Tag Archives: rake trim

Knee Bracing, Flying Gable Trim, and Ventilation Needs

This week the Pole Barn Guru answers reader questions about the removal of knee bracing to install interior ceiling and wall steel, a question about a special rake trim for a flying gable, and the possibility of adding ceiling liner panels to a structure and the need for a vapor barrier and proper ventilation.

Pole Barn Knee BracesDEAR POLE BARN GURU: Can I remove my knee bracing from the pole barn and put up interior ceiling and wall steel. I have a 60×104 pole barn on an 8″ wide 4′ high concrete wall with wet set braces (6×6 laminated beams. 8′ on center) ceiling is 16′ from floor my knee bracing takes up too much wall storage space. They brought them too far down the wall. About 6′. SEAN in MONTPELIER

DEAR SEAN: While knee braces generally cause far more structural harm, than good, they should never be removed without written authorization from whomever your building’s engineer is. If your building was not engineered (hopefully it was), then you should at least request written authorization from your provider including verification their removal will not affect any structural warranty.

In this article, another person dealt with similar issues: https://www.hansenpolebuildings.com/2015/11/can-i-take-out-knee-braces/


DEAR POLE BARN GURU: How do I trim out a metal ribbed roof panel on a barn with a widows peak? How do I make it match up with the rake trim? While maintaining proper drainage. KEVIN in LINCOLN

DEAR KEVIN: Your building kit provider should have had delivered to you one or more ‘special’ rake trims (one long side like a standard rake/corner trim, other flat with a hem) and some Emseal expanding closures. Here are your installation instructions: https://www.hansenpolebuildings.com/2016/05/9-steps-constructing-widows-peak/


DEAR POLE BARN GURU: I have a pole barn with a scissor truss (interior sloped ceiling) at 8′ on center. The builder placed insulation between the trusses and are kept from sagging by perpendicular metal straps approximately 2′ apart. When the breeze blows into the shop, the insulation batts float up and down like waves. I was thinking of installing a metal ceiling. I am concerned about the 8′ span between trusses and the possible need for a vapor barrier. What do you recommend? GREG in HUDSON

vented-closure-stripDEAR GREG: Hopefully you have vented eave soffits and ridge cap in correct ratios as lack of ventilation or too much or too little in wrong places can cause challenges (please read more here: https://www.hansenpolebuildings.com/2018/03/adequate-eave-ridge-ventilation/).

In your Climate Zone a ceiling vapor barrier should prove unnecessary. While I would not span eight feet with ceiling liner panels, I do see it being done successfully by many builders and specifiers.


Gable Rake Trim, 24″ oc Framing, and Lap Siding Options

Today the Pole Barn Guru answers questions about cutting the rake trim at the gable end, Mike’s thoughts on 24″ oc framing for drywall, and types of lap siding options.

DEAR POLE BARN GURU: Can you advise me on how to cut sculpted rake trim at gable.  Pitch is 4/12.  This trim is a little hard to work with due to the angles that I suppose give it the name “sculpted.  Wanting to overlap the two pieces. 

Thanks, HEATH

DEAR HEATH: This excerpt from Hansen Pole Buildings’ Construction Manual should assist you:

At peak, See Figure 22-5 (when I piece ‘folds’ over peak) or Figure 22-6

Figure 22-5: Gable Trim @ Peak Cutting


Interior Wall FramingDEAR POLE BARN GURU: With lumber prices being what they are, what is your take on doing all interior framing on 24 inch centers and using all 5/8 drywall everywhere? Do you feel like it would be a significant enough savings to warrant it. I know that builders typically struggle with achieving dead flat walls even with 16 inch center framing. I’m willing to invest the time in choosing my framing materials to minimize the potential for waves. I guess it really just boils down to being able to accept slight imperfections in the wall in order to keep the project affordable. I’ll invite any opinions on this as long as it’s civil. RUSS in PIPERSVILLE


DEAR RUSS: I am a huge fan of using 5/8″ Type X drywall everywhere. In fact, I used it in our own shouse (shop/house). It offers several advantages, besides just an increase in fire protection. Its added stiffness hides a plethora of framing imperfections and it tends to lay smooth over framing two foot on center. We have found it to be very durable in holding up to my paraplegic wife’s power chair (yes, collisions do occur). Another often overlooked virtue – it dampens sound transmission through walls. For a couple of cents per square foot of material in my humble opinion it is a no brainer.


DEAR POLE BARN GURU: Do you have a siding option that resembles vinyl lap siding? CHUCK in HOGANSVILLE

DEAR CHUCK: We can provide an exact match – vinyl lap! https://www.hansenpolebuildings.com/2017/06/vinyl-siding-pole-barns/


Planning Building Dimensions Around Width of Steel Panels

Reader JON in KENNEWICK is working on planning for his new post frame building and writes:

“My question is regarding the size of the steel wall panels. I was watching a pole barn building video on YouTube and the builder, RR Buildings, was talking about sizing the building to correspond with the size of the wall panels. His example was a 120′ long building and using 3′ wide wall panels. Since the building length was evenly divisible by the width of the panels, it would save work due to less cutting. A 120′ building would take 40 full width 3′ panels. Seems to make sense to me but I’m a Noob to all of this and think I might be missing something. Your opinion? Since I am in the planning stages for my building should I take this into consideration? Is 3′ the industry standard for wall panels?

I’d appreciate any input you have. I’m a Nervous Nelly and want to get my building right the first time around.”

Mike the Pole Barn Guru responds:

Nearly all through-screwed structural steel roofing and siding panels are manufactured for a three foot net coverage. Each panel has an underlap and an overlap, so you should account for this and ideally go with measurements from outside of column to outside of column in multiples of three. Once framing is added your framed footprint dimensions will increase in length and width by three inches. Begin the first panel on any given corner at 3/4″ past corner column and you will end up when you reach the far end of the wall not having to rip a sheet of steel lengthwise. Plan roof overhangs similarly – if you have eave side walls in a multiple of three, 18 inch overhangs on each end will continue this ease of installation. Besides being quicker and easier to install, it also places a high rib of steel under each corner and rake trim, helping to avoid unintended leaks.

Not every engineer or supplier plans their buildings so carefully – so you will want to verify with any provider how they do measure their buildings.

As to how to best plan the size of your building – ignore what I have just told you and work from building insides outward. Fit everything you want in and then build a box around your functional spaces. Yes, you might end up having to rip a sheet of steel, or several, but it is not impossible.

How to Install a Steel Roof Over Shingles

How to Install a Steel Roof Over Shingles
Absolutely true story, with me as part of it! My lovely bride bought a raw weed covered property along the South Dakota shore of Lake Traverse in the early 1990’s. For a home, she had a double wide manufactured home set up on the property. A few years later, she had a 32 foot square stud framed garage added. Both the home and the garage had asphalt shingle roofing.
Between extreme temperatures from 100 F plus in summer to -40 F., some potent winds and occasional hail storms, this is a brutal climate for shingles. More than a few of them had broken or blown off.
Reader DAN from MOUNDS VIEW triggered this soliloquy with his message to me:
“I was reading past questions and the subject of metal roofs was brought up, which prompts this question.

We have a cabin that I intended to have a metal roof but didn’t get one. We are now getting close to needing a re-roof and I’d like to get metal on it.

The question is, when starting with an existing asphalt shingle roof, installed over, I believe 1/2 cdx, what should be done to prepare for the metal? FWIW, it’s a 10/12 pitch.


Mike’s story:
Before sharing what we did I did my usual Google search to see if I could find someone else’s good advice. Ran across some scary stuff, so I felt compelled to share.

steel roofingMy wife’s roof had only a single layer of shingles. If I had more than a single layer I would scrape them off as it would potentially overload your roof trusses or rafters.
We placed 2×4 flat on top of the shingles running the long direction of the roof and 24 inches on center. Allowable spacing will vary due to snow load where the building is and load capacity of the steel. You are going to hear (actually read) me tell you I would do it differently soon. We used 40d threaded hardened nails to attach the nailers – with two nails through the nailer into the top chord of each truss. The nail length (five inches) is enough to get into the trusses comfortably with the threads helping to resist wind uplift issues.

A1V radiant reflective barrier was placed draped loosely over the nailers and the steel installed with 1-1/2” long powder coated diaphragm screws.

Here is what I would do differently next time. I’d run a 1×4 nailer up the roof on top of each roof truss., then the 2×4 nailers. This would allow for free airflow up the roof for eave to vented ridge.

For trims, use an eave trim at the low edge along the sidewalls. Install on top of 2×4 nailer at edge of overhang leaving the vertical about an inch out from the fascia. Place one inch thick venting material between the vertical leg of the eave trim and the fascia to keep insects out. Standard Rake trim and Ridge Cap can be used, with vented closure strips beneath the ridge cap.

It’s been about eight years since we reroofed my wife’s house and garage with steel and it still looks brand new.

Perfect Pitch, Added Expense, and Endwall Roof Leak!

DEAR POLE BARN GURU: Could you tell me the pitch of the roof…for small pole barn…..front wall is 10 foot high…back wall is 8 foot high…rafter span is 13 feet. HERBERT in HAMPTON

DEAR HERBERT: Roof slopes are expressed as the number of inches of rise per 12 inches of run. 24 inches of rise in 13 feet of run would be a slope of 1.846/12 or 8.745 degrees. Some cautions – if you intend to use steel roofing, chances are excellent the paint warranty will be voided due to a roof slope of under 3/12. The side laps of each panel should also have strip mastic placed on top of the under laps to assist in preventing leaks. This slope is also too flat for shingles, unless special considerations have been made for underlayments (most Building Departments require 90# felt paper or an equivalent). I’d recommend you increase the roof slope to 3/12 or greater.


DEAR POLE BARN GURU: Can I order specific species with my kit? I’d prefer Doug fir for all the wood, including PT.

Can I choose heavier gauge steel panel for roofing and siding than 29 gauge?


changeDEAR JEFF: You can specify a specific species, however be prepared to pay a premium for doing so, especially in the case of the pressure treated wood. Douglas Fir does not take pressure treating well, so only a few limited chemical formulations are available which will work with it – some of which happen to be highly corrosive to steel. This results in having to place a barrier between the treated lumber and the steel siding, as well as the use of heavily galvanized or stainless steel fasteners.

Most roof truss manufacturers will not guarantee a specific species of lumber will be used in their trusses – so this could become problematic, in your case.

Please read more about lumber species choices here: https://www.hansenpolebuildings.com/2012/03/lumber-species/ (please note this article was written prior to the design values for Southern Pine being reduced).

You may also choose heavier gauge steel panels, however you should read this article first: https://www.hansenpolebuildings.com/2012/01/steel-thickness/


DEAR POLE BARN GURU: We built a 30 x50 pole barn with 2 10 ft attached sheds about 1 1/2 years ago. It has sprayed foam insulation and finished inside with sheet-rock. Our problem is every time it rains hard it leaks at the corners on one end. Any suggestions of what we could do to try and find the leak? Thank you so very much for any information you could give us. MARK in SASAKWA

DEAR MARK: I am going to take a WAG (Wild Guess) here. The guess is actually probably not overly wild, since you are telling me the leaks only occur at one end of the building and happen on both sides of the roof.

Your building is 50 feet in length, which means it took 16-2/3 sheets of three foot wide roof steel to cover each side of the roof. This is with the assumption your building has no endwall overhangs. This also means the last sheet of roof steel on one end had to be ripped lengthwise to remove the extra foot of steel. When the rake trim was then installed, there was not a high rib of steel under the trim. When it rains (or snow falls on the roof and melts) water seeps under the edge of the rake trim and into your building. If indeed this is the case, the rake trims on the offending end can be unscrewed, and strip mastic can be used between the edge of the rake trim and the roof steel to keep the water from going where it is not intended to be – screw the rake trim back into place and all should be good once again!

Let me know if this is not the case and we can look for other solutions.