building a cheap structure

so im getting back into woodworking as well as playing with cars. obviously, these two hobbies would not happily share a workspace. so i need a building. ive been kickin around an idea that sounds really good to me.

take a 150 dollar 20X24 carport (metal jobbie thats used local), put it up on a subfloor. build the subfloor out of 2X12 on 14 inch centers, with a double layer of 3/4 ply for flooring and weight bearing. sit carport on top of floor. add studs to the carport, sheet the outsides with OSB and vynil siding to match the house. add a few windows and a large door.

my question is about insulating and sweting on the inside. ill be heating with kerosene, and cooling with a window AC unit mounted in the wall.

why is this a bad idea? is there anything i shoud do differntly? how would i keep condensation due to the metal roof to a minimum?

thanks guys

michael

I remember from the Quonset hut thread a while back that spray-on foam insulation works well...

By the time you've spent the money and effort to frame the floor and sides and put in windows and doors, I think you'll regret the $150 car port. Making your own trusses and putting on a traditional roof will cost more but look and function worlds better and then you're not working around some short cut. I bought cheap shingles from Home Depot for the garage at the old house. 2x6's, nails, truss plates, sheathing, tar paper, roofing nails and shingles is what you need rather than the car port. Probably $500 instead of $150 but it'll look so much better.

My question would be with regards to your floor. What you describe sounds like a beefy shed-type floor, which might work if supported properly. What do you plan to put this on? Bare earth? Bed of gravel? Concrete pylons or blocks? You want to be careful or the flooring will settle over time - and it won't do so evenly, leading to a whole host of issues.

Additionally, check the building codes for your area. What you've described sounds like you're hoping to fall under the "temporary structure" provision, but there are usually square foot limits as well as limits when you bring power into it. And just because you may be in the sticks, don't assume you have carte blanche to do whatever you want. Even my g/f's uncle needed a permit and inspections to build his 30x30 pole barn in the mtns of PA where they don't even have a post office or f/t police.

Ian F wrote: Additionally, check the building codes for your area. What you've described sounds like you're hoping to fall under the "temporary structure" provision, but there are usually square foot limits as well as limits when you bring power into it.

+1

Annoying though it is, this has the potential to be the biggest grief of the project.

Apologies if you're already on top of this, I know it wasn't the question which was asked, but I had the same thought as Ian on the sounds of hoping to slide in on "temporary structure" rules, and some places are real sticklers about that stuff.

You defintely want to check into code issues first. I don't think the floor will be strong enough to support a engine hoist or similar, not to mention unless it's well ventilated it will rot quickly. Setting the wood directly on the ground would accelerate that to the point where you could probably watch it rot. By the time you get done buying the 2x12's and 3/4 plywood, you could use the same money to build a form and pour a 4" slab.

see, this is why i go here to bounce ideas off of you guys. i didnt even think about permits or anything. the plan was to put the flooring on pylons for air movement.

this would be a woodshop, so the floor would have to support things like a tablesaw, planer, lather, etc. thats why i was thinking of 2 3/4 sheets of ply for load bearing.

before i think anymore, i need to look into seeing oif the city will even let me consider this.

michael

There are a lot of problems with this idea.

Start with your building inspector. He will set you straight.

Dusterbd13 wrote: I'll be heating with kerosene.

If you're talking about an unvented space heater, include a carbon monoxide detector in your budget.

I have hopes of building a similar sized shop in my back yard (local coverage codes permitting...) so I totally understand the desire to minimize costs. But keep in mind, if you invest in building the shop properly, it can be a long-term value-adder to your property. Build it on the cheap and it may work for awhile but in the end be a liability.

Look in to building it out of old shipping containers, you can get those super cheap and all you'd have to do is connect them.

My wife and I are planning on building a good sized house/garage out in the country with them after we retire.

You need one of these. They are unregulated in most areas, which is why I have one.

In a similar vein what should I expect to pay for a poured slab 14 by 20? Would do myself but seems like a lot of work. Not even aware of what I would do to the ground below to prep for concrete.

Seems the OP has a good start though for what he wants to use the space for. Would plastic sheeting or some such thing on the gound help with rot issues?

vwcorvette wrote: In a similar vein what should I expect to pay for a poured slab 14 by 20? Would do myself but seems like a lot of work. Not even aware of what I would do to the ground below to prep for concrete.

With all due respect, if you are not aware of what to do to prep the ground for concrete, you are probably not ready to pour your own floor. There are a lot of ways to screw it up. Concrete finishers work pretty cheap.

vwcorvette wrote: Seems the OP has a good start though for what he wants to use the space for. Would plastic sheeting or some such thing on the gound help with rot issues?

Plastic sheeting- very bad idea. It is a vapor barrier, not a rot preventer. If it pooled water runoff from the roof, it would greatly contribute to accelerating the potential for rot. Pressure treated ground contact wood.

There is nothing wrong with a carport for a carport. It is not a building. It is not designed to support weight of a ceiling, cannot be insulated well without creating problems with weight or ventilation, has no foundation, Has insufficient height, cannot be well anchored against wind lift, can be a fire trap if the insulation is left exposed in a wood shop, and heating with a kerosene heater in a sawdust environment that is unventilated is a monumentally bad idea. Other than that, I guess it's a good start. (serious sarcasm).

If you'd like to use the carport as-is as a covered outdoor shop, it will work fine. Other than that, it violates pretty much all of the building codes.

Please talk first to your building inspector, and then someone who understands construction.

SVreX wrote: There are a lot of problems with this idea. Start with your building inspector. He will set you straight.

Or make your head spin with stupid codes and permit requirements...

But a trip to the building dept with your wishes will at least give you a list of what they want

Slabs vary depending on different stuff including access. I paid $2k for a 26x26 4" slab with a 6" drop edge (thicker on edge for higher load capacity) including having the footing dug. The concrete had to be moved to the form with those power wheelbarrows, if there had been direct access for the chute it would have been cheaper.

I have also dug and poured them myself, you can save a good bit but it does mean you have to put a lot of effort into it. If you have access to a tractor with a box blade that will greatly simplify site prep. The site should have thick plastic sheeting as a moisture barrier, otherwise ground water can 'wick' up through the concrete.

You also need to carefully consider drainage, if water can't get away from the slab quickly it will soften the ground under the edges and lead to the slab cracking. That's not necessarily the end of the world, but it's a damn sight easier to fix during the planning stages than after the building is completed.

I built a 10x10 storage shed with 2x4's and treated 'T111' sheathing which was on a slab I poured myself, IIRC when all was said and done it cost me ~$700.00. That was small enough that the roof did not really require trusses, but any bigger than that I would definitely recommend having real trusses made. If it's a standard size and pitch (roof angle) they can be surprisingly affordable.

I built my last shop with 2x4's, OSB and vinyl siding (had to match the house). I prefer that because you never have to paint the vinyl siding and I am basically lazy.

OBTW, a shop won't necessarily add value to a house. Around this part of the country, if you build it yourself you will most likely recover your materials cost at sale time, if you have it pro built no way. Now here's the flip side of that: with a nice shop on the property the house will likely sell faster. Yeah, I know, weird.

In reply to mguar:

On the green 'mill run' lumber, did you have warpage problems? Reason I ask, a friend of mine got a bunch of mill run down here (sorry, don't know what species), built a fence from it and after about ten days half of it came down by itself because the wood warped from sun exposure followed by rain.

bah. my entire bedroom and kitchen are knotty pine including the ceiling. i have found all the infinite patterns in my bedroom ceiling. i'm not so much bored as i am tired of feeling like i sleep in a giant coffin.

mguar wrote: Every few years women paint walls and buy rugs and curtains because they are bored of looking at the same color.. If they only knew that with the infinite pattern and figure of wood to look at no such boredom occurs..

Uh, wow. Here I was reading and enjoying this thread, and suddenly I am reminded I can't possibly understand any of it. I probably never even noticed the wood grain on any of the furniture I've restored. Guess I'll go back to listening to the whale sounds that pass for inner thoughts in my head.

Margie

yup keep yourself out from under the patio is a good idea ;-) lol

I've done a lot of timber framing. It's a beautiful, nearly lost art. I turned down a position years back with Benson Woodworking.

For the record, however, this is an incorrect statement:

mguar wrote: It's called timberframing and meets all building code requirements..

It technically doesn't meet ANY building codes. Building codes require all structural members be stamped by a lumber grader to insure they meet the stress grade. Mill cut timbers do not have grade stamps, and some species (like oak) only have grading for appearance- allowable stress grades have not been developed. Even if you can reasonably demonstrate that the timber frame exceeds the code requirements by a factor of three, the building inspector does NOT have to let you build it.

That's why most modern timber frame structures utilize the services of an engineer.

Granted, many inspectors will allow it. But they don't have to. It's not in the code.

I would also be very hesitant to recommend timber frame construction to someone who wants to infill a metal shed roof. Timber framing requires a level of expertise that is fairly advanced. Typical stick frame construction is significantly easier, and much better documented for the amateur builder in virtually every DIYer book ever written.

It sounds like you built a very nice home.

However, my statements about the building code (at least regarding the IBC) are correct. I have read it nearly daily as part of my work for over 30 years, and have an intimate understanding of it and its revisions. I am very capable of routinely challenging most building inspectors and winning.

As I said, most municipalities will allow it, but none are required to.

BTW, the UBC was only applicable in the Western United States, and was retired in 1997. It was replaced by the International Building Code (IBC) in 2000 merging the codes of the ICBO (which published the UBC), the BOCA, and the SBCCI. It is not the building code by which modern houses are judged.

You might need to update YOUR understanding of the building code.

Tedd Benson has an entire engineering department. I've been there. Everything they do is engineered, including their SIPS. Bad example.

Sure there are legal precedents. How many folks want to settle their issues with the building department in court? Especially for a backyard shed?

The Building Code does not offer the only permissable methods of building. It gives guidelines for building officials to follow which are STANDARDS, and which they may approve without further professional input (like an engineer or architect). They are not engineers, and not qualified to approve things outside the code (it's all about liability).

Everything can be overridden if someone is willing to put their seal on it and go to court.

If you actually care, you need to read a little more in the code about the authority of the local building inspector. It is very broad and all-encompassing. Bottom line: He doesn't have to approve anything he doesn't want to. I know that is an oversimplification, but it is absolutely true.

Please note this thread is about building cheap structures. I know you got plenty of bargains, but you are not addressing the OP's question. Timber frames are NOT cheap. Ever. Especially when you do double timber framing, SIPs, etc.

im actually learning quite a bit that was outside the topic of my origonal ideas. i was trying to find the quick cheap, and easy way out. y'all have successfully talked me out of it.

and as a clarifier, i built mortise and tennon furniture, cabinets, and various other furniture for a living for the last 7 years. not a homebuilder or contractor, which is why i came to ask you guys. im really bhuilding this shop for a place to turn bowls and such, as ive really begin to enjoy and look forward to wood turning.

SVreX wrote: Bottom line: He doesn't have to approve anything he doesn't want to. I know that is an oversimplification, but it is absolutely true.

Yep. In the construction engineering trade, we refer to this as the "Authority Having Jurisdiction". He/she can require something more if they feel strongly about it (I have to call one regarding AFCI requirements) and let certain things slide if fixing it would be prohibitively expensive - like how the electrical inspector didn't even venture into the basement since A) it technically isn't in the scope of the renovation, and B) being a 120+ year old house there are more violations down there than I can count and fixing them would basically require re-wiring most of the house.