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Minimum window size - NOT egress issue, but based on "room size" - is this an IRC requirement?

As long as egress window is present in the bedroom, then the rest can be satisfied with artificial light and mech. ventilation. Easiest way to do whole house mech vent is to have one of the bath exhausts run 24/7 or a specific ratio - to provide the minimum required air volume per unit of time.
That seems that path of least resistance....and I only have one bath exhaust...and it is at the far end of the living quarters, so running it 24/7 will not bring a "noise issue" - I will research what volume/rate will comply with the Mechanical Code mentioned previously in this thread so that I can purchase a fan to meet these requirements.

Ditto for the artificial lighting... I'll put in additional recessed lighting in the ceiling divided across several individual switches so that the lighting is there, but not all come on at the same time (I don't like a lot of light)

Thanks for your suggestion!
 
Ye but

Doesn’t call for “”” Whole House””.

Isn’t that a little different than normal air conditioning system??????
In my opinion exceptions 1 & 2 in R303.1 of the 2018 IRC make it possible to build a dwelling without any windows whatsoever. Again in my opinion, M1505.1 through M1505.4.1 resolve all ventilation issues relating to windows. I think the homeowner has enough info that the AHJ should strongly reconsider their original determination.
 
In my opinion exceptions 1 & 2 in R303.1 of the 2018 IRC make it possible to build a dwelling without any windows whatsoever. Again in my opinion, M1505.1 through M1505.4.1 resolve all ventilation issues relating to windows. I think the homeowner has enough info that the AHJ should strongly reconsider their original determination.
For ventilation you mean...EERO still applies...
 
If 8% is the threshold and the threshold has not been met, what percentage is proposed? That whole house fan idea is a poor idea. You do realize that you will have to undercut the doors and/or provide pass through grills into the other rooms? What about the electrical use for a fan that runs forever?....and the noise?
 
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If 8% is the threshold and the threshold has not been met, what percentage is proposed? That whole house fan idea is a poor idea. You do realize that you will have to undercut the doors and/or provide pass through grills into the other rooms? What about the electrical use for a fan that runs forever?....and the noise?


Someone got the hint!!!

Plus will be pulling Death Valley Air in!!!
 
Someone got the hint!!!

Plus will be pulling Death Valley Air in!!!
There are no doors on either room - just openings in the wall - the "house" is only 925 SF - the two rooms in question are next to each other... electrical will be negligible - I'm calling my HVAC person today
 
There are no doors on either room - just openings in the wall - the "house" is only 925 SF - the two rooms in question are next to each other... electrical will be negligible - I'm calling my HVAC person today

Has the city blessed your alternate plan??
 
As long as egress window is present in the bedroom, then the rest can be satisfied with artificial light and mech. ventilation. Easiest way to do whole house mech vent is to have one of the bath exhausts run 24/7 or a specific ratio - to provide the minimum required air volume per unit of time.
I do not believe it has to run continuously per M1505
 
Has the city blessed your alternate plan??
I have not approached them with it yet... I want to thoroughly review the requirement of the mechanical/artificial lighting so that I can overcome any objections that they may have... I want a checkmate! My metal building won't be erected until the end of October...then the build pertaining to this issue starts, so I have a bit of time. I will certainly post the results....
 
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Whole house ventilation is defined in the commentary:
"an exhaust system, supply system or combination thereof that is designed to mechanically exchange indoor air for outdoor air. The system can either operate continuously or it can be programmed to operate intermittently."

So if an air handler has an outdoor air intake and the whole house is served by this air then you have "whole house ventilation". The IRC mandates the outdoor air based on the size and number of bedrooms. So if a system is being installed in compliance with the code it is permissible to have less than the 8%.
 
Whole house ventilation is defined in the commentary:
"an exhaust system, supply system or combination thereof that is designed to mechanically exchange indoor air for outdoor air. The system can either operate continuously or it can be programmed to operate intermittently."

So if an air handler has an outdoor air intake and the whole house is served by this air then you have "whole house ventilation". The IRC mandates the outdoor air based on the size and number of bedrooms. So if a system is being installed in compliance with the code it is permissible to have less than the 8%.
That's what I thought - there will be a 3 ton unit to service 925 SF
 
3 tons sounds high for 925 SF unless you have a lot of southwest facing glass, or your insulation is way below IECC standards.
 
3 tons sounds high for 925 SF unless you have a lot of southwest facing glass, or your insulation is way below IECC standards.
NO southwest facing glass - insulation in 2 x 6" studs INSIDE a metal building with 6" insulation all the way around - which bodes well for this unit handling the "ventilation issue" and allowing me the exception - speaking with the HVAC contractor in the morning - I have already introduced the idea of the exemption to the building official and asked "do you accept this"? He said that he did... I need to put my numbers on paper for him.
 
Whole house ventilation is defined in the commentary:
"an exhaust system, supply system or combination thereof that is designed to mechanically exchange indoor air for outdoor air. The system can either operate continuously or it can be programmed to operate intermittently."

So if an air handler has an outdoor air intake and the whole house is served by this air then you have "whole house ventilation". The IRC mandates the outdoor air based on the size and number of bedrooms. So if a system is being installed in compliance with the code it is permissible to have less than the 8%.
I agree - reading this page confirms your suspicions - and I am installing a 3 ton HVAC system; now I need to calculate the lights needed to meet the lighting requirement and I'm golden...
 
An oversized HVAC system is never the answer....I think you only get 15-20% oversizing on the cooling side per manual S...40% on heating...
 
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