Make-Up air ventilation

[Daxin]

Me and a buddy are thinking about setting up a auto repair shop and we were told that the city of Calgary passed a new by-law enforcing new shops to install Make-up air units where there's exhaust fumes inside.

These Make-up air units go for about $40K to install and I was wondering if there was a way around it to have a cheaper type of air ventilation system.

Thanx

[97'Scort]

Gotta pay to play, son.

Or you could rent a shop with one already. Or you could eliminate the problem by not having exhaust fumes inside, IE one of those nifty holes in your garage door with a hose attached to the tailpipe. That's all we ever used.

[Daxin]

This new bylaw came into effect 6 months ago, so I was told by the commercial Realtor. I wish I could drill some holes for the exhaust fumes, but I was told that was not good enough.

[97'Scort]

Then ask the realtor to get you a copy of the bylaw, and see for yourself what system is required. I somehow doubt they want every mom and pop shop to drop trou and take a $40k pounding over some exhaust fumes.

See what's required, what certification the system needs, what volume of air is required to be replaced, and get back to us.

[lint]

this city is retarded. They want homeowners to put in make up air if they put in a range hood that exceeds 180cfm at a minimum cost of $3.5K in addition to the cost of the range hood. I haven't found an island range hood that runs under 600cfm. what the fuck happened to just opening a window?

[ExtraSlow]

Originally posted by lint
this city is retarded. They want homeowners to put in make up air if they put in a range hood that exceeds 180cfm at a minimum cost of $3.5K in addition to the cost of the range hood. I haven't found an island range hood that runs under 600cfm. what the fuck happened to just opening a window?
source?

[nusneak]

It is true, homes and commercial buildings require make up air whenever there is exhaust fans bigger then a certain size.

Some people living in a run of the mill house built in the past few years might notice when they turn on their master bathroom fan, it is interlocked with the furnace/make up air to bring in fresh air.

Edit:
Page 12 here (http://74.125.155.132/search?q=cache:0UpA6MQFjPAJ:www.calgary.ca/docgallery/bu/dba/building/hvac_newsletter.pdf+calgary+make+up+air+required+exhaust+bylaw&cd=3&hl=en&ct=clnk&gl=ca&client=firefox-a) for residential.


A kitchen exhaust fan rated for up to and including 300 cfm
may be installed in a house that is served by a forced air heat-
ing system without any extra consideration for make-up air.
This is based on Section 9.32 of the 1997 Alberta Building
Code that permits a deficit of 160 cfm and the typical fresh
air duct sized for forced air systems.
If the exhaust fan is rated for over 160 cfm, then the fan
must be interlocked with a make-up air source, such as a
forced air furnace with a fresh air duct from the outdoors to
the return air duct. When the rated capacity exceeds 300 cfm,
the make-up air supply must be designed to bring in enough
air and may require pre-heating to maintain mixed air tem-
peratures in the return air system.

[frozenrice]

Originally posted by lint
this city is retarded. They want homeowners to put in make up air if they put in a range hood that exceeds 180cfm at a minimum cost of $3.5K in addition to the cost of the range hood. I haven't found an island range hood that runs under 600cfm. what the fuck happened to just opening a window?

Opening a window makesl sense when it's nice out. Try that in -30C weather. Not likely to happen.
It's an expensive option going with larger capacity hood fans, but on the flip side, I'd rather not die from O2, so I'd be more than glad to pay it if I had to.

FYI, 180-299 cfm should require nothing more than an interlock to your furnace (it's a current sensing relay that turns the furnace fan on to act as the make up air when you turn on your hood fan). The interlock should be in the range of about $4-500. When you're going with anything over 300cfm, you need to preheat the air (for winter conditions). -30C air is not good on the heat exchanger on your furnace - the condensation from the temperature extremes will cause premature/rust. So, now your talking about inline heaters etc, in addition to the relay. Add maybe another $1000 for the heater on top of the $4-500.

$3.5k seems high, but it's likely because you're in the +600cfm range which is in another category. It depends on what method your builder is using for this. Sounds like it might be a secondary furnace for that price.


edit: looks like nuseak found the source

[Maxt]

For a residential, small commercial make up air application, use a mid efficient furnace with stainless exchangers and a maxitrol valve, you can even gang them together to achieve higher cfm volumes. Lennox and tempstar are popular choices, lennox has an mua package.
Its a cheaper way and can work in commercial applications, but the indirect fired units will consume more gas than direct fired of course.
40 K installed buys a pretty large machine and exhaust, it depends on what the size of the shop is.
ashrae recommends no more than 8 hours exposure to a direct fired mua. Most small shops work longer than that.
Welding shops, chemical plants, food manufacturing, sure.. But 2 bay fix it shops, wonder what the kickback ratio is ...

[Daxin]

Thanx guys. I'll inquire roughly how much it would cost to ventilate a 2000 Sq/Ft bay.