Cuyahoga County Urban Mold & Moisture Program
Supported by a grant from the HUD Healthy Homes Office

Project Partners: Case Western Reserve University, Department of Pediatrics, Rainbow Babies and Children's Hospital; Cuyahoga County Board of Health; Cuyahoga County Department of Development; Cleveland Housing Network; Environmental Health Watch

Reduction in Asthma Morbidity in Children as a Result of Home Remediation Aimed at Moisture Sources, Environmental Health Perspectives (pdf - 7 pgs.)
Interventions Full report (pdf - 8 pgs.)
View Intervention Power Point Presentation (pdf - 33 pgs.)
Print Invervention Power Point Handouts (pdf - 6 pgs.)

Overview and Summary of Clinical Results
The Cuyahoga County Urban Mold & Moisture Program (UMMP) explored the relationship between mold, moisture, asthma triggers and the respiratory health of children living in inner city neighborhoods throughout Greater Cleveland. Simultaneous clinical /environmental assessments and sampling occurred over a twelve month period. A total of 104 homes received environmental interventions focused on the reduction of water infiltration, removal of water damaged building materials, HVAC alterations, lead hazard control, and environmental cleaning.

Clinical samples (blood, urine and nasal washing) were collected from children and the primary caregiver living in the home. These samples were analyzed for a variety of allergens. Environmental dust samples were analyzed for dust mite, cockroach, rodent urinary protein , endotoxin and fungi.

Moderately severe asthmatic children had a significant decrease in symptom score (p<0.006) and symptom days (p<0.003) following remediation while these parameters in parallel control children in homes not receiving the interventions did not significantly change. During the period from 6-months post-randomization to the end of the study, which was primarily post-remediation, asthmatics receiving home interventions had a lower rate of exacerbations compared to control asthmatics (1/29 vs. 11/33, respectively, p=.003). Other children, not specifically enrolled because of asthma, had a significant decrease in nine out of 14 upper and lower respiratory symptoms following the home interventions.

Mold and Moisture Control Interventions
General Strategy

• Remove moisture damaged material.
• Remove mold exposure pathways.
• Clean mold from hard surfaces.
• Stop rain water intrusion.
• Exhaust water vapor.
• Repair plumbing leaks.

Key Specifications Developed

• Duct cold air return directly to the furnace (repair the "Cleveland drop") .
• Flash the soil to the house.
• Treat the porch like a roof.
• Eliminate sub-slab duct and heating systems.
• Disconnect and redirect downspouts.
• Reduce moisture in crawlspaces.

Duct cold air return directly to the furnace (repair the “ Cleveland drop”)
If the forced air heating system had cold air return ducts that were not directly connected to the cold air return vent on the furnace (the “Cleveland drop”), this was corrected. However, sometimes, when the Cleveland Drop is corrected, contractors use the space between floor joists to carry the air toward the furnace. This is called “panning” the joists, affixing sheet metal across two joists to create an enclosed air space. There are two problems with doing this - 1) the joist cavity itself can be very dirty and 2) if there is excess moisture in the house, it can be pulled into the joist cavity where it can contribute to mold growth. Similar practices should be discouraged in any forced-air furnace installations.

Flash the soil to the house
Bill Rose, a research architect, at the University of Illinois , has coined the term “flashing the soil to the house” for a low cost system he developed that greatly reduces surface water from entering foundations of residential structures (see Fine Homebuilding Magazine, Aug-Sept, l998 issue, “Ideas for Wet Basements”). The method involves excavating a trench along a foundation wall that is permitting water to enter from the exterior. The trench should be about 12-16” deep and 2-3’ wide and sloped away from the foundation. EPDM, a rubber roofing material, is placed against the foundation wall and along the trench. It is then fastened to the side of building using a metal strip that is secured to the mortar joints of the wall with Tapcon screws.

Treat a porch floor like a roof
In Cleveland, we have many homes with porches that are over the basement. Water can leak through the porch floor into the basement, causing moisture problems, including mold. First, an underlayment material was installed (much like roof sheathing), then felt paper was installed (again, like on a roof surface), then new flooring would be installed over it. It is quite expensive. Because of our limited funds, for this project we installed two layers of 6 mil plastic on the old flooring surface and sealed it around its perimeter. We then installed indoor/ outdoor carpet over the plastic surface. The result is a sealed surface that will not permit water to enter the flooring and provides an attractive, low cost finish. Another benefit is sealing in the lead paint that is inevitably on old porch floors of this vintage. A possible downside, which needs to be tested, is whether using the indoor-outdoor carpeting creates a sink for lead dust that people track onto the porch from soils around the house and from the street. Is this a lead exposure hazard for children or does the carpet act as a lead dust trap?

Eliminate sub-slab ductwork and heating systems
Houses with a slab foundation often have duct work for their heating system under the slab and it can develop leaks over time.  When this occurs, the moisture can be vaporized when the heat is on sending this moisture all over the house and creating serious mold problems . There is no remedy for this condition using the existing system. The solution we have found to be most effective includes sealing off the old ductwork and the space under the furnace with cement, installing an updraft furnace and installing new ductwork in soffits created along the center wall in the houses. This ends the moisture problem, thus the mold problem, and the only downside is slightly less comfortable floors because there is no longer any heat traveling through them. While no study has been done of energy savings to date, residents report lower heat bills because there is less heat lost to a cold sub-floor and they experience greater overall comfort in their living spaces.

Disconnect and redirect downspouts
Some communities are now permitting downspout disconnection from the storm drains in the ground and this dramatically reduces water entry in many basements. However, it is critical that the downspout leads be placed at the bottom of each disconnected downspout and these leads should be at least 5’ long to be sure water is carried away from the foundation of the host structure and any neighbor’s foundation. We have also found that resloping gutters so they carry water in a direction that carries the water closer to the street before it drops can eliminate the need for much of the underground storm system.

Remove wood shelving in basements
Removing this old wood material and replacing it with plastic shelving to keep paper, cardboard, clothing and other such materials off the damp floors and away from damp walls can significantly reduce mold growth in many of these homes.

Reduce moisture levels in crawlspaces
There are literally hundreds of homes in Cleveland with crawlspaces that are usually just dirt floored and are vented deliberately and/or have plenty of air leakage that allegedly vents the moisture levels emerging from the soils. We have been learning that the best way to treat these crawlspaces is to first solve any moisture problems (standing water especially), then cover the soils with heavy plastic sheeting that is carried up along the foundation walls to at least above grade level on the exterior; then we insulate the perimeter walls, eliminate the vents into the crawlspace and open the crawlspace to the warm portion of the basement. Before this is done, all debris which is lying in the crawlspace is removed and this often includes all manner of cellulose products that have mold growing on them.

In this project, we were only able to install plastic sheeting after removing debris, which reduces the moisture entry into the space. Here is a potential interface between healthy housing and weatherization work. An additional health problem that we could not address with this program is rat control where rats come into the houses by burrowing under the foundation walls and into the crawlspaces. When funds are available, it is common practice to install what we refer to as a “rat slab” of concrete about 2” thick to reduce this problem. The concrete is poured on top of the plastic to reduce moisture wicking through the concrete and into the crawlspace.

Reduction in Asthma Morbidity in Children as a Result of Home Remediation Aimed at Moisture Sources, Environmental Health Perspectives (pdf - 38 pgs.)
Interventions Full report (pdf - 8 pgs.)
View Interventions Power Point Presentation

Draft 1/4/05

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