Home >> reflective insulation

Tag Archives: reflective insulation

Decisions, Decisions – Vapor Barrier for a Post Frame Steel Reroof

Decisions, Decisions – Vapor Barrier for a Post Frame Steel Reroof

There are few reasons to replace an existing post frame building’s steel roof, as properly installed it should last a lifetime. Among these reasons could be:

Tired of Existing Color
Old roofing was nailed on
Tree fell through roof

This last one actually occurred to our shouse (shop/house) when I lived in Northeast Washington!

Loyal reader and Hansen Pole Buildings’ client MIKE in COUPEVILLE writes:

Reflective Insulation“I am currently re-siding/re-roofing an existing pole building in order to match the exterior of the building I recently purchased from you.  This building is roughly 32 x34 and the roof purlins are 2×6 on end roughly every 2 feet.  I’m using Fabral’s grand rib 3 29ga for the roof and it will have fully vented soffit overhangs and a vented ridge cap.  I am trying to figure out what I’m going to do for at least a vapor barrier under the roof steel, I see you seem to recommend foil faced bubble insulation but that is not very common in my area.  I am seeing a lot of people using lamtec wmp-vrr (fiberglass insulation with a poly backing)  3″ thick and I believe they lay these wide rolls on top of the purlins and then place the metal roofing on top of that then screw down the roofing compressing the fiberglass insulation between the metal roofing and the purlins.  Have you seen this style of insulating before?  Do you think it is an acceptable way of doing it?  I see as killing two birds with one stone.  I may be insulating this shop in the future so if I do then the roof is already insulated plus I believe it acts as a vapor barrier which is the main reason to do it as I don’t want any condensation dripping down on the inside of the shop.  I live in the Seattle area if that helps to know what my climate is like.  Thanks in advance for your input.” 


Mike the Pole Barn Guru responds:

Our recommendation would be to order your roof steel with factory applied I.C.C. (https://www.hansenpolebuildings.com/2020/09/integral-condensation-control-2/).

Metal Building Insulation (fiberglass with a vinyl facing) is a decent condensation control, provided all of the seams are tightly sealed. It is a pain to work with, provides very little effective insulation value and makes your roofing pucker outwards between purlins https://www.hansenpolebuildings.com/2011/11/metal-building-insulation-in-pole-buildings-part-i/.

If it is too late for an I.C.C. then the radiant reflective barrier (https://www.hansenpolebuildings.com/2017/05/effective-reflective-insulation/)

 is probably your best option.  Order in six foot width rolls to minimize seams and make sure to get a product including a tab along one edge with an adhesive pull strip attached.

This entry was posted in Insulation, Pole Barn Questions, Roofing Materials, Pole Barn Planning, Steel Roofing & Siding and tagged , , , , , , , on by .

Rick’s Cabin Dominium

Rick’s Cabin-dominium

Many of you loyal readers have followed Rick Carr’s journey towards having a finished post frame cabin-dominium.

For those of you who have missed out, here are earlier articles chronicling his progress:

https://www.hansenpolebuildings.com/2019/03/development-of-my-cabin-plans/

https://www.hansenpolebuildings.com/2019/03/participating-in-ricks-post-frame-cabin-planning/

Rick’s project caught some eyes beyond our everyday readership. Editors of “Garage-Carport-Shed Builder” magazine became enamored of Rick and featured him on Page 27 of their Summer 2020 edition.


Rather than me blather on, please enjoy at this link:

https://s22327.pcdn.co/wp-content/uploads/GCS-Builder_Summer2020.pdf

This entry was posted in Uncategorized and tagged , , , , , , on by .

Ganged Wood Trusses & Closed Cell Spray Foam Post Frame Condensation Control

Ganged Wood Trusses and Closed Cell Spray Foam Post Frame Condensation Control

Ganged wood trusses are most usually two individually fabricated metal connector plated roof trusses, fastened together with either nails or even better Simpson Drive Screws (https://www.hansenpolebuildings.com/2017/03/simpson-drive-screws/), so they work together as a conjoined pair.

True doubled trusses (not two single trusses spaced apart by blocking) afford many structural advantages (https://www.hansenpolebuildings.com/2018/09/true-double-trusses/). However if closed cell spray foam is being used to control condensation underneath steel roofing, a little extra prevention is worth a pound (or two) of cure.

Most often conditioned post frame buildings are designed around having a flat (or slightly sloped using scissor trusses) ceiling. Warm moist air from this conditioned space rises into building’s attic and hopefully has a place to go. Most generally best design solution involves venting this dead attic space. Appropriate amounts of air intake provided by eave soffit vents and air exhaust utilizing a vented ridge will eliminate most moisture.

As those of us who did not nap during science classes are aware – warm air rises. Some of this warm air will get trapped below roof purlins or other attic framing members and not exhaust as imagined.

There are many methods of controlling or eliminating this warm and moist air from coming into contact with cooler roof steel. Least expensive (although potentially labor intensive if windy) would be a reflective radiant barrier (https://www.hansenpolebuildings.com/2017/05/effective-reflective-insulation/). One step up in investment, but very easily installed, would be an Integral Condensation Control (https://www.hansenpolebuildings.com/2017/03/integral-condensation-control/).

Some folks opt to sheath over trusses and roof purlins with OSB (Oriented Strand Board) or plywood, with 30# asphalt impregnated paper (roofing felt) placed between sheathing and roof steel. This can tend to run up one’s investment, as not only will more material and labor be directly involved, but trusses also must be appropriately designed for added weight carrying ability.

Enter closed cell spray foam. Long time readers have grown tired of me solving condensation challenges by people who did participate in one of these solutions and are now faced with a drip-drip-drip. Two inches of closed cell spray foam applied beneath a steel roof between purlins and trusses will create an almost entirely effective thermal break and take care of nearly all condensation issues.

Except…..
Metal connector plates trusses have pressed steel plates on each side. These plates project slightly from lumber faces and when two trusses are joined together, some gaps will occur between them. Gaps wide enough to allow for a significant flow of warm moist air to reach your roof steel, condense and start wreaking havoc.

There is, however, a simple fix, easily done during building framing. Before conjoining two or more trusses, place enough urethane or acoustic caulking between top cords to provide a complete air seal when in service!

This entry was posted in Insulation, Post Frame Home, Roofing Materials, Pole Barn Planning, Pole Barn Structure, Barndominium, Ventilation, Building Interior, Pole Barn Homes and tagged , , , , , , , on by .

Barndominium: Building Kit or Building Shell?

Barndominium: Building Kit or Building Shell?

This was a recent post from a Barndominium discussion group I am a member of:

“Kit vs shell; I’m defining a kits as coming with everything like insulation and metal studs (the next step would be mechanical trades) whereas shell would be dried in with nothing. Kit companies would accept owner floorplans or have some stock floor plans and provide CAD to guide builders. Shells would perhaps provide instructions or rely on the knowledge of builders. Kits would have customer service and a modern web site; respond to emails and be familiar with barndominiums. Shells would be a business that sells barns and commercial buildings, expecting owners to know what they want. Kit metal and studs would be pre-cut in the factory. All window openings would be accounted for. Shells would be metal has to be cut on site. Shell would be all decisions are made before building begins via email; drawings back and forth. Shell would be last minutes decisions during building. Are these definitions even close to being accurate? If not what are the industry definitions? By my definition, I’m looking for a kit, not a shell. If kit is not the right word, what is the correct term? What are the top ten companies that provide what I call a kit? In this Barndo group, there are clearly differences in skill and knowledge levels. Recently on this site, a vendor posted a shell drawing and price. Some people posted questions that indicated they wanted to shop for what I call a kit; there was some misunderstanding, I think. It would be helpful to me, and perhaps others if these concepts were defined, I think. Please point out the fallacies in my thinking, if any, before I move from drawing floor plans into shopping for kits/shells.”

Mike the Pole Barn Guru’s response:

About Hansen BuildingsWe provide custom designed engineered post frame building kit packages. As we are wood framing, we provide no metal studs. We can supply Weather Resistant Barriers and Reflective Radiant Barriers as well as batt insulation. We typically provide only structural portions of buildings – exterior shell, any raised floors (for crawl spaces, second or third floors or lofts) but can provide interior wall framing, if desired. We can work from any client supplied floor plans, elevation drawings or sketches. We do not have ‘stock’ plans, as every client’s needs are different. We expect our clients to layout their own interior rooms, to best fit with those needs and lifestyle.

We provide complete 24″ x 36″ blueprints for permit and construction sealed by third-party engineers, with full calculations. All openings, including windows are located on plans. There should be no “last minute” decisions made whilst building.

Our comprehensive (nearly 500 page) construction manual is designed for an average literate person to successfully assemble their own beautiful building, without requiring a contractor. We provide unlimited free technical support. Clients have an online portal to track progress and deliveries, etc.

Steel roofed and sided buildings come with cut to length steel panels, however some cutting will be needed in the event of oddly located openings or width and lengths of buildings other than a multiple of three feet.

At the risk of sounding redundant (I’m a proud owner of a “shouse”) go back to yesterday’s blog to see a picture of my and my wife’s shouse or barndominium.

If a post frame building is on your radar, then we are going to be #1, call us today 1(866)200-9657.

This entry was posted in Professional Engineer, Lofts, Pole Barn Questions, Pole Barn Homes, Pole Barn Design, About The Pole Barn Guru, Post Frame Home, Pole Barn Planning, Barndominium and tagged , , , , , , , on by .

Reduce Heat, Garage Kits, and Updates to Aging Building

Reduce Heat, Garage Kits, and Updates to Aging Building

DEAR POLE BARN GURU: I’m looking to build a 40×48 monitor style barn with a 16×48 loft in the center. I don’t plan to heat or cool the loft but would like to reduce the heat in the summer. My first plan is to use a light color or Galvalume for roof metal. My second idea and where I need more advice is on insulating the roof. I was thinking about first laying down foam board insulation and then putting metal roof down. I’m sure there are issues with this option please help me out. I also want to use the insulation to help deaden the sound when it’s raining. MICHAEL in ENTERPRISE

Wood Horse BarnDEAR MICHAEL: Many different colors of “cool roof” steel are now available, which adds far more flexibility in aesthetics – one is no longer limited to bare Galvalume or galvanized, or white- https://www.hansenpolebuildings.com/selecting-building-colors/
Foam board insulation between the roof purlins and the steel roofing would be one of the worst possible choices you could make, from a structural standpoint. It allows for the roof screws to flex within the thickness of the insulation, creating leaks and reducing the strength of the roof steel to resist wind shear. Some other options would range from installing a radiant reflective barrier under the roof steel, or (better yet, although more expensive) using closed cell spray foam insulation.

DEAR POLE BARN GURU: Hello, I am interested in one of the garage kits I found on The Home Depot’s website. I would like to see floor plans and interior dimensions for this kit. And what size would a cement pad need to be to fit under this structure? 48ftx60ft? Hope to hear back soon. Thank you! DAYNA in EAST TEXAS

DEAR DAYNA: The beauty of post frame buildings is a concrete slab is not required in order to support the building. As to floor plans – unless otherwise requested by a client, most post frame buildings are clearspan structures, without any interior columns or partitions. This allows for the total flexibility to place walls wherever one chooses, if any. The quickest way to hear back soon is to include an email address to send responses to.

 

DEAR POLE BARN GURU: Hello. We are starting to look into getting some new insulation and facing put in our shop. The current product is at least 15-20 years old. We were going to just carefully wipe down the dirty putter facing and postpone this project for another year or two, but that job in itself quickly became a hassle. As we are currently looking into which insulation and facing we will replace it with, we are trying to figure out what kind of insulation facing was originally put on that we have right now. The facing itself is exposed on the walls and ceiling besides the first 8’ of wall cover at the bottom. Do you know of any way to determine what type of facing we have? I attached a few pictures of it in case you might be able to help out with any guesses…

Thanks a lot for your help! JON in HANOVER

DEAR JON: Your metal building insulation has a WMP-10 facing, which is generally used in a typical metal building application where the walls are exposed to light to moderate traffic. It obtains a mid-grade durability. The front side is composed of polypropylene insulation facing, with a white kraft paper backing on back side. WMP-10 is slightly heavier than WMP-VR facing.


 

This entry was posted in Insulation, Roofing Materials, Pole Barn Planning, Trusses, Concrete and tagged , , , , , on by .
1.866.200.9657
Building KitPrice

Know more about our pricing.

Pole Barn Guru Blog

The industry’s most comprehensive post frame blog.

Ask The Guru

This guru will grant you the answer to one pole barn question!

Pole Building Learning Center

To help guide you in the design of your new pole building.

Photo Gallery

Look at our collection of building photos for creative ideas!

Paint Your Building

Lets pick out some colors!

Most Viewed Blogs

Ask The Pole Barn Guru

Latest Blog Posts

View All