[Strawbale] Distributed ventilation

[David Neeley]

Don,

I live in a climate which is fairly brutal in the Summer--quite the
opposite of what many of your readers face in Canada. (I am in Texas).

What is the drawback, if any, to integrating an ERV into the ductwork
for a forced air system?

The house I am designing will be quite small in area, but I am
planning a geothermal heat pump that has a multi-speed fan already. My
thought was to use the ERV to precondition makeup air for the heat
pump, and to use it for ventilation air when the heat pump is not
operating. Other, perhaps, than efficiency issues when the heat pump
is not working, are there difficulties with this plan of which I am
not aware?

Thanks!

David Neeley

On 4/12/07, dfugler at cmhc-schl.gc.ca <dfugler at cmhc-schl.gc.ca> wrote:
> Good morning list,
>
> Rob is right (as usual). If you do not circulate fresh air, some rooms
> will be underventilated and some overventilated.

> ). Furnace fan energy consumption can be lowered either by cycling the
> furnace using a product such as AirCycler or by installing a furnace with
> an ECM or equivalent motor, which uses very little electricity at low
> speed. Most straw bale houses though don't seem to have furnaces anyhow,
> so this may be moot. A ducted HRV, with supply air to the bedrooms and
> exhaust from kitchen and bathrooms, is the most efficient way to
> distribute fresh air in the house. The full ducting, instead of using the
> furnace ducting, can cost you another $500-$1000 at the time of
> construction.