Whole-house Ventilation

[fatboy]

I've been told that Section M1507 of the 2012 IRC requires whole-house mechanical ventilation. I'm not seeing M1507 as a requiring whole-house ventilation, but as the rules for if it is. Am I missing something?

 

[Codegeek]

I read it the same way you do FB, if they provide it, then the requirements are provided in M1507. Maybe someone else can enlighten us if we're not correct.

 

[Codegeek]

FB, I think I may have found the requirement...do you have access to the 2012 IECC? If so, look in Section R403.5. It has the mandatory requirements for ventilation, which include the whole house ventilation. According to the book I received at an IECC class, the implied reference here is to M1507 saying that the building has to be provided with ventilation that meets M1507 OR with other approved means of ventilation.

Hope that helps.

 

[Gregg Harris]

I've been told that Section M1507 of the 2012 IRC requires whole-house mechanical ventilation. I'm not seeing M1507 as a requiring whole-house ventilation, but as the rules for if it is. Am I missing something?

Have you deciphered it yet. I do not have 2012 I codes yet but from what i can gather it is the standards for mechanical ventilation if the house has less than 5 air changes per hour as tested with a blower door at a pressure of 0.2 inches of water column or 50 pascals then the dwelling unit shall be provided with whole-house ventilation in accordance with section M 1507.3

 

[chris kennedy]

I do not have 2012 I codes yet

The 2012 codes are here.

 

[mjesse]

if the house has less than 5 air changes per hour as tested with a blower door at a pressure of 0.2 inches of water column or 50 pascals then the dwelling unit shall be provided with whole-house ventilation in accordance with section M 1507.3

...and the energy code requires that a dwelling unit shall have not more than 3 air changes per hour in Climate Zones 3 through 8. Thus, whole house ventilation (WHV) for all homes in zones 3-8



mj

 

[Keystone]

Can wole house ventiation be accomplished by placing a heat pump on fan mode?

 

[Gregg Harris]

Yes provided there is an outside motorized damper sized to accomplish the ventilation. But it would be more economical to use either an ERV or an HRV depending on the climate the home is in.

 

[mjesse]

Can wole house ventiation be accomplished by placing a heat pump on fan mode?

You need to be able to bring outside air (make-up air) into the building.

IMHO, the ERV/HRV systems are the intended solution.

mj

 

[Gregg Harris]

The 2012 codes are here.

Thank you Chris, but if I had your money and my time I could purchase a new set that I can print from rather than my manuals. I prefer to use manuals and highlight but when I travel it is much easier to have it digital.

Now with that said who can tell me the best type to purchase? I think I was told IQUEST will allow you to print and high light.

 

[Gregg Harris]

I would agree and the system must have an ECM motor either variable speed or constant torque. The probable with that stipulation is that it does not require the ECM to be operated at the designed and tested static pressure.

If installed on a restrictive duct system the current usage can double and eliminate any savings that could be expected.

 

[zigmark]

This has been around for a while in Washington States' Energy Code. There are 4 options within the WSEC to accomplish whole house ventilation. The condensed versions are as follows. 1) As described above a timered damper is provided on the return side of the furnace and is set to open the damper and run the airhandler a calculated amount of time within a 24 hour period or continuously. 2) A source specific exhaust fan, usually in the laundry area, of a calculated size based upon #bedrooms and sq footage of heated space is provided and set to run 24/7 or shorter spaced intervals such as 3hrs for 4x per day, their are air inlets provided within each habitable (vents in windows or fresh air 80's) room and all interior doors are cut 1/2" above the finished floor. 3) the use of an ERV, HRV or similar unit that has the ability to provide outside air at a calculated rate is filtered and set on a timer to run similar to #2. 4) A supply fan is provided and sized to provide a calculated amount of outdoor air similar to the HRV systems.

Up until the most recent code cycle these requirements were part of a Ventilation and Indoor Air Quality Code. They were originaly part of Washingtons' Energy Code and now are incorperated into the Mechanical Code as ammendments.

ZIG

 

[Keystone]

Yeah Duhh, guess you would need outside air. Brain Fart what else can I say.