Builders are allowed to build without sufficient systems going in to deal with traffic - or community designs to reduce traffic. If incentives and requirements were matched that allowed builders to install the most efficient lighting and appliances, it would reduce both the monthly costs to power the home and the need to build expensive new plants or burn excessive amounts of polluting fuels. Improvements to building standards may indeed increase costs to new buyers, but can significantly reduce costs and impacts to both the owner and the taxpayer in the long term. Builders are required to install water-saving toilets in both new units and in old ones at the time of sale. This successful program has saved millions for both individuals and ratepayers who don't have to finance additional infrastructure because we used incentives to support smart, prevention-oriented design.
High costs are a factor in any project.
You can design nifty lower-priced homes. Siting them can be pure torture. We must discover the ways to provide housing for the middle and lower ends of the market. When the markets fail, people still need shelter. All the current indicators are showing that we need to increase those standards in the face of runaway growth.