Fumes and new construction

[berntsang]

Hello all,

I have searched and have not seen this my apologize if it’s already been asked and answered.

In my neck of the woods the only way to get some size on a garage is to unfortunately make it an attached. So we’re building a new house so I can get the garage I want 1500+ sqft with 16ft ceilings. However the garage is attached right next to the kitchen and there are several bedrooms above the garage. (6000 sqft house )

That brings me to my question. Is there anything I should be considering to make sure that my garage fumes (welding, fuel, spray cleaner and penetrating oil, roll on epoxy paint, sanding etc) stays contained in my shop and doesn’t bother by family in the rest of the house. The shop will have its own self contained HVAC system and will have a large exhaust fan. But in the very cold months I don’t see myself wanting to run the exhaust fan or leave the garage door open.

As I write this the question seems more and more moronic to ask. I will of course make sure as I’m building it the doors going into the house are sealed tightly. But we all know the smell on some of the things we use in our shops is not something you want your family to deal with.

Thanks all!
Feel free to add anything else I should be considering on new construction attached.

 

[c39er]

Industrial ventilation system just liken in a real shop.
Might cost some money but looks like not a problem in your build.

 

[ericm]

I rented a house with a large add on room in the back that I turned into shop space. The first time I painted a motorcycle in there the fumes were obnoxious in the house. I then set up a cheap "paint booth" using plastic sheeting and gave it a ventilated negative pressure using a fan and ducting. Low cost but it cut about 90% of the smell.

Outside type sealed doors, and maybe a mudroom between the garage and shop so there's two doors, would help quite a bit. The house I just moved from had that and no smells got into the house.

 

[Vwpower]

Maybe have like two doors with a small space between them like a commercial entrance. Open and close one door then open the other.

 

[Youngandfree]

Build it as a detached and add a breezeway to attach it.

 

[PWC Repair]

I've watched A LOT of home renovating/flipping type shows and inspection videos on Youtube while researching things as I build my son's house. I can tell you for sure that MOST garages are NOT sealed like they need to be. You will need to babysit the boys to make sure it gets sealed and caulked EVERYWHERE. I would also plan for a small.......maybe 12-16 inch louvered power vent in one end and a window somewhere ACROSS the garage. You could turn it on and crack a window for a low cfm steady cross draw while you're working. Nothing huge to **** out all your heat or a/c,.......just enough to steadily evacuate fumes.

 

[manwithtools]

You will need to babysit the boys to make sure it gets sealed and caulked EVERYWHERE.

Simpler solution to being the caulking watch dog - spray foam. It REALLY cuts down on air infiltration.

 

[wssix99]

I have the same setup. Closed cell spray foam seals the garage from the rest of the house. We use a HRV for ventilation ,which keeps the heat in when the fan runs.

 

[Red 17]

Most of it should be "good" with a quality drywall job and fire sealant at any penetrations. Or just eliminate penetrations on that wall. No switches or outlets etc.

The door will be the only way in for nasty stuff, so double doors or industrial strength seals. The mud room idea is a very good one.

 

[Nobody-named-Olli]

If you can spend the $$$$ this is your solution for welding fumes. https://www.kemper.eu/en/products

Kind regards,
Olli

 

[zimman]

Industrial ventilation system just liken in a real shop.
Might cost some money but looks like not a problem in your build.

A 10,000 cfm fan on a 6,000 sqft house is chump change LOL
Zim

 

[BillK]

I think a lot of the suggestions are overkill but you never know. If the garage is finished drywall and you have the required fireproof door going into the house I doubt that you can do much better. I would want an exhaust fan up as high on the wall as possible.

 

[Bottlecapdigger]

The building code has required rules for attached garages, just follow the laws. BCD

 

[Bert_]

That's one thing I've never liked about the shouse. I think a lot of them don't get any real work done inside so it doesn't become an issue.

If I was building it there would be a breezeway, not connected to either HVAC system, between the buildings.

 

[JohnX14]

I think a lot of the suggestions are overkill but you never know. If the garage is finished drywall and you have the required fireproof door going into the house I doubt that you can do much better. I would want an exhaust fan up as high on the wall as possible.

This. You will need the required fire separation of 5/8" between garage and living space. And the required door. You can do a separate garage exhaust. You can increase the fire separation, you can omit the door from the attached garage to the house. But if the garage fumes are the concern, then exhaust them....

 

[Overboost44]

Maybe an air curtain between the garage and the house door and then seal everything as mentioned above.

 

[berntsang]

That's one thing I've never liked about the shouse. I think a lot of them don't get any real work done inside so it doesn't become an issue.

If I was building it there would be a breezeway, not connected to either HVAC system, between the buildings.

Yup, unfortunately with set back and all the zoning things where I am I don’t have the space to do a breezeway. But it will have its own standalone HVAC system.

 

[Bert_]

Yup, unfortunately with set back and all the zoning things where I am I don’t have the space to do a breezeway. But it will have its own standalone HVAC system.

The shop and the house must be separate systems. I was talking about a breezeway that is not connected to either system. Would give you a buffer zone.

Doesn't have to be large. 6-8' would be enough and still give you a useable entry/storage space. You are going to want a place for coats and boots anyway.

 

[finn]

As long as the structures meet fire codes, and the shop stays at a lower static air pressure, ie adequate ventilation.

That said, I would never consider a shop attached to my primary dwelling. Too high of a risk of losing everything in a fire.

If you can’t separate the shop from the dwelling, either downsize one or the other or find a larger plot of land.

 

[racecougar]

In addition to air sealing, separate HVAC, exhaust, etc., a scrubber will help in a lot of situations. It certainly works well for welding/grinding, and you won't lose your conditioned air. I made these for two of my buildings.

Hanging air filter discussion and recommendations

I already have some box fans with filters and they do a good job but especially when wire wheeling rust it seems to rise immediately so I've been looking into the hanging systems to supplement. My space is 28x28x13 so about 10k cubic feet. I can't decide if I should get a singler larger unit or...

www.garagejournal.com

 

[berntsang]

If you can’t separate the shop from the dwelling, either downsize one or the other or find a larger plot of land.

We tried for a long time. Unfortunately where I am there’s not many large plots and land goes for over a million an acre. That’s if you can find any for sale. We’re on a half acre but zoning doesn’t allow detached garages over 400sqft hence the need to attach.
I’m extremely jealous of all the folks on here with these huge properties multiple several thousand sqft shops etc. unfortunately it doesn’t exist where I am in the U.S. so I have to live vicariously through all of you!

 

[Hilltopmasonry]

Build it as a detached and add a breezeway to attach it.

Might be a little difficult accessing the bedrooms above the garage

 

[Hilltopmasonry]

In order to build my 1500 sq ft garage I had to attach it as well, it’s pretty standard building code

If the garage is properly insulated and drywalled you won’t have too much of an issue, unless you leave the house door open

If doing alot of spraying then a makeshift paint booth would solve it

If a large amount of fumes accumulate, all you have to do is simply open the overhead garage door for a minute

 

[Hilltopmasonry]

We tried for a long time. Unfortunately where I am there’s not many large plots and land goes for over a million an acre. That’s if you can find any for sale. We’re on a half acre but zoning doesn’t allow detached garages over 400sqft hence the need to attach.
I’m extremely jealous of all the folks on here with these huge properties multiple several thousand sqft shops etc. unfortunately it doesn’t exist where I am in the U.S. so I have to live vicariously through all of you!

I am in the same position as you living in the West Chicago burbs. I have just under a half an acre, but I was able to build a 1500 square-foot garage which is very rare anywhere in the vicinity around the here without having to move 30 miles away

Personally, I like having the attached garage because we also park our daily driver in there as well

 

[pcmeiners]

- spray foam. It REALLY cuts down on air infiltration.

Probably the best idea is foam, on the cheap I would have a well sealed vapor barrier under type X sheetrock and a spring closing metal fire code door which has a good air seal .

 

[Hilltopmasonry]

Simpler solution to being the caulking watch dog - spray foam. It REALLY cuts down on air infiltration.

Plus it cuts down on the noise and heating n cooling costs


Even when it is in the single digits my house furnace barely runs and the garage always stays above freezing even without a heater

 

[BroncoAZ]

Segregate the garage into two spaces, one for parking and one for a shop. The garage may get a little fume smell, but I never get anything in the house. My attached garage squares out to 34’ wide and 44’ deep but there is a wall dividing it into two spaces. The parking garage is 34x21 and the shop is 34x23. I have a double door and a 10’ garage door in that wall so I can pull a vehicle into the shop. The additional wall space offered by the dividing wall is more useful than the open space would be there. Another benefit is that I’m only heating/cooling/dehumidifying half the space. I didn’t build it so the ceilings are only 10’ in both, so no car lift. I may do a mid rise in the shop, but I’d want it recessed into the floor to not encumber the rest of the bay.

 

[BurtEggley]

We tried for a long time. Unfortunately where I am there’s not many large plots and land goes for over a million an acre. That’s if you can find any for sale. We’re on a half acre but zoning doesn’t allow detached garages over 400sqft hence the need to attach.
I’m extremely jealous of all the folks on here with these huge properties multiple several thousand sqft shops etc. unfortunately it doesn’t exist where I am in the U.S. so I have to live vicariously through all of you!

does it allow outbuildings / barns used as shops? Put the garage on the house and add another detached building for a shop / barn.

 

[Youngandfree]

Might be a little difficult accessing the bedrooms above the garage

2 story breezeway

 

[JohnX14]

What is being done in the "shop"? I have a detached 2 car garage very close to my house with 2 care attached garage. I call it my shop. I have a ton of tools, do some light woodworking, detail my cars, etc. If I were to do welding or spraying, it has the separation to afford that. But I don't do that type of work. If you are doing any or all of the work as a hobby, the building and zoning codes likely won't prohibit this. But look close at zoning. (I'm a zoning enforcement officer, unfortunately, and a building code official) I still just don't understand the problem you are having. Pics could help.

Edit: I re-read OP, and even given the activities presented, (regarless of whether zoning allows them) adequate ventilation is easily achievable. As long as we aren't talking spraying cars, or catalyzed laquer on cabinets, or other hazardous applications.

 

[loganb]

Fumes travel where there is a leak path and a pressure differential. Manage either one, preferably both and the problem is solved.

Do a bang up job of sealing the garage envelope....walls and ceiling. Depending on the climate will help dictate the best way but air barrier like a Siga product, spray foam etc could all work well

With a well sealed space, then it's managing pressure difference. Keeping the garage at a slightly lower pressure than the house when fumes are a risk will help ensure that errant odors stay out of the house. Basic exhaust fan with a controller could be the start working up to a more complicated setup, but as the exhaust fan gets larger in a well sealed structure you will want to control the quality of the makeup air coming in. So filtration, thinking thru airflow so that ideally that airflow is helping direct fumes to the exhaust.

This coupled with basic fume mangt practices, like closing containers when not actively using them or spraying into filter boxes with paint or finishes should easily achieve what you're wanting