In a trading update to the stock exchange, the firm described conditions in the housing market as still "extremely difficult".
It completed just 964 new homes for the six months to the end of 2008, compared with 1,174 for the same period a year prior.
The company said the average selling price of its homes was now £171,000 compared with £203,000 a year ago.
The company said: "The housing market remains extremely difficult and we have made significant further reductions in our cost base to align our operational structure to the current market.
"The measures include the successful introduction of a four-day working week across our housebuilding businesses to reduce cost while enabling us to preserve our geographical coverage."
It noted, however, that its activity in the affordable housing sector had "continued to prove its worth".
The board said: "Although overall activity in this market remains muted, in the six months to 31 December we drew down total revenues of £11.6 million under the National Affordable Housing Programme and were awarded further grant allocations for 132 plots."
Galliford Try said it hoped its focus on public sector work would mitigate the effects of the deteriorating economy.
Its contracting order book at the end of last year was £1.7 billion – of which 91 per cent is for the public and regulated sectors.
The company added: "Since announcing our interim management statement in November 2008 the Group has traded in line with our expectations.
"Cash generation in our contracting business remains excellent and we are making progress in reducing the capital in housebuilding.
"The board continues to anticipate that, as announced in the interim management statement last November, a write down of the carrying value of land in the Group's balance sheet of the order of £50 million will be accounted for in the half year results."
It said it would remain focused on tight cash control, the implementation of stringent cost reduction measures and the efficient management of its supply chain.
Galliford Try is expected to announced its interim results for the six months to 31 December in mid-February.
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