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Discussion Starter #1 (Edited)
With a heated shop is there any benefit or downsides to putting in a scissor truss design. It will give more head room but is it harder to heat, get out exhaust out of the building, etc. If you used a scissor truss what was the inside pitch of the ceiling?

As far as engine exhaust what is the easiest way to get it out of the building when you are pulling something out of the shop?

For welding what is the best design to get rid of the smoke in winter when welding inside?

Has anyone incorporated some sort of overhead moveable chain hoist into the bottom of wood trusses or another type of overhead hoist that can be moved to lift things in different parts of the shop?

For vehicle lifts like a 2 pole lift where is a good place to situate this so it does not waste a bunch of space? Has anyone put in a larger 2 pole lift like a 20,000lb to lift highway trucks and if so how well does it work?

Any thoughts or comments on any of these questions would be appreciated. Thanks SouthernSK
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Can't yet speak from experience but we just started heating our shop with a peaked ceiling and open trusses. No attic. There's a ton of space up there for heat to gather. We will be putting in some fairly large fans to push the hot air back down and try to keep it all mixed. But as for smoke, we have two 24" exhaust fans up near the ceiling level. There's a vent on the other side of the shop, or could just raise the door a crack. Based on our experience with getting smoke out of a very large quonset-style shop, that should work fairly well.

Haven't tackled the welding smoke issue yet, but I think the best system, albeit the most expensive, is a fume extractor that filters the air back into the room instead of putting it outside. The problem with fume extractors that exhaust outside is it blows your warm air out.

I've been thinking a lot about two post lifts and I've decided I don't want anything permanently fixed anywhere. So what we might do is embed some female anchors in the cement in one area and then rig the post lifts up so that we can move them into place and bolt them down when we need them. We don't have any extra reinforcement in the floor so such a lift would be for cars and small trucks only. For the big trucks I'd dearly love a set of mobile column lifts, but those are way expensive! Only about $45k for a set of four.
 

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I can’t imagine a truss design out of wood that could support the snow load like that. That’s what is pushing us towards a steel building is that’s the kind of roof I’m looking for.
 

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Discussion Starter #4
If you put the wood trusses on two foot centers you can go up to 90 feet wide on the truss. After about 70 feet wide they go to a 2x8 top and bottom cords. A 2x8 is over twice the strength of a 2x6. I was thinking of going on two foot centers with the wood trusses and sheeting it with 5/8 fir plywood before we put the metal roof on.
 

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if your in cold manitoba like we are an open ceiling will just loose more heat imo.
as far as welding smoke etc, buy an old furnace with 4 filter housings and have suction along the centre of the roof and the exhaust (clean air) on one end of the shop so you kinda get an air circulation. Putting large fans on the roof will just push the exhaust fumes and cold air down especially when you have floor heat.
we have an range hood design above our welding/plasma cut table with a suction fan above the range hood and then ducting with fans towards the exhaust fan of the shop. Works good, but doesn't help as much when your plasma cutting in the shop itself, we usually try to plasma cut outside if its a rusted frame.
for engine exhaust we have a heat resistance hose we can slide over the exhaust if the piece of equipment needs to run in the shop.

as far as car lift goes, i'd either get a mobile one or build a pit in the ground, we have a pit in the ground and its nice for semi trucks and trailers to work underneath, make sure if you build a pit you build lights in it. sucks always needing a flashlight.
 

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To insulate properly a ceiling would be much better, I think that a open truss would have more heat at the peak. Infloor heat might help to keep the heat even from top to bottom, it does in my shop with 21’ ceiling. One 24” or bigger fan should be enough to change air, make sure you ha e a inlet for the air kitty corner to the fan.

As far as a car hoist if I were doing over again I like this.

161574
 

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Discussion Starter #7
Thank you for all the great ideas. Windmillfarms the hose that you use to collect the exhaust when running a engine is it suspended from the ceiling and does it have a suction fan on it? Do you have any pictures of this?
 

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In floor heat changes everything IMO. Heating air is such a waste of energy as air retains little energy and rises instantly. Heat the floor and energy remains there much longer. Open a huge garage door for 5 min in a shop heated with forced air or radiant heat. Then do the same in a floor heat system and close the door. The heated floor building will win everytime on initial warm up. Just like southernsk's fire place in another post, you can insulate a shop and save heat but your energy form and it's ability to retain heat is key. With floor heat you always insulate under the slab. Not many do this in a forced air system. They all concentrate on the ceiling as their primary heat loss. That isn't where you are though and can feel cold down 15' below. I know my house floor is extremely comfortable on your feet. If you get real cold outside and need to warm up just lay on the floor lol. My garage on my house is the same temp by choice so if I am changing oil or working on the floor I leave a garage door open 5": Otherwise I would melt. My heat source is pretty much free with a bale boiler so I am wasteful always.
 

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In floor heat changes everything IMO. Heating air is such a waste of energy as air retains little energy and rises instantly. Heat the floor and energy remains there much longer. Open a huge garage door for 5 min in a shop heated with forced air or radiant heat. Then do the same in a floor heat system and close the door. The heated floor building will win everytime on initial warm up.
If you would have said 50 minutes instead of 5, I would have agreed with you.
Buildings with adequate "air heating systems" still heat the floor, it just takes longer. Radiant tubes will heat the floor too, but only if it is not covered.
If the door is briefly opened, I'd put my money on the furnaced heated building. The heat is still retained in the floor, and all other things in the shop, and has the air temp supplemented with the furnace.
Now if it was left open for long periods of time, maybe that would be a different story.
 

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I find the recovery slow in our shop with heated floor depending on what door I use. My 16 x16 overhead takes about 5 - 10 minutes to recover while my 20’x 40’ hydraulic door will need more than a hour to recover. We will try to use the big door at the end of the day or go back to the house and have a coffee for a bit while temperatures recover.
 

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Open a huge garage door for 5 min in a shop heated with forced air or radiant heat. Then do the same in a floor heat system and close the door. The heated floor building will win everytime on initial warm up.
From a physics perspective, if you keep the shop at a constant temperature, the effect is nearly the same regardless of how you heat it. The thermal mass of the floor re-heats the air. I have a forced air furnace in a small shop that we keep at a steady 15C all winter. We can open the big door and it recovers quite nicely because the floor, walls, and everything in the shop is warm, nearly at 15C. Might even recover faster than in-floor because as well as the warm floor helping to heat the room back up, the forced air furnace is mixing the air also.

Back in our old machine shop that we only heated sometimes in the winter, a forced air furnace was never adequate because everything in the shop acted as a big heat sink. Once we started keeping the furnace on all the time, even to just 5 degrees, everything got better and it was so much easier to recover the temperature when we opened the door.

I know the idea of ceiling fans has been poopooed here (yes you don't want them to run when you've got diesel smoke in the building), but they are key to heating a building by any means where the ceiling is greater than some height, say 18 feet. And they would certainly help a building recover by pushing hot air back down. You'll get hot air accumulating near the ceiling even with in-floor heating heating from the bottom up.
 

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when we were building our shop a couple of years ago we found that there are less than 2° difference from floor to ceiling this is in a 21 foot tall building using a heat gun. We did still put 4 ceiling fans in that run low all the time.
 

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If one was using forced air there definitely would be a lot more gradient. Radiant would depend on what is sitting on the floor (machines, etc). I agree that in-floor heats more evenly in a working shop full of machines. But I think for us radiant is a good compromise.
 

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A mechanic I know that works in a large truck/oilfield fleet building that I believe is forced air heated and said the floor or floor zone anyway would get cold due to doors randomly being opened through the day and for some reason they were not using their ceiling fans to mix the warm upper air with the cold low zone as he said that makes all the difference in that type of setup. I am assuming as well that on a floor only heated building the recovery time would drag on due to the slowness of a heated surface transferring heat to the air and again fans would circulate the air to help transfer that heat sink of the floor into the air. Seems to come down to having floor heat and supplementary forced air heat along with fans to get that air temp back up in a more reasonable amount of time if doors are going to be opened very often.
 

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Yes I think you're correct. Some combination would be ideal. In the end we went with straight radiant, and so far we're pleased with it. Time will tell.

A warm floor will of course warm the air mechanically, but there also is infrared radiation coming off of it which will also warm walls, objects, and people.
 

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If a person could afford all the fancy commercial building options, having a heated air curtain system at each door would be a really slick solution to helping prevent a lot of heat loss and chill in the shop with a door opening and having to stay open for any period of time to move equipment. I had mentioned this in the past but a few years ago happened to be in the back of a supply warehouse for the oilfield ( and farmers etc ) and it was quite cold out and they had their shipping/receiving docking door wide open and I could stand right there just back of the air flow and feel totally warm, stick my arm through the invisible wall of air and ice cold on the other side. That was something they had installed in later years as it used to be cold back there if they had to have that door open. What a game changer such a piece of equipment is for that type of situation.
 

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No shop I worked in had in floor heat. I think it would be great in a commercial shop where you are working 8hr a day every day.
I worked under forced air furnaces overheads thought there were 6? well they are noisy enough when its -40 and trust me most of them are running at -40.
The tubes are quiet but that is the only good thing about them.
Tubes are slow recovery, ceiling fans always running overspeed to distribute the heat, too hot under the tube and 2 feet over everything is cold, just terrible to work under, go on top of a combine under a tube and see how you like it, of course an automotive component tied to this shop too and that didn't help [email protected] door was constantly opening and closing.
Friend owns the one machine shop and it has in floor heat, however he soon found out recovery time way to slow also and I pretty sure they tied in some hot water overhead rads with fans into the system to speed up the recovery time from the door being opened and turned down the floor heat some, too hot on the feet standing at the lathe all day long.
Thing is if you have to have supplemental forced air overheads then in floor kind of looks like a large extra expense.
edit,
But then again for a farm shop where maybe you aren't opening the door every 30mins for an oil change car maybe a guy could get by with just a radiant tube heat.
It all depends how much of the time are you going to use this shop in the winter?
 

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I have in floor heat in a 50x100 shop. I absolutely love it. Same temp from my feet to the top of the shop. Maybe 1 degree difference. Maybe. I keep it at 61F. But we don’t open the doors every 30 min or so. Maybe 5 times a day.
My doors are from the north. If there a wind the shop dose cool down to 57F or so.
 
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