Tag Archives: closed cell insulation

Fire Rated Spray Foam Insulation

Spray foam insulation has become increasing popular for achieving high R value building shells. One downside of spray foams has been they are not being fire resistant.

I was pretty excited to read this on a post frame building contractor’s website:

“Installing foam insulation can either be sprayed or foamed-in-place. Foam has the ability to create an air barrier for the smallest of air leakages. Spray foam doesn’t retain water, providing excellent protection from the growth of mold and mildew. While foam insulation is generally more costly than other insulation options, it does have higher R-values and is fire rated.” 

As this particular contractor is a friend of mine, I dropped him back this question, “Spray foam insulation is fire rated?”

To this he replied, “Yes, some are, Tiger makes one.”

News to me, so I fired up my laptop and headed to Google, looking for more information.

Tiger Foam™ insulation (https://tigerfoam.com/sprayfoaminsulation/), according to their website, “is a proven leader in providing spray foam kits, supplies and accessories to homeowners and contractors alike.”

Again, according to their website, “We offer retails sales for small projects and wholesale, bulk pricing for bigger jobs. Our expert customer service team is always available to answer questions and help plan projects. Whether you’re trying to save money on your monthly energy bills or working to satisfy your customers. Tiger Foam can help. Most of all, our products provide high performance and great value. Become a customer today and get you the tools you need to start saving energy dollars!”

Well, sure enough, Tiger Foam™ offers a ‘Fast Rise’ kit providing a Class 1 Fire Rating. This fire rating means this building material is highly resistant to fire and does not spread flames quickly. Building materials with a Class 1 fire rating are often man-made or nonorganic substances. Other Class 1 building materials include brick, tile and cement.

I have never personally installed Tiger Foam™, however I have paid to have closed cell spray foam insulation installed by a professional installer. If you are considering using a closed cell spray foam for your new project, discuss fire rating with your installer of choice.

Reader Put Up a Competitor’s Shed

We Put Up a Competitor’s Shed

Sadly not everyone does adequate research to realize how outstanding of a value added a Hansen Pole Buildings’ post frame building kit package truly will be. Long time readers of these blog articles (nearly 1600) and questions answered in Monday’s “Ask the Pole Barn Guru™” column (around 1000) have come to understand most problems solved by me come from other people’s buildings.

How serious am I about our value:
I am offering to shop for you. Yes you heard me right. You give me up to three names of competitors to Hansen Buildings, where you can purchase a complete wood or steel framed pole building kit package, and I will shop them to get quotes for you.
Now I say three, because frankly, some people just are not very prompt or cooperative when it comes to getting back with price quotes.

Why would I do this? Comparing “apples to apples”, I know our price will beat theirs, every single time. I am doing this for your peace of mind. I guarantee other prices will be higher. And I will provide you with documentation to prove it!

There is a catch…..before I go shopping, you have to place your order for your new Hansen Pole Building kit….. subject to me “proving my point” by going shopping. Your payment to us will not be processed for ten calendar days. Within seven days of order, you’ll have competitive quotes in hand, or my documentation of having hounded them every week day for a week trying to get pricing for you (seriously, if you have to hound someone for a price, what kind of service will you get after they have your money?).

After I email you proof, if you seriously want to purchase from one of these competitors, just let me know before ten days from your investment and we tear everything up and go away friends.

Ask The Pole Barn GuruReader DAVE in ROBERTS apologizes for buying from a competitor and writes:
“Sir. Your blog has been most helpful. We put up a shed not one of yours but a competitor. (sorry). Shed size is 36×48. First mistake was we did not put a barrier under the concrete. Our plan now is R 19 in walls. One inch of foam plus R 39 in ceiling. I wired in two ceiling fans to move air with natural gas heat. Does this sound like a good formula, oh wise one?

Mike the Pole Barn Guru says:
Start by sealing your building’s concrete slab. This will be a possible solution: https://www.hansenpolebuildings.com/2018/11/siloxa-tek-8505-concrete-sealant/.

I am just not a fan of natural gas heat as it adds a tremendous volume of water vapor into your building. You’re going to have to find a way to exhaust all this water, else your building will have humidity issues.

Although now too late for you, there would have been alternatives: https://www.hansenpolebuildings.com/2016/12/modern-post-frame-buildings-geothermal/.

Let’s discuss your ceiling. I am hopeful you have trusses designed to support a ceiling load of five psf (pounds per square foot) or greater. Also hoping you have ventilation covered with enclosed vented eaves and a vented ridge. Unless you specifically asked for it, your building’s roof trusses probably do not have raised heels to allow for full insulation thickness above walls and in area closest to sidewalls.

Provided your trusses will support weight of gypsum wallboard, install any necessary framing to reduce drywall spans to two feet or less. Place 5/8” Type X sheetrock across bottom of ceiling framing. If you do not have a vapor barrier under your roof steel, spray two inches of closed cell foam insulation across the entire underside. Once you have paid for this, you will regret not having made other condensation prevention decisions.

While spraying foam – have it added to area closest to eave sidewalls (spraying onto top of ceiling drywall). Make certain to leave an inch of airspace minimum above foam, so air can flow in from eave vents. Foamed area should continue towards center of building until it reaches at least a six inch thickness. Balance of ceiling should have no less than R-45 and ideally R-60 of fiberglass insulation blown in.

For walls, I am hoping you have placed a Weather Resistant Barrier (WRB – like Tyvek) between framing and siding. If not, you have a couple of choices. You can remove wall steel from a wall, install a WRB and reinstall steel (repeat for each subsequent wall), or spray two inches of closed cell foam to inside of siding. Unless your building has full thickness bookshelf girts, install framing across inside of walls to eventually support wall finish (I recommend sheetrock). Fill entire insulation cavity with BIBs https://www.hansenpolebuildings.com/2011/11/bibs/.

Glue two inch thick closed cell rigid insulation panels to inside of wall framing, sealing all joints. Glue sheetrock to inside of insulation. Now you have a truly well insulated post frame building.

Blowing Attic Insulation

Blowing Attic Insulation, Without Vapor Barrier, Below Roof Steel

A very common problem I see involves people not preparing their post frame (pole barn) buildings to adequately be insulated.

Reader NED in THURMOND writes:

“Thank you for your help. I’m in process of completing a pole barn project. It’s divided into three sections…living area, workshop, and garage. The size is 24 x 44. The outside perimeter wall is 2×6 frame with OSB and metal on the bottom and metal only in the top portion. The wall cavity is filled with unfaced insulation and poly on the inside. The roof is 8’ oc trusses with metal panels and no moisture barrier. 6 mil poly was applied to the ceiling joists. I wanted to insulate the ceiling, so I removed the poly and plan to install Sheetrock and blow in R-38 overhead. The building has a ridge vent and soffit vents in the eaves. Do I need a moisture barrier on the ceiling or will the blown in insulation suffice? What, if any problems do you anticipate? Thank you so much.”


Mike the Pole Barn Guru responds:

Here are some anticipated problems –

Without some method of condensation control beneath your building’s roof steel you are going to have moisture problems. Blown in fiberglass or cellulose insulation will lose their effective R value once they get wet. A practical solution will be to have closed cell foam insulation sprayed upon roof steel underside. Normal recommendation would be two inches thick however your local applicator(s) can give you their best input from experience. Make sure spray foam does not block either eave air intakes or ridge exhaust points. You can create a “dam” at eaves to keep blown in insulation from filling soffits, by use of ripping high R closed cell insulation boards. Again, make sure not to block incoming airflow (you need a minimum of least one inch of free area above insulation boards).

Planning a new post frame building? If so, I encourage you to take appropriate steps for your building to have future insulation installed. Yes, there will be some initial investment involved.However it will be so much less expensive to plan for it now than to wish you would have later.

 

Insulating a Post Frame Building the Right Way

Insulation is the hot (pun, intended) topic. Everyone seems focused on energy efficiency in their post frame buildings. Reader CHRIS in TRAVERSE CITY got my head spinning on it once again:

“I recently purchased a property with a 24×30 pole building (metal siding, wood trusses and 3 tab shingle roof). I would like to insulate the walls and ceiling. I will likely remove the siding and add building wrap. I am most concerned with insulating the ceiling. The building will be used to store a tractor, Jeep and other toys. Plus I plan to use the building as a workshop and mancave. What are my options (cost is a factor but not critical)?”

I don’t know how old your pole building is, but if it is more than a year or two, you might as well plan upon replacing your roofing as three tab shingles just do not last. Look for cool metal roofing (https://www.hansenpolebuildings.com/2018/03/cool-metal-roofing/) as this will reduce your energy costs and may qualify for an income tax credit.

Back to the question at hand……my opinions on how to best insulate a post frame building have evolved over the years, so today’s advice is better than yesterday’s and tomorrow could be an entirely different story. All of this is predicated upon changing technologies.

Adding building wrap – good choice. Make sure it is well sealed, tape and seams or tears.

As your building is up, I’d look at adding an interior set of wall girts and then fill the cavity with BIBs (https://www.hansenpolebuildings.com/2011/11/bibs/ ). New construction would have different recommendations.

To super insulate your walls, apply two inch or thicker high R insulation sheeting to the inside of the girts. With taped seams, this also acts as a vapor barrier. Otherwise use 6 mil clear visqueen as a vapor barrier, before applying gypsum wallboard.

If you have enclosed vented soffits and a vented ridge, the next two paragraphs apply to your circumstance.

The biggest challenge for your ceiling will be if the trusses are designed to support the weight, if so then it is full steam ahead, if not, you will need to contact the truss manufacturer for an engineered repair to upgrade them.

Once you have drywalled the ceiling, you can blow in insulation to a depth appropriate for your area – a minimum of 15 inches thick, with 20 being even better. Chances are poor of your building having raised truss heels to allow for full insulation thickness as you approach the sidewalls. In this case, have closed cell spray foam insulation placed in the area closest to the walls, making sure to not impede the airflow from eave to ridge.

Without ventilation provided for, the easiest route is to use closed cell spray foam under the roof deck. As closed cell foam will give you about an R-7 per inch, you would need 6-1/2 to 8-1/2 inches to give adequate resistance to heat loss.

 

Spray Foam Insulation, Steel Roofing and Corrosion

Hansen Pole Buildings’ Designer Rachel recently had an interesting discussion with a client. The gist of the discussion was the client had heard spray foam insulation will corrode the steel and void the warranty of the steel.

Rachel did some research and found this article: https://www.greenhomeguide.com/askapro/question/can-i-apply-spray-foam-insulation-directly-to-the-underside-of-a-metal-roof.

When I added the external elevator shaft to the rear of our steel covered post frame home, my choice of insulation was closed cell spray foam. Although I knew it was going to be more expensive than other choices of insulation, I was (and remain) convinced of it being a superior R-value, as well as completely sealing the system. In the case of our addition, the steel roofing was applied directly over the wood roof purlins, without any solid sheathing or other barrier.

So, will spray foam insulation actually corrode the steel?

Highly unlikely, as from the research I have been doing there appear to be no chemicals in the spray foam which would react with the steel or the galvanized or galvalume protective layer over the bare material. Most steel roofing is factory finish painted, which adds yet another barrier surface in the interior primer paint coat which further isolates the steel from the spray foam.

There are some cases where I could see some challenges.

One would be if someone went on the cheap and used open cell spray foam, rather than closed cell. In this case moisture could get through the open cells and be in contact with the underside of the roof steel.

The other could occur if there was a leak in the roofing or the ridge cap which would allow moisture to get trapped between the roof steel and closed cell foam.

As to the warranty discussions – steel warranties primarily cover fade and chalking of the exterior finish of the steel. Personally I am hard pressed to see how it is the application of closed cell spray foam insulation on the interior of the steel roofing, would influence the life of coatings on the exterior.

Of course everyone looks for an “out” when it comes to warranties, and the reality is a good warranty protects the seller/manufacturer far more than it protects the consumer.

If I had it to do all over again, I would still closed cell spray foam my own steel roofed building. Check back with me in another thirty or forty years and see if my opinion is yet the same.

Spray Foam Advantages Over Batt Insulation

Once again – confession time. I’ve never personally used spray foam insulation.

My oldest stepson, Jake, teaches high school chemistry and physics. He is one smart dude, as he has a master’s degree. When he added onto what was formerly his grandparent’s home, in the Browns Valley, MN area, he utilized closed cell spray foam insulation.

Not only is Jake smart, but he is also frugal, which tells me he did his research and compared costs of not only the original installation, but also savings over time.

Polyurethane foam insulation is available in closed-cell and open-cell formulas. With closed-cell foam, the high-density cells are closed and filled with a gas which helps the foam expand to fill the spaces around it. Open-cell foam cells are not as dense and are filled with air, which gives the insulation a spongy texture.

Polyurethane and isocyanate foams are applied as a two-component mixture which comes together at the tip of a spray gun, and forms an expanding material. While open-cell foams typically have R-values of 3.5 per inch, closed-cell foams can attain R-values of 7 per inch. Closed-cell foam is very strong, and structurally reinforces the insulated surface. By contrast, open-cell foam is soft when cured, with little structural strength. However, it provides superior sound resistance and allows timber to breathe. It is also fire-resistant and won’t sustain a flame.

insulation-rollSpray foam insulation costs more than batt insulation, but it has higher R-values. It also forms an air barrier, which can eliminate some other weatherizing tasks, such as caulking. This plastic insulation goes on as a liquid and expands to fill the available space, sealing all gaps and cracks and stopping any air leaks (This can also keep out bugs or other vermin). Another advantage is foam can fill wall cavities in finished walls without tearing the walls apart (as required with batts). It also provides acoustical insulation and increases structural stability. When building a new post frame building, this type of insulation helps reduce construction time and the number of specialized contractors, which in turn saves money.

The cost can be high compared to traditional insulation; however, open cell foams provide a better economical ratio. Open-cell foam is $1 to $1.20 per sq. ft. while closed-cell foam is $1.75 to $3 per sq. ft. (for a 2-by-4-framed wall). Both require professional installation.

Here is an earlier example of the investments into each: https://www.hansenpolebuildings.com/2014/02/insulation-foam-fiberglass/

Although for moisture control closed-cell foam is non-porous, open-cell requires a vapor barrier; however, the added cost of closed-cell foam may not be as advantageous as vapor barriers are usually required by building codes, regardless of the type of insulation used. Also, closed-cell polyurethane insulation levels can drop over time as some of the low-conductivity gas escapes and air replaces it in a phenomenon known as thermal drift.

In summary, DIY people use fiberglass as it is readily available, maintains a reasonable price ratio and is easy to install. Although it is not as easy to sustain the higher performance required by today’s insulation standards over time. It is also a health hazard. Most tract homes also use fiberglass insulation for the same reasons. However, the installation experience of the contractors can improve the overall performance.

Higher-end tract homes and custom homes tend to use the cellulose and foam solutions. They provide a superior insulation level and a number of other advantages, including air and vapor blocking, noise reduction and insect minimization.

As with all things, you get what you pay for and you can pay up front or pay later. There is no shortcut to energy efficiency and saving money.

We will be adding an elevator shaft to our own post frame building home later this summer. Although it is not a large footprint area, it will be over 30 feet tall and keeping it the temperature of the rest of the building will be a high priority – so I will be investigating spray foam myself.