Detroit Housing Investment

Harley Stanfield

Detroit Community Building Project

Project Mission

Gut-rehab of two brick buildings circa 1923 in a troubled community. The budget is approximately $400,000 total (for both buildings).

Use the buildings as the beginning of large scale rehabilitation of Detroit housing.

Location

6332 and 6334 E. Warren Avenue

Detroit, Michigan 48207

Longitude and Latitude 42.370617 N, -83.026922

Map view http://tinyurl.com/279tu8j

The two dark roofs at the corner of Warren and Meldrum

Street views http://tinyurl.com/2bzgun4

http://tinyurl.com/2c26myr

Building Information

Each brick exterior building is 33 feet wide (front) by 50 feet deep;

Each building is two (2) stories over a full basement;

Each building has two (2) mirror image apartments on each floor - 4 apartments per building; and,

Each building is equipped with front and back stairwells inside centered between the apartments.

Each building has a slightly sloped, hot mopped roof with about 15 in. to 22 in. from the ceiling to roof.

Each apartment is approximately 710 sq ft with 8' 9” ceiling height.

Each identical (mirror image) apartment has 2 bedrooms, 1 bathroom, kitchen-dining, living room and hall, with 2 entry doors; one to each stairwell.

No combustion equipment will be in the apartments. One gas furnace will be placed in each basement.

Existing Conditions

Each building will be gutted from inside, all lath and plaster stripped, baring all exterior wall framing, exterior/top ceilings and exterior band boards.

The existing brick exterior over platform framed walls is as follows - from the inside:

3.625" studs with ¾" x 8” boards nailed to exterior of studs as sheathing, then 3/4”-1" air space (the old building paper has rotted away), then an exterior, nominal 4”, brick wall from foundation to roof.

There will be wiring, but no plumbing in exterior walls.

Energy Plan

The guiding premise is a targeted 60% to 70% total annual energy reduction for the Detroit buildings compared to similar size units.

We will start by applying an approx. 1” thick, closed-cell urethane foam air-seal (pressure seal) sprayed on the inside of the 3/4” sheathing, the band boards and the underside of the roof sheathing – thereby sealing the entire exterior shell. We will make efforts to seal any and all penetrations, also seal the first floor and then pressure test the system.

We will apply foam to achieve approximately 2-3 ACH50. That equates to about 0.13 ACH to 0.20 ACH at normal pressures, based on previous experience.

After the foam air-seal, the walls will get dense pack cellulose to achieve an approx. R-16 wall and the ceiling will get more foam to achieve an approximate R-28 rating.

All ductwork will be inside the thermal envelope, short, mostly straight and will discharge from the inside part of the rooms, aimed toward the ext walls.

A roughly calculated heat load for a second floor apartment is about 11,500 BTU/hr maximum at the Detroit Edison, -10 degree F design temperature and about 18.5 million BTU/yr with 2 occupants.

More accurate calculations and simulations will likely change these estimates.

The 1^st floor units have a max loss at the design temp of -10 F of 11,700 BTU/hr and 18.8 million BTU/year with two occupants.

All 8 apartments will be blower door tested upon completion and some will be tested during construction. Completed buildings are expected to be sufficiently tight that continuous or cycled ventilation will be required.

Expert Insight

Expert insight from experienced building industry professionals is sought on the following issues:

Windows:

We are planning on using R-5, triple pane windows from Serious Materials or Canadian window manufacturers. We have not yet priced R-7 and R-9 units from Serious Materials, or other. We are open to window suggestions.

HRV:

We are seeking input to determine if it’s best to use an HRV (such as the Fantech VH704, or the VHR 704), or whether using a continuous exhaust fan in the kitchen and bath with trickle make-up air would be satisfactory for our goals.

We are seeking furnace recommendations:

There will be a single, central, natural gas, condensing furnace in the basement of each building, supplying both heat and hot water to each apartment. It will be in the 95% efficiency range and vented horizontally through PVC pipe. We are planning to use an approx. 200,000 BTU furnace linked to a 119 gallon hot water tank and heat exchange. I believe local codes create problems with units that are 120 gallons and larger. Hot water for heat, using a water to air heat exchange located in the in the vent system plenum, will be distributed from a central condensing gas furnace. Domestic hot water will be supplied from the same furnace by way of a water-to-water heat exchanger in the 119 gallon tank.

Automated controls:

We are seeking recommendations for automated temperature and vent control systems appropriate for this 4 unit building?

We are seeking recommendations for an affordable and effective hot water energy meter.

We would like to examine various rental contracts that prescribe incentives to save energy and offer rewards for conservation.

Water Distribution:

We plan to use a PEX system. We welcome comments and other notes regarding installation, durability and insulating measures.

On-demand water recirculating system.

We love Gary Klein's on demand water recirculating system. Has anyone established a price differential vs. non-circulating, small pipe PEX distribution? We will probably not opt for this luxury.

Heating:

When heat is needed it will be supplied from a water-to-air heat exchanger using the same duct system used by the HRV. Pumps will be activated by a programmable thermostat. Ach apartment will be on a separate system.

We are seeking recommendations for effective heat exchangers that do not put much drag on the low-powered circulation fans.