New member building a new garage

[NS Gearhead]

Hi everyone! Greetings from Nova Scotia, Canada. I'm currently in the planning stages of my garage build, and thought I'd run it by this forum just to make sure I don't miss anything or make any mistakes.

I'm still not 100% firm on these details, but I'm narrowing in on them; Cape style, 32x32, 12' walls, 6"-2' concrete pony wall (subtracted from the 12'), two 10x10 doors, allowance in the pad for a two post hoist in the right bay, floor drain in the right bay, 200amp service, multiple 110/220 outlets in the left bay (shop space), stairs at the back of the right bay, significant "hatch" in the ceiling rear most center (for future lift). I'm assuming from what I've see online is that the roof will be 12/12 pitch, there will be 4' knee walls upstairs 4' out from the edge, so the space up there will be aprox 24x32. I was thinking heat pump for the main area, and nothing upstairs as it's just going to be storage to keep the main area uncluttered, but, people are telling me to run the in-floor pipes just in case I want to go that route later. I'd like a giant wall mounted exhaust fan, as I do a lot of grinding, and my current attached single car garage is COVERED in a layer of it.

So some questions; The thought is to have a workshop on the left, parking/ hoist on the right. Is a square building a good choice?... or would rectangular be more beneficial? Should the hoist be centered front to back, or set farther back? Cape style a good choice or go conventional two story? I'm not really limited in size and height is 35' max. I just have to put a limit somewhere for the budget. I want waterproof interior paneling; recommendations? How would I keep the exhaust fan insulated? I was thinking of perhaps making two insulated cabinet doors that could close over it when not in use.... Sorry for the long winded first post. I'll be reading through the archives and looking forward to replies. I've attached a couple of internet search pictures that kind of show what I'm talking about.

 

[wssix99]

Lots here, but some food for thought:

allowance in the pad for a two post hoist in the right bay

The only allowance you need to make is pouring the entire pad to the proper thickness. (and make sure your contractor doesn't cut corners on that) This is what ALL the instructions for ALL the lifts tell us to do for very good engineering reasons. You'll see posts where people thicken slabs and try to put in exotic footers for lifts, but this is not the correct thing to do. (Modern lifts do not need "footers".) These off-label techniques heighten the possibility of slab cracking, which makes things weaker.

floor drain in the right bay

Do you really need this? These come with all sorts of issues. Grease traps, explosion hazards, and the penetration in the middle of the floor requires that some of your saw cut joints go through the point the drain is installed. The latter could cause you complications for where you want to put your lift. (Lift legs need to be a certain distance from cracks and these saw cut joints.)

200amp service

Good choice, especially if you are going to charge electric vehicles in the garage. If not, 200 amps is overkill. If so, you'll want to be sure to make allowances for charging stations or pulling wire at a later time.

people are telling me to run the in-floor pipes just in case I want to go that route later

If you are going to heat the garage 100% of the time, this is a good idea. If you will never heat the space all of the time, this type of system isn't for you. (It takes a long time to heat up the slab before it starts heating the room if you start with a cold room.)

Should the hoist be centered front to back, or set farther back?

This depends on the design of the lift and the vehicles you will be lifting. You'll need to map out the center of mass of your vehicles and the placement of that center for your lift and then work out the placement. One big concern you should work out is where your saw cut joints are going to go and what kind of distance you need to keep from the posts.

There are lots of great posts here about 2 vs. 4 post lifts. If you are like me, you will grow to hate your 2 post lift very quickly. 4 post lifts are a lot easier to work with, especially as you get older.

How would I keep the exhaust fan insulated?

Whole house fans have allowances for this, but grinding dust gets electrically charged. Unless you are working on a bench with a purpose-built fume extractor, I don't think your problem will be solved: https://kemperamerica.com/product/grinding-tables/

 

[NS Gearhead]

Hey, thanks for taking the time to reply! That's an interesting position about the pad. So my understanding is that I'll need an engineered slab. This basically means that there's a footing all around, then the slab starts thick inside that, and goes to 4" in the center. I will most certainly discuss this with the engineer that designs my slab. I suppose I don't really NEED a floor drain, but the alternative is a floor that slopes the entire length of the garage to shed melted snow and slush I bring in with the vehicle. 200 amp service is because I'm getting more into metal fabrication and will be needing lots of juice for welders, plasmas, lathes, etc. I certainly plan to keep the space above freezing consistently... though not warm like my house. Wouldn't a 4 post kind of exclude that space as a parking spot? I can see me wanting to put my truck plow against the far wall past the hoist.... that wouldn't work. I'm currently driving a plain old silverado, but in the future I might go up to a 3/4 or 1T.

 

[wssix99]

So my understanding is that I'll need an engineered slab. This basically means that there's a footing all around, then the slab starts thick inside that, and goes to 4" in the center. I will most certainly discuss this with the engineer that designs my slab.

Ah - yes. Thickening the edges/outisdes, as in your engineered slab is OK. The problems develop when you make thicker parts in the middle. (It creates problems when the slab cures and shrinks.) Of course, if you have an engineered slab, you can design anything, but exotic stuff is expensive. The bottom line is that you don't need any thickening of the slab for the lifts. They are designed for a plain, flat surface. However; if you have an engineer designing the slab, you should definitely point this out to them and provide them with representative specs/instructions of the lift you plan on installing.

The base plates of the lift are close the contact patches of a car's tires, so the vertical loads of any modern lift shouldn't be a concern to you or your engineer. However, the 2 post lifts impart bending forces on the slab, which your engineer may want to consider in their reinforcing/poststressing plan. (This is another reason why 4 posts rule the day for me. No bending forces. they act on the slab like a giant table sitting there.)

I suppose I don't really NEED a floor drain, but the alternative is a floor that slopes the entire length of the garage to shed melted snow and slush I bring in with the vehicle.

Yes. Your floor should do this anyway. Typically, code calls for garage floors to slope downward towards the garage doors. Not for water/snow melt, but for gasoline vapors. Gas vapor is heavier than air and the slope evacuates any vapors so you don't get an explosive environment in the garage.

Floor drains collect these types of vapors and funnel them under the floor... Some municipalites outlaw them for this reason (like mine) and others require that people vent the drains to air above ground outside the building. (Instead of draining to a sewer or septic system.) Then, some municipalities require that grease traps (very expensive to install and maintain) be installed to trap oils and grease before going into the sewer. So, there are lots to sort out with floor drains. Even if allowed by ones municaplity, there are still scenarios to think about.

If you do a drain in one bay and not the other, then you'll need to figure out a hybrid slope combination to address gas vapors for both bays. (A perfectly flat floor is not the safest choice, even if your local code allows it.)

200 amp service is because I'm getting more into metal fabrication and will be needing lots of juice for welders, plasmas, lathes, etc.

You only need 200 amps if you are using all those things simultaneously. You can have 400 amps of outlets and breakers on a 100 amp service. No problem.

I certainly plan to keep the space above freezing consistently... though not warm like my house.

I'd recommend installing the PEX piping then. I have radiant heat in my garage and its wonderful. You'll also want to insulate under your slab for this eventuality and that's some extra money. We keep our garage at 55 degrees for very little money, but it's highly insulated and attached to the house. (So that, helps lower the cost/loads, also.)

Wouldn't a 4 post kind of exclude that space as a parking spot? I can see me wanting to put my truck plow against the far wall past the hoist.... that wouldn't work. I'm currently driving a plain old silverado, but in the future I might go up to a 3/4 or 1T.

No, just keep the lifts up and park underneath. I keep boats and trailers stored on them during the winter and park underneath:

I'm not sure what would limit you from placing the plow. Just about everything in my garage is on dollies or casters and we roll it all around the posts.

The other thing with a 4 post lift is that you can put the actual lift on casters and move it around. No need to bolt it down. (I would not store things on top long term if not bolted down, but if you need the flexibility, you can roll it around your space and not be tied down.)

 

[Ak Jim]

I can’t imagine not having a floor drain in the garage. Not sure I’d even want a garage with out one.

 

[NS Gearhead]

Problem is I don't have a hoist, or know what one I'll be getting. This is just planning on it for the future. I'm assuming that if I just bump up my center section to 6" from 4, then I can likely put most hoists anywhere. Going to 8" may be cost prohibitive. Yes, duh, keep the 4 post up. No idea why I didn't think about that. LOL I'll have to see what the cost difference between 100 and 200 amp service would be. I just assumed you needed enough to be able to run all, or most at the same time but code. Yeah, floor drains aren't really allowed here either, but I'm told concrete guys can hide them until after inspection.

 

[Crabman]

NS

Sounds like a good project.

I agree with wssix99 that the two post was better when I was younger!

Just stopping by to welcome you to GJ.

Bruce

 

[wssix99]

Problem is I don't have a hoist, or know what one I'll be getting.

I figured this out during design. At least settle on a brand and you can make sure you get your heights correct. For example, 12' ceilings would be too short for my BendPak 2 post lift. However, if you go down the path of a 4 post lift, height doesn't matter so much. From what I've seen, the brands don't evolve their dimensions much over time.

The other thing you need to account for is the sloping for your drains and/or your floor without a drain. If your walls are 12', then you will only see that true height at the garage doors. The floors slope up from that low point, so the middle of the room could be 11'-6" and your back wall could be 11'. There are a few posters here who have experienced heartache by planning to the dimension at their doors, only to find that they have less height in the center of the room after their pour.

I'm assuming that if I just bump up my center section to 6" from 4, then I can likely put most hoists anywhere.

This will cause cracking of your floor unless you section the slab and separate the different sections/thicknesses it with isolation joints. (Or expansion joints, like you find in a sidewalk.) You can do this and it's OK. I have differering reinforcement plans in my house slab and did exactly this. (My joints are hidden with partition walls and door thresholds. There are also other products you can use to cap the expansion joint if you don't want to see it. - https://www.pavepatch.com/slabgaske...OoljCphZ_4x3VVEwUhB2c4fiEgDQkRP8aAp_TEALw_wcB)

Cement shrinks as it cures. If the slab changes thickness, then you get differential stresses in that area, which is bad and unpredictable. (The expansion joint breaks this.) You'll see posts here where people have put in gradual transitions in the thickness, but that requires a lot of voodoo and prayer to avoid cracking. Proper design can just deal with it.

Going to 8" may be cost prohibitive.

Indeed. Total overkill.

Yes, duh, keep the 4 post up.

Yea, but we should have mentioned that one needs to take the ramps off the lift when doing this. Its not a big deal and you can even get lightweight alumnium ramps for most lifts if the activity rubs on you.

No idea why I didn't think about that. LOL I'll have to see what the cost difference between 100 and 200 amp service would be. I just assumed you needed enough to be able to run all, or most at the same time but code.

Nope. No limits. The panel has a main breaker that equates to the service, but the breakers on that panel are only limited by the design of the panel. 200 amps is fine for an entire house. We installed a 400 amp service in our house because we made allowances for charging 3 EV's in the garage at the same time. Aside from running a business, (with employees) electric vehicle charging, or having a family that woud run 100 blow dryers at the same time, I can't think of situations where one would need more power.

Yeah, floor drains aren't really allowed here either, but I'm told concrete guys can hide them until after inspection.

I'm sure they can try, but it really boils down to your inspector and if they can put 2 + 2 together and figure out that your floor must be sloping to the center because a drain is there.

I'm sure there is some level of primal satisfaction we get by seeing water "go down the drain". I'll admit, I've been using the toilet for decades and I still pause to watch the swirl. However for the garage, I don't see what the big difference is between water going down a center drain or out underneath the garage door.

Some people here have been worried about garage melt water re-freezing as it exits the garage, but I've never had that problem. (It has so much salt and other stuff in it that it runs off well.) Some have installed slot drains outside the garage to address that concern.

 

[NS Gearhead]

I never thought of the changing height in regards to the sloping floor, or putting a drain in front of the door to address melted water re-freezing! Both excellent points I'll keep in mind. As I mentioned I do plan on having a raised concrete wall around the perimeter, so I could adjust that to make up for this. Primary purpose was just to keep water from being able to seep into the walls. I could do 13 or 14' walls but a little concerned about it looking disproportioned.

 

[Maxcustody]

Welcome and good luck on your new building. @wssix99 Outstanding information. I am building a new shop as well and this has enlightened me to a few thing's as well. I thought I would like a floor drain in both bays, however as stated not worth it and could cause other problems. I also thought about a 2 post lift, but quickly changed to a 4 post for all the versatility. As well as additional dedicated electrical and added concrete costs and concerns to deal with.

 

[NS Gearhead]

Here is a version of the lift I was referring to;

 

[FMB4]

Welcome aboard!

 

[firebirdparts]

I have a cape, house and garage, and what I don't like about it is you can't really seal them up properly, and the geometry is hard to insulate. that would be especially important in a cold climate. The only way you can stop air coming in at the top of the walls is with great care and great attention to detail. Otherwise I like it. I have a "hole" in the second floor on one side which my lift rises into.

 

[NS Gearhead]

I have a cape, house and garage, and what I don't like about it is you can't really seal them up properly, and the geometry is hard to insulate. that would be especially important in a cold climate. The only way you can stop air coming in at the top of the walls is with great care and great attention to detail. Otherwise I like it. I have a "hole" in the second floor on one side which my lift rises into.

Good to know! I was leaning the Cape style way just so it didn't seem so overbearing... but I could look at putting a full 2nd story as well.

 

[CraigStu]

RE; pony wall. As you start talking to contractors consider a block wall. I have had one garage and built one additional bay on another garage done this way. They poured the concrete footers, and built the wall using block. Then the wood walls went on top of the block. The advantage is that no forms need to be used or built like would be needed for a concrete wall. I was going for 10ft ceiling and my contractor said it is always less expensive to go w/ block vs wood. So I got 2ft block and 8ft wood walls. You would go w/ 2ft block and 10ft walls. \
Re; cape style. Our SIL and daughter had their house built in cape style. In this area the house needed to pass a vacuum test to get occupancy permit. They had a bit of a problem getting the short walls on the second floor sealed but it wasn't too difficult a fix. I can see like NS says it may be a little more difficult to insulate but that would only apply to the portion of the 2nd floor walls that are angled and if they are built w/ 2x4s. A little extra planning may be needed there but OTOH it's a garage and no one is living in it.

 

[Yankeefarmer]

I have a cape, house and garage, and what I don't like about it is you can't really seal them up properly, and the geometry is hard to insulate. that would be especially important in a cold climate. The only way you can stop air coming in at the top of the walls is with great care and great attention to detail. Otherwise I like it. I have a "hole" in the second floor on one side which my lift rises into.

Why can’t you seal up a Cape design properly? The house next door is a Cape, mine is a Cape, and my new shop would be termed a Cape. It’s all a matter of where you place vapor barriers and insulation, while still allowing for needed roof deck underside ventilation.

 

[jetnow1]

Pony walls of concrete either solid or block are poor insulation, wick out a lot of heat. They have advantages also, but in a cold climate may not be the best choice if heating the space, especially with in floor heat.

 

[billconner]

Don't insulate the pony walls in an attic. Just have raised heel trusses and insulate under roof. Less sq ft of loss. Fuss with sealing vapor barrier around lower chords.

Expensive but you might look at Superior walls. Did I say expensive? But easy and well insulated, no footing - just gravel. Fast - just a day or two. No finishing required. If you're hiring all the work done, might be a look.

I'm going block but not planning insulation ever. Also DIY easy with surface bonding.

I looked at ICFs but 4x as expensive as plain block, and no benefit to me.

I'm confused by thickened edge unless it's to footing and blocks sit on it. I'm going from footer with block to 2 to 5 courses above slab (cut into slope), and then a 4" slab wall to wall with the fibre board at edge against block. Really good compacting or self compacting pea gravel, best and heaviest vapor barrier I can get, and slab - undecided on fibre (leaning to this) vs rebar vs mesh.

 

[thammel]

I have a 2 post lift and love it. Regardless of which way you go with a lift, do some research.....I went with 12' ceiling height and I wish I'd gone with 12'6" - you will find many 2 post lifts need just a little more that 12' ceiling height.

 

[wssix99]

I'm confused by thickened edge unless it's to footing and blocks sit on it. I'm going from footer with block to 2 to 5 courses above slab (cut into slope), and then a 4" slab wall to wall with the fibre board at edge against block. Really good compacting or self compacting pea gravel, best and heaviest vapor barrier I can get, and slab - undecided on fibre (leaning to this) vs rebar vs mesh.

Best to start a new thread for all of this and folks can point you to information. Lots to talk about here...