InSoFast vs. Traditional Exterior Wall Assembly

In order to highlight the differences between InSoFast EX 2.5 panels and Traditional Exterior Wall Assembly methods, we have compared the two in terms of materials and cost. All numbers are based on the idea of working with a 2,400 sq-ft surface area, a wall that is 120 ft long by 20 ft high. We are not designing this wall for today’s minimum standards. We are exceeding them in preparation for future Net-Zero energy requirements.

For simplicity of comparison, we are ignoring the existence of windows and doors. Admittedly, InSoFast panels would require such openings to be framed, but in this scenario the overall cost would only increase by about $100.

Our comparison accounts for the rainscreen and R-10 insulation of an exterior wall. It is part of an advanced building approach that only 10% of the most energy efficient builders are using today. The other 90% won’t be forced to do this until after the 2020 building codes are adopted and most of them see no reason to aim higher. This is about durability and efficiency.

Our point of interest resides between the weather wrap that seals the exterior sheathing and the outermost aesthetic finish. We decided to finish the project with siding board because, in both applications, you can optimize your costs by using screws that were already purchased for other steps. Don’t let this limit your creativity. Both methods support a wide variety of finishes including stone veneer, stucco, brick and more.

All prices are based on the online sources represented in the hyperlinks below as of May 21th, 2015. Home Depot pricing varies by zip code, so our calculations reflect pricing found local to our office in Reading, PA. The totals do not reflect additional costs levied by taxes, shipping or labor and on that note we’d like to point out our free shipping and speed of installation.

We honestly spent a bulk of our time researching the most cost-effective products and places to purchase those products for the Traditional Assembly. If you think you could do better, please feel free to refute our claims in the comment section below!

Rainscreen System

Product: Slicker® Classic Rainscreen

This is a drainage layer that ensures moisture is able to flow away from the interior of your home. The project requires 16 rolls priced at $142.50 each direct from the manufacturer’s website.

$142.50 x 16 = $2,280.00

Fasteners

Product: 1-1/2 in. Plastic Round Cap Roofing Nails

These fasteners are required to secure the Slicker® Classic Rainscreen every 3 feet. They need to penetrate the sheathing by at least 1/2 inch to ensure optimal attachment of the product. The project requires 4 boxes priced at $5.86 each.

$5.86 x 4 = $23.44

Rigid Foam Insulation

Product: Owens Corning FOAMULAR 150 2 in. x 4 ft. x 8 ft. R-10 Scored Squared Edge Insulation Sheathing

This is that nasty pink stuff people use to insulate things. We don’t know why. The project requires 75 panels priced at $32.00 each.

$32.00 x 75= $2,400

More Fasteners

Product: EIFS PB Washer PBH & Wood Lite Metal Screw

These specialty fasteners are used to secure the pink stuff to the sheathing (after penetrating through the rainscreen). The project requires 3 boxes priced at $175.00 each.

$175.00 x 3= $525.00

Building Flashing Tape

Product: 3M All Weather Flashing Tape, Tan, Slit Liner, 4 in x 75 ft – 8067

Now you gotta tape all the seams because your insulation’s r-value is utterly moot without this finely laid millimeter of material. Yay. The project requires 12 rolls priced at $28.05 each

$28.05 x 12= $336.60

Furring Strip Boards

Product: 5/4 in. x 3 in. x 8 ft. Furring Strip Board

Now add some organic matter to this 6-layer sponge in a location just barely tucked away from where it will actually be dumping buckets of rain on your building. Space them 1 per lineal foot. The project requires 330 strips priced at $1.98 each.

$1.98 x 330= $653.40

Even More Fasteners

Product: HeadLok 6 in. Heavy Duty Fastener – 250 Pack

The final penetration! Use these fasteners to attach the furring strips to the structural sheathing, passing yet again through both the insulation and the rainscreen. With the furring for attachment, you can now use these screws to attach siding. The project requires 13 packs priced at $129.00 each.

$129.00 x 13= $1,677

Insect Screen

Product: Home Slicker Screen

Make sure bugs don’t nest in your assembly by running this screen along the bottom of your wall. The project requires 1 roll priced at $75.50.

$75.50 x 1= $75.50

TOTAL MATERIAL COST= $7,970.94

InSoFast EX 2.5 Panels

Product: InSoFast EX 2.5

Add InSoFast. The EX 2.5 panels are an all-in-one solution to the rainscreen/insulation/attachment fiasco depicted above. Yep, it’s all there. This project requires 60 boxes priced at $73.60 each.

$88.40 x 60= $5,304.00

Starter Track

Product: Starter Trac w/Drip Edge, 2-1/2 inch, 8′ Length

This serves as your bug screen for InSoFast. It also provides a drainage area and nice place to rest your first run of panels. This project requires 15 starter tracks priced at $22.81 per 8 ft length.

$22.81 x 15= $342.15

Fasteners

Product: Grip-Rite #10 x 4 in. Phillips Bugle Head Coarse Thread Sharp Point Polymer Coated Exterior Screws

First, screw the panels to your structural sheathing. It’s always best to line up stud with stud and the EX’s embedded studs are located every 16 on center. Next, attach the siding to the InSoFast stud. This project requires 9 boxes priced at $25.64 each.

$25.64 x 9= $230.76

TOTAL MATERIAL COST= $5,876.91

So there you go! We highlighted each material and step to the last tack and the results blew us away. One more time, that’s $7,970.94 and a whole lot of work compared to $5,876.91 with our single interlocking panel. It’s a difference of over $2,000 for a 2,400 square foot project.

Believe it or not, we didn’t engineer our product to be cheaper. We were way more focused on eliminating all the complex variables that can muck up your good intentions. We wanted something simple and effective. A secure, future-ready investment. The overall cost is just a bonus.