Yesterday we made the decision to go forward with seeking LEED for Homes Silver rating on both homes in the 100k house project. If you remember in this previous post we were still grappling with this decision due to its uncertain impact on our tight $100K construction budget.
What solidified this decision was an informal meeting I had with Sam Klein of MaGrann Associates to review our design and determine if there was anything major that would add cost to our design if we decided to go for a LEED certification on this project. MaGrann is one of the local LEED for Homes Providers that serves the New Jersey and Eastern PA regions. Sam is very active in the local green events and groups and we seem to cross paths every few weeks at various events and meetings. ISA is also big fans of Magrann and we decided a long time ago to go with them for any LEED or Energy Star rating that we might go after on this and future projects.
The bottom line from the meeting was that Sam did not see anything major in our design that would need to change for us to achieve a LEED rating. Sam reiterated our analysis that if we focussed on the tightness and insulation of the building envelope and generally sought an Energy Star Certified home that we should easily meet LEED certification due to our urban location and infill site. These are all things we have been planning to do from the beginning and are reflected in our design. The simple facades of the home with minimal edges jutting in or out and our effort to minimize the number and area of the windows both for budget and passive cooling also help us a great deal in terms of the LEED criteria.
The main thing that Sam recommended adding to our design specs was an HRV (Heat Recovery Ventilator) unit to economically improve the indoor air quality and pick up some easy LEED points. This had been in the back of my mind but has not made it into our specs yet. We can get a basic unit for $400 that requires minimal ducting and should not add any more than $1,000 to our budget for a nice and healthy home. This is well worth it in my opinion given the fact that the home will be sealed very tight and not exchange natural air at nearly the rate of the average home built in America.
Again, for the purpose of the case study, the cost of the certification and consulting from MaGrann will be kept separate from the $100K construction budget. I view this as a soft cost for the developer, not a hard construction line item.
Prior to our meeting I gave the LEED issue a bit more thought and was leaning towards taking this extra soft cost due to the overall benefit it would have to the project as well as the weight that it would add to our case study. I read articles and case studies every week that state how a LEED certification will cost you 5% – 10% more in hard construction costs. If we are successful in meeting our budget goals then we will have built a LEED home for 20+% LESS than the average home built in the area. Most average homes in Philly are built for abou $120 – $130 psf and we have been quoting $100 psf all along and could reach as low as $85 psf if we reach our $100K goal with a 1,200 square foot home.
Independent of the case study impact, the LEED certification will also offer a lot of valuable consulting on green building from MaGrann including an energy model analysis on our design. The will also conduct multiple tests during and after construction to lend a QC element to the project. This is key as some of the construction materials and methods will be brand new to some of the workers on the project.