Tag Archives: setbacks

When Concrete Contractors Try to Act Like Engineers

Reader JEFFREY in CHARLOTTE writes:

“I want to build a woodworking shop next to my driveway that drops off sharply. I don’t have the space to add fill and slope away as it would put me over the setback on the neighbor’s property line. Local concrete contractor suggested a pole barn style would work best. He suggested I sink posts at the lower grade level 4′ deep at 4′ intervals and then add tongue and groove boards to essentially create a box that I could then backfill with gravel/sand compacting in 4″ lifts. Once that was done and the building was up then I could pour a slab on top of that inside the building. I estimate the grade difference to be roughly 4′ from the driveway to the lowest point where the back wall of the building would be. My building size would be 24′ long and 22′ wide and I want an upper gable room for storage. I would like to be able to stand up inside the “attic”. What do you think of this proposal? To have foundations and poured walls put in would blow me way out of my budget.”

This is why concrete contractors are not allowed to engineer buildings (unless they have actually gone to school, passed their boards and gotten registered). As suggested, a large load is going to be placed upon your building’s columns along this wall, resulting possibly in larger columns, greater embedment depth and more concrete around columns. Throw in what you will invest in two sets of four foot high UC-4B pressure preservative treated tongue and groove lumber and you are talking some serious money.

I am always into looking for simple and affordable solutions. To me, building a concrete block retaining wall along my property line would seemingly be an excellent alternative and would not involve having to pay an engineer to design it. You could then bring in compactable fill to get to level and happily build away.

As far as your attic “storage” idea, be wary. By Building Code, light storage areas need to be designed for a 125 psf (pounds per square foot) live load. Even on a 22 foot truss span, these trusses are going to be expensive. Now you could designate this as a ‘bonus room’ and provided your Building Department buys into it, you could have a much lower live load (as little as 30 psf). You would need to remain mindful of what you were actually placing in this area, so as not to overload it and cause an unintended failure.

You will also have to deal with access. While pull down stairs are convenient they provide a very limited opening to get things into this bonus room space. Permanent stairs must be at least three feet in width and meet maximum rise and minimum run standards as well as headroom and clear space at top and bottom of run considerations. When all is said and done, they would chew up a lot of your woodworking space.

Looking for a Place for a New Barndominium

Looking for a Place for a New Barndominium

Reader PATTI in MINNESOTA writes:

My husband and I are knocking around the idea of doing a Barndominium. 

We need a 4-5 car garage space and we can barely afford a traditional preloved home that has a 3-car garage which will require us to add another stall or two onto an already taxing home price!

I’m optimistic that we can pull off everything that’s needed and hopefully within the budget!

I’m doing the bulk of the research and found your site to be so packed with worthwhile information.  I want to see what you’d be able to do for us to make this as seamless and headache free as possible?

I started looking for property and messaged the City Halls for the locations we want to see if they’d allow such a structure.  Not sure how to handle the siding issue.

Inver Grove Heights, MN 

Will consider it a single family home.  Needs to meet setback, height and doesn’t exceed allowed impervious surface for the lot.  

Exterior siding regulations require horizontal lap type siding or similar.  Vertical siding like a pole barn is not acceptable material.  

**** Is this even possible to meet this request or is there a way we can argue against it.  Any knowledge you can offer would be so helpful****

Rosemount, MN

“The structure would function as a single family home, and therefore the exterior materials would need to be complementary to a residential structure (no metal siding, etc.).  Additionally, the foundation would need to meet the building code requirements for frost footings.  Also, the zoning code regulates the size of attached garages as follows: The footprint of an attached garage is a maximum of 1,000 square feet but can be increased up to a maximum of 1,500 square feet so long as the garage does not exceed 50 percent of the gross floor area of the principal building (garage and living area combined).”

Farmington, MN

*Considers this Agricultural that would need a minimum of 40 acres, what!!!

****Is this common and is there anything we can do to fight this so we get this under a single family home that we could put on a .25 acre plot?****”

Mike the Pole Barn Guru responds:

Thank you for reaching out to us and for your kind words.

Planning Departments are an extension of a jurisdiction’s ruling body (city council, county commissioners) and have basically power of life and death. They can dictate footprints, heights, setbacks, type of cladding (roofing and/or siding), and even colors. They ARE limited to ordinances written by their ruling body, so if you do not hear an answer you like, ask for a copy of their written ordinance. If they cannot produce one, then it does not exist and can be disregarded.

One beauty of fully engineered post frame construction is a broad variety of siding and/or roofing options are readily available.

Inver Grove Heights – exterior siding is within their realm of control.  At www ighmn.gov go to “City Code” in the left hand menu list and click on it. Scroll down to Chapter 15, then 10-15-17. B.2 gives your options with steel being none of them.

Rosemont – you do not have to pour a concrete foundation to meet Code requirements for frost. You will have to insulate the perimeter of your building to at least four feet below grade, not a big deal and can be done with rigid insulation (this insulation is typical for any type of structure). If you erect a 3000 square foot (sft) building, as much as 1500 sft can be garage.

Farmington – you threw them off at “pole barn house”. You are building a fully engineered custom designed wood frame home. This should be allowable anywhere zoned for single family residences. You may have exterior appearance and footprint issues once they have gotten this into their heads as being a SFR (Single Family Residence).

You will find as you get farther away from Minneapolis and into county rather than city controlled areas, things tend to become more property owner friendly. You also might consider South Dakota as an option, as our Planning and Zoning restrictions are few and far between.

Zero Lot Line Post Frame Construction

There are occasions where the best location to place a building just happens to be right up to a lot line. Let’s face realities – if your site’s required setbacks without fire resistive construction are five feet, what is going to accumulate in this area? Most often it is either “stuff” or weeds, neither of these being aesthetically pleasing.

Reader CLINT in SPOKANE, is faced with this and writes:

“I have a unique question regarding a firewall.  In Spokane County you are allowed to build up to the property line of your neighbor given that you have a 1hr rated fire wall from both sides on the property line.  (2hrs total).  I’ll attach a copy to the code requirements.  To meet code apparently you have to use “type x” drywall on both the interior and exterior of the wall.  I understand the install and have even read up on your reference to a 3hr firewall from some time ago.  My question is, how do you weather-proof the exterior drywall? It seems that putting metal siding directly over-top the drywall could lead to moisture damage.  I’m guessing that even if it is OK for most of the wall what about the lower ground level part?  Do you need a vapor barrier or special trim/flashing to prevent splash damage from ground level. Or maybe even humidity alone could be bad?  I’ve seen what drywall does with water so that is my concern with it being only a metal layer away from the elements. Thanks for your help!”

Mike the Pole Barn Guru advises:

While your copy of Spokane County’s requirements did not make it, I am fairly familiar with them as I was once their most prolific post frame building contractor (built over 200 buildings in Spokane County in a single year).

To reach two hours, you should have two layers of 5/8″ Type X on each side of your framed wall. You also need to insure any rain or snow coming off your roof does not land in your neighbor’s yard. This will entail a slight setback to allow for gutters and you will need a snow retention system on this side of your roof (this is assuming we are discussing an eave side and not an endwall).

Start with investing in “green board” 5/8″ Type X drywall. While not waterproof, it is moisture-resistant. It is available from providers such as GTS Interior Supply in Spokane. You should use a Weather Resistant Barrier (WRB) on your exterior between drywall and steel siding. Screws for steel should be three inches in length for this wall, in order to get adequate penetration into wall girts. Base trim (aka rat guard) can be special ordered with a longer flat leg to seal off water splash up from ground. Mineral (rock) wool insulation should be used in this wall, as it is not affected by moisture.

Extended reading about NFBA’s three hour firewall testing can be found at https://www.hansenpolebuildings.com/2012/03/firewall/

Building Department Checklist Part I

BUILDING DEPARTMENT CHECKLIST 2020 PART I

I Can Build, I Can Build!

Whoa there Nellie…..before getting all carried away, there are 14 essential questions to have on your Building Department Checklist, in order to ensure structural portions of your new building process goes off without a hitch.  I will cover the first seven today, finishing up tomorrow, so you have a chance to take notes, start your own home file folder of “what to do before I build”.  Careful preparation will be key to having a successful building outcome (whether post frame or some other structural building system).

Provide answers to these questions to your potential building providers!

IMPORTANT SIDE NOTE: Building Departments’ required snow and wind loads are absolute minimums in an attempt to prevent loss of life during extreme events. They are not established to prevent your building from being destroyed. Consider asking your providers for added investment required to increase wind and/or snow loads beyond these minimums.

#1 What are required setbacks from streets, property lines, existing structures, septic systems, etc.?

Seemingly every jurisdiction has its own set of rules when it comes to setbacks. Want to build closer to a property line or existing structure than distance given? Ask about firewalls. If your building includes a firewall, you can often build closer to a property line. Creating an unusable space between your new building and a property line isn’t very practical. Being able to minimize this space could easily offset a small firewall investment. As far as my experience, you cannot dump weather (rain or snow) off a roof onto any neighbor’s lot, or into an alleyway – so keep those factors in mind.

#2 What Building Code will be applicable to this building?

Code is Code, right? Except when it has a “residential” and also has a “building” version and they do not entirely agree with each other.

Also, every three years Building Codes get a rewrite. One might not think there should be many changes. Surprise! With new research even things seemingly as simple as how snow loads are applied to roofs…changes. Obviously important to know what Code version (e.g. 2012, 2015, 2018, 2021) will be used.

 

#3 If building will be in snow country, what is GROUND snow load (abbreviated as Pg)?

Make sure you are clear in asking this question specific to “ground”. When you get to #4, you will see why.  Too many times we’ve had clients who asked their building official what their “snow load” will be, and B.O. (Building Official) replied using whichever value they are used to quoting.  Lost in communication was being specific about “ground” or “roof” snow load.

As well, what snow exposure factor (Ce) applies where a building will be located? Put simply, will the roof be fully exposed to wind from all directions, partially exposed to wind, or sheltered by being located tight in among conifer trees qualifying as obstructions? Right now will be a good time to stand at your proposed building site and take pictures in all four directions, and then getting your B.O. to give their determination of snow exposure factor, based upon these photos.

#4 What is Flat Roof Snow Load (Pf)?

Since 2000, Building Codes are written with flat roof snow load being calculated from ground snow load. Design snow load has become quite a science, taking into account a myriad of variables to arrive with a specific roof load for any given set of circumstances.

Unfortunately, some Building Departments have yet to come to grips with this, so they mandate use of a specified flat roof snow load, ignoring laws of physics.

Make certain to clearly understand information provided by your Building Department in regards to snow loads. Failure to do so could result in an expensive lesson.

#5 What is “Ultimate Design” or Vult wind speed in miles per hour?

Lowest possible Vult wind speed (100 miles per hour) only applies in three possible states – California, Oregon and Washington for Risk Category I structures. Everywhere else has a minimum of 105 mph.  Highest United States requirement of 200 mph for Risk Category III and IV buildings comes along portions of Florida’s coastline (although there are scattered areas nationally defined as “Special Wind Regions).  Don’t assume a friend of yours who lives in your same city has your same wind speed.  City of Tacoma, WA has six different wind speeds within city limits!

Vult and nominal design wind speed (Vasd) are different and an errant choice could result in significant under design (or failure). Make certain to always get Vult values.

#6 What is wind exposure (B, C or D)?

Please Take a few minutes to understand their differences:

(https://www.hansenpolebuildings.com/2012/03/wind-exposure-confusion/).

A Building Department can add hundreds, or even thousands, of dollars to your project cost, by trying to mandate an excessive wind exposure.  Once again, a good place for photographs in all four directions from your building site being shared with your Building Department.  Some jurisdictions “assume” worst case scenarios.  Meaning, your property could very well have all four sides protected and easily “fit” category B wind exposure requirements.  However, your jurisdiction may have their own requirement for every site in their jurisdiction to be wind exposure C, no matter what.  It’s their call.

#7 Are “wind rated” overhead doors required?

Usually this requirements enforcement occurs in hurricane regions. My personal opinion – if buying an overhead door, invest a few extra dollars to get one rated for design wind speeds where your building will be constructed. Truly a “better safe, than sorry” type situation.

I’ve covered seven most important questions for your Building Department Checklist, and they really weren’t so difficult, were they?  Come back tomorrow to find out the last seven!