Tag Archives: code conforming pole buildings

Converting a Pole Barn to a Residence

Converting a Barn to a Residence

Reader MARK in PORTLAND writes:

“I have a pole barn structure that was converted to a residence without a permit. The slab is 4″ thick with a 4×4 skirt edge around the perimeter. Since the foundation is a pole (pier) system, does the slab edge (non-load bearing) need a thickened lip to extend below the frost line (18″ here)?”

Mike the Pole Barn Guru pole responds:

slab edge insulationWell Mark, as I am sure you are finding out, an entire plethora of issues now exists from the conversion being done without proper permits. Your slab issue just being one of many.

Homes are now required (in most jurisdictions) to meet with energy code requirements. This means you are going to (at the least) have to be adding some insulation below the finished grade of your building. This will eliminate the need to have a thickened slab around the perimeter of your building – which would not only prove to be an added expense, but also a royal pain to install.

I'd approach this challenge with the Frost-Protected Shallow Foundation method, which you can read more about here: https://www.hansenpolebuildings.com/2016/11/frost-protected-shallow-foundations/.

It may take having a RDP (Registered Design Professional – architect or engineer) on board in order to plead your case to the local permitting authorities, who could very well make your immediate future a miserable one should they become angered in regards to the change of use without a permit.

Your building itself could very well pose some other challenges. Most often these come from walls not stiff enough (from a deflection standpoint) to prevent the cracking of any gypsum wallboard surfaces. This is an area which can be looked into by the RDP you are going to hire (please nod your head yes).

Chances are excellent the roof trusses in your building are not designed to support a ceiling load, so you are probably looking at needing an engineered truss repair.

The siding should probably be removed and reinstalled with a housewrap underneath. In the event a dead attic space has been created, the attic area needs to be adequately ventilated to prevent condensation. You can find out more about adequate attic ventilation here: https://www.hansenpolebuildings.com/2012/08/ventilation-blows/.

Should I Buy This Building?

Some Unsuspecting Person Will Buy This Building (or one like it)

The post frame (pole barn) building industry is relatively unfettered by needs for buildings to have structural plan reviews (In My Humble Opinion [IMHO] BAD), building inspections (again IMHO – BAD), and plans sealed by a registered design professional (architect or engineer – again BAD).

This tends to lead to building owners who are less than satisfied with the outcome of their new buildings either blowing away or collapsing under the weight of less than expected snow falls.

The photo above is of a nice little horse loafing shed, advertised by a company from Alvin, Texas who not only provides post frame building packages, but also constructs them. The building in question is 13’ deep (wide) by 36 feet in length.

Again (IMHO) the true problem here is not with this company providing post frame building kits or constructing them – it is they are also prefabricators of light gauge metal connector plated wood trusses (they are a truss manufacturer). It is pretty much impossible to be a certified truss company, without building all trusses from drawings which are sealed by a registered professional engineer.

It is one thing for Chuck in a Truck to be ignorant of the importance of engineering, but for a truss company?

Get real.

This, to me, makes them culpable for foisting off on the public buildings which will most certainly not meet the Building Codes to which I say, “Shame on you”.

So why is it I would declare this building to not be Code conforming just from a little bitty photo?

The endwalls of this building have columns only at the corners – meaning the wall girts are spanning at least 12’1” between the columns. On the enclosed sidewall, the columns are every 12 feet, making the distance between columns slightly smaller (generally plan upon it being 11’6.5”).

Long time readers of mine have read my railing against wall girts which do not meet Code requirements, with this being probably my most persuasive piece: https://www.hansenpolebuildings.com/2012/03/girts/

From the article, a 12’ column spacing 2×6 wall girt, spaced 24 inches on center, with absolute minimal loading will deflect 3.226 inches, when the allowable is only 1.54”!!

This example building goes from bad to worse, as it is a three sided building which further multiplies the forces on the members! (read the horrors here: https://www.hansenpolebuildings.com/2014/03/three-sided-building/)

Even if the building would have been structurally adequate – which it isn’t, there is a lovely untreated piece of lumber across the open side of the building……again not Code conforming.

Moral of the story – if an engineer didn’t design it, who did?

Under-Designed Ag Buildings

Does Anyone Else See How This Could Be a Problem?

Eric, one of the owners of Hansen Pole Buildings, had me check out a website today for a pole building supplier who is extolling the virtues of a particular “nailed up” laminated column, which has been the subject of some discussion in my articles. https://www.hansenpolebuildings.com/blog/2014/04/titan-timbers/

This particular supplier took verbatim the information provided by the nailed up column suppliers, without questioning the validity of the data supplied.

Me, being the curious sort, took a cruise around the pole building supplier’s website.


“Snow Loading                                                                                   

Xxxxx Buildings commitment to quality is second to none. This is amplified by the fact that all buildings meet or exceed the MN State Building Code. Xxxxx Buildings provides all customers ‘peace of mind’ by making sure the roof system loading for your building will keep you protected from natures elements. The roof system loading includes the trusses and the roof purlins.”

Now I am all over this! I appreciate people with a commitment to high quality and excellence in pole buildings. “…all buildings meet or exceed the MN State Building Code” is way cool….

Hay Storage BuildingUntil I read their next paragraph:

“Ag Buildings
There is no code regulation of Ag buildings, (these buildings are exempt from the code) but suggested minimum loading would be 25 psf or 30 psf live load on the roof system. The definition of an Ag building would be a structure on agricultural land designed, constructed, and used to house farm implements, hay, grain, poultry, livestock, or other horticultural products. This structure shall not be a place of human habitation or a place of employment where agricultural products are processed, treated or packaged, nor shall it be a place used by the public.”

From one side of their mouths is “all buildings” meet Code, and out of the other – they are providing “ag buildings” with loads below Code!!

Here is the Minnesota State Snow Load map: https://www.dli.mn.gov/CCLD/PDF/bc_map_snowload.pdf

To get from a Pg (ground snow load), to a roof snow load, involves the multiplication by several factors. Learn more than you ever wanted to know here: https://www.hansenpolebuildings.com/blog/2012/02/snow-loads/

For discussion’s sake, we will assume these Ag buildings are unheated (most unoccupied buildings are) with the most common 4/12 roof slopes and steel roofing. The roof truss top chord live load under this combination should be 34.7 psf with 50 psf for Pg.

This provider’s, “suggested minimum loading would be 25 psf or 30 psf of live load on the roof system” is under designing these roofs to support snow by at least 13% and as much as 40%!!

You don’t own a farm, so what do you care?

When those under designed roofs collapse and the insurance companies pay to rebuild – it is YOUR insurance rates which are going to increase!

And if you do own a farm, I’d hate to be the one cleaning up the mess when your roof caves in…and hoping you are not in it when it does!