Today I ordered an estimate for soil and environmental testing for the lots from Ambric Tech Corp. Ambric is an engineering firm recommended to me by Brian at Interface Studios. The testing basically consists of drilling a few holes at least 10′ deep in each lot to determine the content and quality of the soil. They will test for contamination or tanks as well as the ability of the soil to support our slab on grade foundation.
Many times in these vacant Philly lots, there was an old home or shop that was torn down in the past. Often these homes were simply collapsed into their foundations and covered over with a thin layer of dirt. This is not good for building a new home on as the ground will settle under pressure from the new structure. There is a good chance that even though we are not building a basement, we will still have to excavate down a few feet and replace the poor soil with new fill that will support our new homes. This is less costly than building a full basement but certainly adds an irritating expense to the construction budget. Also, the soil testing alone will add a couple thousand to our soft cost budget for each home.
I did a quick search on soil testing in Philadelphia and found a good two-pager on the subject written by Habitat for Humanity while doing a green project in the city last year. This document gives a brief overview of soil testing in Philadelphia. It also explains the next steps of getting a survey, submitting plans to zoning and finally getting building permits. Habitat estimates that their pre-construction phase will take 5 years and roughly $15K per home before they even break ground! Welcome to development in Philadelphia. A model for efficiency it is not.
Some more Habitat links below including the pdf version of the document. If you’re in the area I encourage you to check out their annual green building conference. I got a lot of great info from this last year and was able to see some of the top experts on green building in the area speak. This is also where I met Brian Phillips and ISA for the first time.
Habitat 4 Humanity Green Affordable Project Photos
Habitat 2nd Annual Green Building Conference