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Is Wood Construction Realistic Option for 4200 foot new Shop?

markz528

Hot Rolled
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Sep 25, 2012
Location
Cincinnati
Building a new shop. No idea what it will look like yet from a layout standpoint, but thinking 60 x 70 with 12' high walls. My machining supports my drag racing hobby, so shop will be a combination auto workshop, car storage and machine shop. Currently machine shop is an Atrump CNC bed mill, 16 x 6' lathe and hydraulic surface grinder.

Started discussions with metal pole barn builders, but is wood construction even an option in this size? Would it be cost competitive? Advantages? Not too keen on heating/cooling 4200 square feet if only 1000 or 2000 needs to be routinely environmentally conditioned.

Any other feedback?
 
At that size metal buildings are pretty affordable. I like wood because I know how to deal with it myself.
I would go with a metal building with higher walls.
12 foot gets short quick. 14-18 foot walls means you can put a second floor anywhere you choose.

insulate well, and heating is less of a problem. 2inches of foam at the perimeter of the foundation, including across the doors.
 
I can go a little taller than 12 but its more heating space and my setbacks change quite a bit for every foot taller than 18'. The calculation is pretty weird, but with 12 foot walls at 4:12 pitch (don't know if that is enough or not for a metal roof) came in a tad under 18 feet.
 
There is the fire danger thats higher in a wood shop. right now a steel building is probably cheaper. but metal buildings the concrete is usually a mono pour and that is fairly expensive to get done. My brother is trying to get a pour done 30x 50 mono pour and has had multiple quotes over 30000 for just the concrete. A wood building having the studs sure make it nice for shelving and attaching stuff
 
Tons of variables. A lot of it geographic.

One aspect to consider is that you can very often buy steel building frameworks used for very low prices. Low enough that painting and engineering can be redone and still be way ahead of wood. Wood building components don't usually fair well upon disassembly.

I don't believe there's much of a difference in concrete costs for a given size. If you are talking pouring the most basic of slabs in a pole building then, yes, that's way cheaper than stick frame or steel. A stick build wood building is going to have a substantial monolithic slab.
 
If you go metal 1:12 standing seam will give you more headroom while keeping the peak down.

I hate second stories. Consider a lean-to for office space.
 
Metal roofs are usually lower pitch. Probably 2 in 12

You are not going to easily clear span 60 feet in wood. 60 feet wide at 12 foot high is super low

Not sure what your zoning rules are, even at 12 foot with a 4 in 12 that roof is 22 foot high. If a metal building was 2 in 12 it would be the same height with a 16 foot wall
 
Knock that 60' width down to 40' with a lean-to on each side.
You can put purlins inside at the 40' width, having the outer sides un-heated.
These will also be un-moving air, so a buffer to the heated inside.

40' clearspan in the middle is cheaper as well.
 
Knock that 60' width down to 40' with a lean-to on each side.
You can put purlins inside at the 40' width, having the outer sides un-heated.
These will also be un-moving air, so a buffer to the heated inside.

40' clearspan in the middle is cheaper as well.

Unfortunately I need 60' depth because I will be parking an RV with trailer in the shop and that is about 55 feet long total.

And the height calculation is weird. It is not to the peak of the roof. It is like halfway to the peak.
 
You really need to dig into your local zoning rules. I have had a couple of pole buildings put up and things vary a lot just across the same state. Sixty feet wide is a real potential issue with wood construction. Those trusses may not even be able to be engineered at that span. The ideas of the two lean-to's on the sides may make the thing more feasible. Go narrower if possible to simplify things.
 
My thought is that if you can stand a set of center support columns, you can get the 60' in wood trusses.

Some care should be taken with posts (e.g. wood in the ground) so you don't get burned in 30 years. PermaColumns are excellent. There's also a better treatment standard, UC4B would be very minimum for posts that touch the earth. Post frame is harder to wire and insulate.

That's a big building and I would expect your final price tag to easily touch $30/sf so north of 125k.
 
Unfortunately I need 60' depth because I will be parking an RV with trailer in the shop and that is about 55 feet long total.

And the height calculation is weird. It is not to the peak of the roof. It is like halfway to the peak.

So turn the building 90 degrees....duh
Your "RV parking requirement" is better suited to a "lean-to" unheated,
from the main shop.
It also isolates it from the shop dirt (welding arc, grinder dust, paint spraying, etc.)
 
Wood is a very viable option...just ask Morton Buildings. Whether you choose to use wood or not is up to you. Pro's are wood would be quieter, easier to work on, and generally better insulated. Cons might be cost and speed of erection. IMO a wood building with a standing seam metal roof would be the hot ticket and also have the best resale value. To many buyers, a wood shop looks like a 'real' building and a metal shop looks like an ad-hoc building.
 
Lots of wood post frame buildings this size and larger on farms. Many now have 18+ foot side walls. The questions you need to ask are how does it price out compared to steel. What are the local zoning/building requirements for these buildings (this will vary depending on if the location is "commercial"). Also what are the insurance impacts. Your agent should be able to tell you that right away. In any building a door in the gable end is cheaper than the side wall (load bearing beam not required)

A 12 foot ceiling is a little to short for a shop and certainly for RV storage. Most builders will only put a 10 foot door in a 12 foot building (approx 11-6 actual height after the floor is poured). You also need lots of head room for a auto lift and any rolling gantry crane. A class A motor home needs a 14 foot door.
 
60ft clear span engineered wood trusses is not a big deal. I finished up my shop last year that is just a little bit larger than yours, it's just a few feet larger in each direction with a 12ft ceiling. Wood framed with metal siding and roof. Fortunately the lumber was purchased prior to the crazy price increases.

One thing to keep in mind is that you can get those large trusses to the job site.
 
I think that the larger the building the more cost and other advantages you have with steel. Costs probably vary a lot by area. In the south where you don't need deep footins the concrete cost between the two may not be much different. In the north the concrete will probably be significantly more. You can do long span wood trusses, but the cost probably increases exponentially. If I were you I would look at both options. If they were close in cost I would go with steel.

With either building construction details and critical. Long span wood trusses can easily collapse if not braced properly. Metal building roofs sometimes fail from snow loads, which should not happen if properly engineered. I have never looked into the cause. It may be construction related. Some people think that the tension rods used in steel buildings are only needed during election. They are needed for shear bracing.
 
My 5,300 sq ft shop is a wooden pole barn. The main room has a 60' span, 50' deep, with shed overhangs on two sides. It has radiant heat throughout, and I cool the entire building with a 2.5 ton air conditioner.

15'6" ceiling height in the main shop and an insulated 6" thick reinforced concrete floor.

The building is hyper-insulated, with 16" of fill in the walls and 36" in the attic. One shed side has 8" of open cell spray foam. This is the reason why I can heat it with a 40 gallon water heater and cool it with a 2.5 ton AC unit.

I have a 400hp generator that produces 480V three phase, and I step it down so that both 480 and 240 3 phase are available. There is also a 30hp rotary phase converter on a transfer switch so that I can supply 240 3 phase either from the generator or RPC. This also supplies my machine shop, which is housed a couple of hundred feet away in an old log cabin.

Everything was built by myself and my farm hands, with the exception of the concrete pour (I wanted a higher quality result than what I could achieve myself), and some of the framing. We did all of the prep work for the pour including pouring the retaining walls, as well as the insulation, reinforcement and radiant heating installation.

QSO_Aerial_1_compressed.jpg


In this pic I'm setting the last truss. I'm operating the crane, and my foreman is in the manlift.

last_truss_compressed.jpg


QSO_slab_compressed.jpg


QSO_radiant_heating_and_slab_pour2.jpg


A 60' wood truss is not a problem, but they need to be well braced as they are installed. Here I am installing the first truss.

https://www.practicalmachinist.com/...w-shop-setting_the_first_truss_compressed.jpg
 

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I would worry with that big a roof about snow pushing in the walls. You will have to push the snow away from the walls after every decent size snow. Either that or massive overhangs roughly as wide as the wall is tall.
Bill D
 
The good thing is when you want it gone you can get rid with a welding set and a bit of hidden rubbish under a bench, it does burn so well, scary fast
Mark
 








 
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