Frequently Asked Questions
About ECHO System for Basements

Question 1
 
What is the ECHO System intended to achieve and how does it compare to a standard heat recovery ventilator (HRV) in terms of energy savings and Indoor Air Quality (IAQ) achievements?
 
Answer

ECHO is appropriate for all basements, not just for those with problems. It effectively forms the basis for high quality basement finishing.

ECHO reduces energy costs, creates more thermally comfortable living space with better indoor air quality and effectively manages the risk of water damage better than any other system.

From an energy view point, ECHO saves the homeowner between 1/3 to of the typical house energy bill, by providing that much more high quality living space, which would have to be heated anyway. This basement space in most homes is low quality, heated but rarely used other than for storage etc. Often there is mold growth present that pollutes the rest of the house. If the owner desires more high quality living space, he would otherwise have to build an addition which would then add twice the energy cost as originally consumed by the basement alone. It is twice because the new addition must also have a basement. Installing a crawl space often worsens air quality in comparison to a basement. Using slab on grade construction requires a winter slab heating system which is energy costly.

The high integrity of ECHO insulated walls prevent convection currents from reducing the R Value of the foundation wall insulation. Typical foundation wall insulation systems allow air leakage at the top (at the joists and floor above), as well as at the bottom (nearest the slab). This leakage allows the cold air between the insulation and the above grade portion of the foundation to fall to the floor and pass under the insulation and then leak into the house living space. Meanwhile, warm house air enters at the top of the wall at leaks and the cycle begins and continues all winter long.

ECHO recovers some 10 degrees F of heat from the ECHO exhaust air, times the exhaust rate (10 to 85 CFM or more if desired), year around.

ECHO reduces the number and concentration of many typical indoor air contaminants. For example, it eliminates soil gases such as from microbial VOCs, radon, methylene chloride, and sewer gas, all of which are normally found in homes. It eliminates basement construction and finishing material VOCs produced by damp building materials such as by concrete and wood. It eliminates gases and spores from mold growth on poly, wood studs, drywall and carpets. These significant reductions enable lower house ventilation rates to achieve better IAQ than is possible with a standard HRV.

The ECHO System provides owners with whole house ventilation that, unlike HRV's which must be turned off in summer weather to avoid mold growth problems, can be used year round to ventilate the house. In our experience, ECHO house ventilation is more likely to be used than standard HRV ventilation, as ECHO is virtually maintenance free, while HRV's are often a mystery to homeowners, perhaps not even knowing if the device is working.

Exhaust ventilation is cleaner than standard HRV ventilation because the incoming air is filtered through the above ground portion of the house envelope. This filtering yields lower RSP (respirable suspended particulate), concentrations than in mechanically ventilated houses or houses with open windows. RSP values can be 5 to 10 times lower in homes with ECHO Systems than in conventional homes, depending upon outdoor RSP concentrations.

 

Question 2
 
The house is on high ground relative to the neighbors, and the basement is very dry. The basement will be finished as a spare Family Room, so comfort is the main priority. Do I need an ECHO System?
 
Answer

An ECHO System solves not only basement moisture problems. It provides a healthier, more comfortable indoor environment and it protects high quality basement finishing against leakage and flooding. If the home is a long term 'keeper', whatever is done should be done right the first time. Even if it is not, investment in the ECHO System technology can pay off. Recently, installation of an ECHO System in one home enabled its owners to sell this home in a few weeks during a market where months was the norm.

In summary, the ECHO System:

  • Prevents basement mold problems.
  • Improves basement thermal comfort.
  • Enables basement finishing with hardwood flooring.
  • Ventilates the house.
  • Reduces finished basement flood damage.
  • Prevents soil gas entry (e.g., cancer causing radon gas, sewer odours)

 

Question 3
 
Is ECHO the only sustainable system that will provide a warm floor?
 
Answer

No. An electrically heated concrete slab will provide a warm basement floor, but at an energy cost and without protecting finishing material against basement water leakage and sewer back ups.

With respect to energy costs, an ECHO sub floor saves about 30% of the energy required to heat a typical basement. ECHO perimeter walls also save on energy costs. These walls have a higher thermal resistance than standard walls with the same nominal R-value due to lower convection current losses. In a standard insulation system, convective losses are high due to the typically poor vapor barrier sealing at the top and bottom of the wall.

 

Question 4
 
What is the extra cost of ECHO?
 
Answer

The extra cost of ECHO over standard perimeter stud walls and carpet on concrete is:

  • $2,000 to $2,500 for the ECHO mechanical system and ECHO wall and subfloor sealing measures.
  • $5-$6/sq. ft. for the ECHO sub floor.

 

Question 5
 
Should I get an HRV if I get an ECHO System?
 
Answer

Adding an HRV is not necessary when you get an ECHO System. However, if you already have an HRV, ECHO exhaust can be passed though it for additional energy savings.

ECHO ventilation provides house ventilation at rates between 10 and 85 CFM. It is an exhaust ventilation system, drawing air into the house through the above-ground envelope and exhausting the same amount of air from the house via the below-ground ECHO Envelope. In contrast, heat recovery ventilation both exhausts air from and pumps air into the house. This ventilation dilutes house air contaminants but does not prevent basement envelope contamination accumulation and entry.

ECHO ventilation eliminates basement contaminants at source, and dilutes house air contaminants. Typically, an ECHO System ventilation rate can be adjusted between the amount required to just depressurize the basement envelope (typically 10-20 CFM) and 85-CFM. The high setting is designed to remove any moisture wicking through the foundation concrete and to meet building code ventilation requirements.

ECHO ventilation reduces above-ground and below-ground envelope moisture accumulation. Conversely, HRV ventilation causes basement envelope moisture accumulation in summer weather. HRV flow imbalances can cause above-ground envelope moisture problems in winter weather.

ECHO ventilation filters ambient air respirable suspended particulate matter (RSP) and mold propagules better than HRV filters.

ECHO ventilation reduces both above and below-ground envelope radiant energy losses. It also reduces exfiltration convective energy losses. The below-ground losses are reduced year round through heat exchange between the exhaust air and the foundation, which is typically 3-7 degrees Celsius below room air temperatures. HRV ventilation, which can be added to ECHO ventilation, will reduce exhaust air heat losses further by recovering about 50 percent of the heat in the incoming air. However, as noted above, use of an HRV will increase indoor air particulate counts and possibly mold exposures.

 

Question 6
 
Will ECHO interfere with a wood-burning fireplace?
 
Answer

All exhaust devices:

  • bathroom fans (50-110 CFM),
  • clothes dryer (150 CFM),
  • kitchen exhaust fan (100-250 CFM),
  • furnace fans (upstairs-basement pressure imbalances of 0 to 100 CFM or more),
  • HRV (flow imbalances of 0 and to 100 CFM or more),
  • the ECHO System (10-85 CFM)
  • an open upstairs window (100's of CFM)
can potentially interfere with the full exhausting of combustion fumes from a wood-burning appliance and cause carbon monoxide spillage indoors, depending upon house tightness and wind conditions. The most likely time for such spillage is at the end of the fire during smoldering. Never go to sleep with a wood appliance burning unless there is a carbon monoxide warning device installed between you and the fire. If the appliance does not have its own outside air supply duct, while it is burning open a window on the same or a lower floor.

The ECHO System pressure monitor can be used by the homeowner to measure indoor/outdoor pressure difference under the various possible house and fan operating conditions to clarify whether or not a spillage problem is likely to occur for this or any other fuel burning appliance. The protocol is described in the ECHO System Homeowner's Information Document.