Dear Insulation DIYers
An open letter to DIYers tackling the Insulation scope of their project
Dear Insulation DIYers,
First off, wow! We are impressed that you are personally taking on the insulation scope of your project. We know firsthand how much work it is to do one trade correctly- let alone several! We are inspired by your dedication to tackling the insulation and air-sealing details of your project.
We want to empower you and be a resource for you during this time, whether you’re adding an addition to your house, doing a gut remodel, or building a brand new home. That’s why we’ve written this open letter, full of the practical advice and tips we have learned over the years insulating hundreds of different structures. If we don’t discuss something in enough detail, please schedule a consultation. We could talk for years about insulation and still not cover everything there is to know.
So, thank you for being here. And now, without further ado, here are our top tips and advice for Insulation DIYers:
PPE (Personal Protective Equipment)
This one is no joke. Proper PPE while visiting insulation-land is the difference between being able to see clearly out of your safety glasses and getting fiberglass insulation stuck in your eye. Trust us, it hurts. A lot. And it itches. Wear your safety glasses, folks. And gloves, and hard hats (especially when working in attics). And most importantly: your N95 masks.
Recent years have made almost everyone aware of the N95 mask. Chances are you still have them stockpiled in some dark corner of your house. Bring those babies out into the light of your insulation project and put them to good use. Insulation can and will leave you coughing for hours without the protection of a mask. We recommend this piece of PPE above all the rest (although, we deeply hope that you will use all types of PPE).
Our last piece of PPE advice is to buy a batt knife if you will be installing batt insulation. Unfortunately, utility knives don’t quite make the cut (😉), because the blade is simply too short. When you are working with batt insulation that is up to 12 inches deep, you definitely need a blade that is 8-12 inches long. Having the proper knife will help prevent blade slips and therefore injuries. Another consideration is maintaining the quality of the piece of batt insulation you are working with. If you have a 1” blade and a 12” piece of batt, you may have to slice the batt several times to cut all the way through. This can compromise the integrity of the batt and possible destroy it.
Code
It is easy to fall into the trap of thinking about building codes as extra hassles and hoops that simply need to be jumped through to reach the end goal of your project. At Thermal Shop we adopt a different frame- that building codes are really here to support, direct, and protect our projects- helping to ensure a healthy lifespan, low-energy maintenance, and overall high quality. In addition, building codes simply must be adhered to, so viewing them as helpful instead of hindering will allow any DIYer or professional installer to form a positive relationship with checking all the boxes. Knowing what is required before you start can also help you make a robust and detailed plan, and prevent things from getting missed.
Most of Iowa exists in climate zone 5, while some parts of Iowa reside in climate zone 6. Each climate zone and their associated building departments have different code specifications, inspection requirements, and overall implications as they relate to air-sealing and insulation. Get familiar with what is necessary to pass code in your particulate climate zone and building department.
We encourage everyone to visit this website where the 2012 International Energy Conservation Code is outlined in extreme detail. You can find all required R-Values and building details there. To get you started, below is a little cheat sheet for Climate Zones 5 and 6.
This is a huge and hugely important topic. If you are unsure, would like some guidance, or would simply like someone to double check your project plan, schedule a consultation with Thermal Shop today.
Attics
Install Baffles and Attic Rulers Before Drywall
Our biggest piece of advice here is to install ventilation baffles and attic rulers before drywall. This is for reasons of accessibility- baffles and attic rulers oftentimes are installed in the tight little corners where the pitched roof meets the ceiling. If drywall goes up, it becomes extremely difficult (if not impossible) to crawl down into that cramped space to install a baffle or attic ruler without injuring yourself. In this scenario, not only would you have to get down on your hands and knees (possibly your belly) while balancing your weight on attic trusses, you would also have to watch out for nails jutting through the roof above you. Not fun, and definitely not safe.
However with a little planning ahead, attic rulers and baffles can easily be installed before drywall goes up with the help of stilts or a ladder.
Ventilation
Now you may be thinking- why all this fuss over ventilation baffles? Well, not only is attic ventilation a code requirement, but it also contributes in a large degree to the health and lifespan of your insulation (and therefore, your entire project). It is critically important and often overlooked. If you are installing a traditional attic space with ventilated soffits, you need to ventilate your attic.
Staple Your Baffles and Blockouts
No matter what type of ventilation baffle you are using (styrofoam and cardboard being the main two types): staple the heck out of them. They will be directing air movements in a useful manner and if they get blown off by a combination of insufficient stapling and extremely strong winds, they will no longer be functional and even more difficult to replace. Because, in this scenario, not only would you have to crawl on your belly into that tight corner while protecting your head from roofing nails and balancing your weight on attic trusses, you would now have to do all of this while sifting through 12-18 inches of blown cellulose or fiberglass (and folks, that is practically impossible). Another reason to staple the heck out of your baffles: ice damming. Ice damming in wintertime is often due to improperly installed baffles or baffles blowing away, which in turns allows the insulation to be blown away and excess heat to escape.
If there are bays where it is impossible to install a baffle because of pipes, wires, ducts, or some other obstruction: install blockouts. Blockouts simply block air from entering the attic at that particular spot. We love to use scrap fiberglass batts for blockouts (densely packing them into the corners where pitched attic meets ceiling), and just like baffles, we staple the heck out of them.
The bottom line: Prioritize ventilation. Plan ahead of time to get important installations done in the easiest manner. And, if you think you have used enough staples on your ventilation shoots and blockouts, add a few more just to be sure.
Plan for an Entire Day of Work if Renting an Insulation Hopper
If you are planning to DIY your attic insulation and rent an insulation machine, then we’d propose planning on a full day’s work to pick up the machine, finish your attic, and return it. While industrial hoppers can normally blow an attic in just 1-2 hours, rental machines tend to be very well loved and function less optimally than one might desire. Air locker seals may be compromised, which leads to low air pressure and less material moving through the machine. The augers may be clogged or damaged. The hoses may have holes. To manage timeline expectations and avoid frustrations, plan on a full workday.
Walls
When wall systems are opened up due to gut remodels, renovations, or simply being at the insulation stage of the building process, a huge opportunity for improving the health and lifespan of your project is within your grasp: air-sealing.
Air-sealing keeps unconditioned air out, and conditioned air in. It’s an important step that is often and sadly overlooked, leaving houses and buildings with cold drafts, high utility bills, potential insect entry points, and shorter lifespans for the different components of the exterior envelope.
If you are at the store, pick up a few tubes of caulking and cans of foam. These items will more than pay for themselves as time goes on. Make sure not to miss caulking top and bottom plates, and foaming around all windows and doors, and in any penetrations into the attic and to the outside.
Rim Joist
If there are rim joists in your DIY insulation project, make sure to check them. Too many homeowners open up walls and inspect rim joists only to discover that they were never insulated in the first place! While this can be frustrating it is also an opportunity to bring your project up to current code standards. Rim joists can be insulated with batts or spray foam, and inaccessible areas can be reached with drill-and-fill blown insulation.
Sound Insulation
If walls are opened up, now may be the time to consider sound insulation. Sound insulation is just like thermal insulation, except that its purpose is to deaden sound transmission instead of thermal transmission. We wrote all about it in this blog post. If you enjoy quiet spaces, have loud housemates, or hate the sound of the dryer, sound insulation may be an important consideration for you.
Moisture Management
If your project has any flat-roof spaces (for example, an unventilated attic space), it is imperative that you seriously consider moisture management. Moisture management is included in building code for good reasons: without it, rot and mold will slowly develop and eat away at the integrity of your home or building. Code requires a minimum amount of vapor impermeable material (like foam board or closed-cell spray foam) to be installed and the particular amount depends on your climate zone. For example in climate zone 5, all unventilated attic spaces require a minimum of R-20 vapor-impermeable insulation. Check out table 1202.3 in the 2021 International Building Code for further information.
Here is our rule of thumb: Ask your local building department what is required. Typically polyethylene sheeting is used, but if the budget allows we highly encourage people to install a smart vapor retarder like Certainteed Smart Membrain.
And finally, If you happen to be installing a hybrid system (spray foam + fiberglass insulation) make sure you install enough closed cell foam to prevent the interior surface of the spray foam from becoming too close to the dew point. If you install too thin of a layer of spray foam the interior surface of the foam will get too cold. In addition, the extra fiberglass that will be required to make up for the too-thin layer of foam will generate a significant temperature difference between the fiberglass and the foam, which will then hinder the foam from getting warm enough to stay above the dew point. If the temperature of the foam falls below the dew point condensation will form. And by now I hope we all know what condensation can lead to inside of a wall: rot and mold.
If you’re unsure, give us a call to discuss hybrid options.
In Closing
Insulation is a big topic, and there is so much to learn and discuss. Insulation is also an important topic, as it directly correlates to your home’s comfort, efficiency, and lifespan.
Boromir says it best: One does not simply throw insulation into a wall.
If one does simply throw insulation into a wall, then that wall is likely to experience a short and expensive lifespan, cold drafts, insect infestations, and rotting from the inside out.
DIYers, make a high-quality insulation install a priority for your project. Your home or building (and your future utility budget) will thank you for it.
Warmly (😉),
The Team at Thermal Shop
P.S. If you’re not a DIYer, or you are a DIYer but you don’t like being itchy and insulation is very itchy, or if you’d rather just let someone else do all this complicated insulation stuff, then Thermal Shop will gladly handle the insulation scope of your project.
Reach out today to get the process started!
