28p to 796p, materials firm RMC, up 30p to 680p, and builders merchant Travis Perkins, which improved 23p to 719p.
Analysts said the construction sector as a whole was benefiting from the decline of technology stocks and stable economic conditions.
Peel Hunt analyst Stephen Rawlinson was bullish about the sector. He said: "It's been a spectacular start to the new year." Rawlinson singled out Carillion for praise, saying it had carried out its plan to move into the support services market quicker than expected.
He said: "A year ago, I would have said that Carillion remained firmly rooted as an old fashioned contractor. My impression has considerably altered in the last few months." Rawlinson predicted that many companies would begin to mix support services with construction over the next five years. This group would include Carillion, Amec, Amey, Tilbury Douglas, Peterhouse and WS Atkins.
Granville Baird analyst Mike Foster backed Rawlinson's positive view of Carillion. He said: "They have improved the quality of their profits. It's quite a good stock and cheap enough at the moment." Carillion's statement came in the same week that John McDonough started as chief executive.
The group is predicted to post pre-tax profit of 41m for the year to 31 December 2000. This is something of a turnaround for the group, which made a pre-tax loss of £9.3m for the half year to 30 June.
Alfred McAlpine predicted another successful year, with the average selling price for its houses up 18% to £133 800. The firms said its construction services arm had also established longer-term relationships with clients.
