Walls with exterior board insulation are addressed in Part II of the Guide. 2x6 walls are bigger than 2x4 walls. Two exterior walls constructed with 2×6 and 2×4 respectively, without any added foam or other insulation around the outside, show that 2×6 is superior to 2×4 exterior walls. 23 of 75 Exterior Insulated Wall Considerations Fully exterior insulated 2x4 wall with rigid insulation CLT wall panel with semi- rigid exterior Insulation Steel stud or wood frame wall with rigid exterior insulation Key design considerations: attachment of cladding through exterior insulation, air barrier/WRB details 24. They're harder to lift and the headers on exterior walls … Exterior wall insulation in new Buildings. Exterior wall insulation can be applied in a variety of building solutions, like External Thermal Insulation Composite Systems (ETICS), cavity wall, timber frame, ventilated façade or metal cladding. 2x6 construction- $1.00 sq/ft- Insulate with R-21 fibrous material . Wall – Exterior (2 x 4) R-14 Total Assembly (R-3.9 and a Vapor/Moisture Barrier for the Reflectix®) Note: Installation instructions and illustrated drawings are recommendations only, while proper local construction methods are the responsibility of the installer. Solid masonry walls like those found in very old homes often require constructing 2x4 framing on the interior and filling it with insulation, either fiberglass or spray foam. One option is to adhere rigid foam insulation to the concrete walls and then cover the insulation with drywall. Two-by-four (2x4) stud walls with true 4-inch depth. A wall's R-value refers to its level of insulation. To see a general compression chart, click here. Get free shipping on qualified R15, 2x4 Wall Insulation or Buy Online Pick Up in Store today in the Building Materials Department. With construction codes demanding higher insulation levels, the market share for this old standby has taken it on the chin from alternatives such as 2x6s with foam sheathing, structural insulated panels, and insulated concrete forms. What would others do in my shoes? It would be better to buy the product that best fits in the space. Construction materials are given an R-value, and a wall's total insulation level is determined by adding up the individual R-values of the wood, drywall, insulation and other materials in the wall. from conventional 2x4 wall construction to a more energy efficient wall system. Insulation for 2x6 Walls Use R-19 or R-21 kraft-faced fiberglass insulation for two-by-six (2x6) walls. With a 2x6 wall the dew point is at the middle of the wall whereas with 2x4 and insulation it would be much closer to the outside of the wall cavity. A 2x4 wall may be the better choice, and can easily outperform 2x6 with enough exterior insulation. Installed Insulation R-value: The thickness of double stud walls varies; however, walls with overall insulation thickness of 9 1 / 2 ” appear to be most common. Limitations and considerations: Thermal bridging through the studs and plates limits the wall’s system R-value. Before switching to spray foam insulation, Tom used to use polyisocyanurate panels that way—he would build a 2x4 wall, insulate between the studs with batting (paper face removed), then cover the whole thing with foil-faced panels and seal them with foil tape before putting up wall board. Bottom wall plates - in Northeast carpenters double them - one treated one regular; Top wall plates - there are always two; Window extension jambs; Door extension jambs; Extra insulation; Big Walls. Exterior walls will obviously have a better R-value. With this system, you build a house out of 2x4's, fibrous insulation, SOLITEX MENTO Plus weather resistive barrier outboard, INTELLO Plus smart vapor retarder inboard, and not much else. Hot Insulation for 2x4 Walls Most wall assemblies, especially those in older homes, are built with two-by-four (2x4) studs.Since modern two-by-fours are not 4 inches, the true depth of the wall cavity is 3 1/2 inches.In most wall applications, you will use R-13 or R-15 kraft-faced fiberglass insulation rolls for these two-by-four stud walls. Average U value- I have tried several times in ResCheck and could never get it to pass with 2x4 construction. That’s not a ton of insulation, but given that it is 2x4 walls I’m assuming it’s a reno and that’s about all the space you have. Not only do 2×6 walls require more lumber, but they require more insulation, as well. by Mike Sakowski of DrywallInfo.com. Another is to apply the foam and then build a 2x4 stud wall that can be filled with fiberglass or cellulose insulation. Strength While dead load strength between the 2×4 and 2×6 framing is virtually the same when 2×4’s are framed at 16” o.c. If R-30 were the target, 0.37*30= R-11 of exterior sheathing and R-19 stud space insulation would be one solution. So, let’s take a look at those numbers… If fiberglass batt insulation is used, an R-13 batt fits into a 2×4 wall, while an R-19 batt works in a 2×6 wall. 2x4 construction: $3.00 sq/ft- 2x4 construction and use 3” of closed cell foam in the cavity. Consideration #2: Insulation. $1.95 sq/ft- 2x4 construction, 1” exterior foam board and R-13 cavity. R-19 to R-21 is generally considered a well-insulated exterior wall. There used to be pretty much one way to frame a wall: 2x4 studs spaced 16 inches on center with plywood or OSB sheathing. Installing the insulation on the outside provides further protection of the walls and keeps them warm (important to reduce the risk of moisture condensation, in cold climates). Since exterior walls make up a huge part of the building envelope, it makes sense to do what you can to increase the energy efficiency of your home by adding insulation. He said that whether you frame with wood or steel the wall should be 2x4 with extra insulation on the exterior because of the dew point. Part I addresses all aspects of the wall construction as outlined in Table 1 and in Figure 1. The grade of batting will vary, depending on the wall that you’re insulating. One option is to adhere rigid foam insulation to the concrete walls and then cover the insulation with drywall. By compressing fiber glass insulation, you decrease the amount of air trapped in the material. Visit http://www.idi-insulation.com/ for all your insulation information. R-13 or R-15 batts are the best products for a 2x4 wall. The floor and roof loads are stacked on top of the inner wall studs.