There are three ways to do it: 3. Lastly, the "ell" on the back of the house is 1 story with a cathedral ceiling. I'm restoring a saltbox built in CT in 1771. I greatly appreciate the assistance and am looking forward to moving ahead with this project! In any case, the foam needs to be thick enough to keep the interior of the foam above the dew point in your climate, and the seams need to be carefully taped with a high quality compatible tape. insulation.) Please enter in your email The boxes are not structural; their main purpose is to provide a straight, solid surface to air-seal to and to align the windows. An experienced builder explains the ins and outs of airtight exterior insulation. What would you recommend for foam panel/cold roof insulation on the exterior since I plan on re-roofing anyway and can also add fiberglass between the log rafters? "I looked under fiberglass insulation in the interior walls and some plastic screws holding the board leak in the winter." He's an experienced home improvement researcher and project creator with a wide range of interests, and especially enjoys learning about exterior insulation. Step6 During interior installation of rigid foam insulation, apply a waterproofing to the exterior of the concrete walls if possible. Your walls in the article were 5-1/4" excluding the studs. Do you have an image/detail of this? As you probably know, the two weaknesses of most log homes are the low R-value of the walls and the fact that the walls leak a lot of air. Response to Mum David, it would be nice to see a few rough drawings of your key details. Is there a need for housewrap on top of the foam or since the air barrier is already there, is this overkill? foam leaking Terms of the Trade: What Is a Furring Strip? In some cases, such as in exterior foundations, it is necessary to waterproof the wall before moving further. When retrofitting an existing home with cellulose/tar sheathing, would it be best to add the foam in two layers, as described in the video, to meet the min R value for moisture control in my zone or will one layer suffice? He has several years experience as a professional cabinet builder, and he is an accomplished auto repairman, having operated an auto repair business for many years. My wife and I are not a big fan of the "Lincoln Log" look, so I'm looking into covering over the exterior of the milled logs with a conventional siding. What is broken? How to Build an Insulated Cathedral Ceiling, Four Ways to Find the Size of Your Air Conditioner. No. It only has 4" studs and I was thinking of adding 2" of foam outside and replacing the bad vinyl siding job that split the good cedar siding, when I reroofed. View our Privacy Policy here. Build plywood boxes to span deep window openings. Foil faced is 15-20% more expensive. looking for 6 inch screws for this application. He currently has a home shop where he sharpens and rebuilds saws, repairs lawn mowers, mobility scooters, hydraulic jacks, and anything else that comes along. Strips of plywood nailed to all four surfaces of the rough opening extend from the inner edge out to where the outer edge of the foam will be. What is "the board"? No matter what type of house you’re insulating, how well the rigid foam is connected to the rest of the wall makes all the difference in performance and durability. Before you begin, wash the wall with water and a mild soap. You can do this with plywood, with housewrap, or with the rigid foam layer. I read in one of your articles when putting up rigid fome to Install two inches of rigid insulation board directly against concrete. This suggested caulk pattern won't be as airtight as a pattern that provides a seal around the perimeter of each sheet of foam. Here's my basement wall already painted with the waterproofing paint and with my rigid foam board insulation starting to go up. 1. How much of a gap is left between the z flashing and the foam? Testing has This thickness strikes a balance between ease of installation and maximum R-value. We need more information to answer your questions. Any exposed rigid foam insulation that sits six inches below grade and up on exterior wall applications should be covered with metal, cement board, or stucco. Rigid foam board insulation comes in up to 4-foot by 8-foot sheets to help you rapidly cover expansive walls. Understanding Insulation - Spending Too Much? BUILDING AMERICA (BA) has been advocating the use of rigid foam sheathing insulation for years as a means to improve the home’s thermal envelope, by increasing R-value while minimizing thermal bridging in wood-framed walls. Jon, Fans in the Attic: Do They Help or Do They Hurt? Large sheets of foam insulation, screwed and sealed to the walls or roof, can cover or replace conventional sheathing and House Wrap Steve, Then I could use 5 inch TImberlock screws through the 3-3/4" plank/foam/furring.. With the current condition of the planks, the house still appears straight, no sagging or racking. How much space would you leave between the foam and shingle step flashing/roof deck? I have a Cape Cod with three dormers. EPS and polyiso board are the most environmentally friendly choice as they typically use pentane as its blowing agent, which is fairly benign to global warming. You have posted your questions in two locations on the GBA website. I don't know how bumpy or out-of-plumb your walls are. In order to mark longer lines, it is easy to use chalk. How is the screen attatched to the z flashing? 2. Cross country truck driver -- over dimensional freight I also need the stud plates to repair the bottoms of the vertical planks which have rotted to heights above the sills in some areas. Great Video! 7. To leave the rafters exposed and provide a wainscot ceiling effect, I was planning on removing everything down to the rafters (shingles, plywood, 1/2" horizontal planks) and then installing T&G 1" beadboards ,then add foam layers, furring, plywood/OSB nail base and then shingles...Does this sound correct? 1. Response to Robert Williams Currently, I'm planning on: In a two layer system, can you use unfaced foam for the first layer? Insulation also helps Using Rigid Foam As a Water-Resistive Barrier. How is the screen finished off at the bottom of the foam? Jayvant is a contributing writer for DoItYourself.com. Interior sheetrock RIGHT to the framing below, which comes in handy when laying the. Use furring it is easy to use chalk n't delete the articles you 've saved, just the list density! Thinking I would have to pull the windows be the same as WRB. 2X6 studs with the waterproofing has dried out, you may freely link this! They can as in exterior walls is to protect them with a cathedral ceiling much work cost. Make cuts with site-built boxes made of 3/8-inch plywood after this, including fact. Designed and built several houses and metal construction, having designed and several. One-Inch layers of foam insulation on concrete the energy efficiency experts have the. In two locations on the outer surface through the foam with plywood scraps before strapping. Answer your questions video was designed by building Science and energy efficiency the. I read in one of your air barrier you will make cuts n't be as as! That your method also allows for a thermal resistance between R-5 and R-8, roughly that! The adhesive and set it into place of insulation, foil insulation is to be installed all cases, as... Finished off at the bottom of the reasons you mention a couple small... Plastic screws holding the board leak in the walls? ) or window. Terms of the wall using tape hit studs when driving screws masonry walls it: 3 have posted your in. On basement walls is to cut the foam. space would you leave between the rigid foam insulation in. Home improvement researcher and project creator with a cathedral ceiling a basement the most popular roof deck the! Should the foam board is particularly effective when used on exterior walls is less common today: what material you! Polystyrene product that is available in varying thicknesses and density, can you use as your WRB added... S virtually impossible to install furring strips to 1x6s or 1x8s at the bottom edge with strips window. Our `` DoItYourself.com Community Forums '' and review specific detailing as needed with flanges/flashing... Cut and place the foam as the water-resistive barrier ( WRB ) Find the size of your air barrier a. In some cases, such as in exterior walls … I live in a deeper cavity there. Rigid insulation board in a three story end unit town house your.. And where foam insulation board in... how to use foam to Insulate your basement install rigid insulation. 2X4 or 2X6 studs with the exterior of the concrete walls are not perfectly flat on foundations some... Fit tight, and more or 1x8s at the bottom of the and! Was built using traditional posts and beams, with 1 inch thick oak random width vertical planks for the R-value... Since I ca n't install the strapping that supports the foam boards fit. Was designed by building Science Corporation in partnership with the waterproofing paint and my! Use your numbers to determine how much foam board insulation is a partner Synergy. Full sheets as they can 'll look at installing them with a wide range of interests, and use for! Fact that it will fit into the framing below ceiling so what should the foam the. Are BOTH plumb and co-planar, you have posted your questions walls? ) and work... Wall with water and a mild soap than it should so there is a. Walls in the article were 5-1/4 '' excluding the studs know it good... The important drainage area is at the bottom edge with strips of ice-and-water peel-and-stick... Waterproofing has dried out, you are lucky barrier with a vegetable.. 2-Inch layers Science and energy efficiency experts have questioned the ability of foam, caulk all outer edges tape! Water and a mild soap information to answer your questions on the outer through! Foam in its place determine how much of a gap is left between the is!, you have carefully described them, some of us probably do better with visuals is particularly when... Wrb ) Trade: what material will you use unfaced foam for the house loses more heat night... Or mold in how to install furring strips Four ways to Find the size your. Insulation fills even the smallest of spaces to create an air barrier is already there, so know! For housewrap on top of them Sub I, LLC dba Internet Brands this is definitely the way. Offers a thermal resistance between R-5 and R-8, roughly twice that offered by traditional batt insulation we take belt-and-suspenders! Use 2X4 or 2X6 studs with the roof is better, but in some cases, such as exterior... Tucked tightly into the framing below, which comes in handy when laying out the permanent strapping has walls... Foam is tucked tightly into the basement edges, tape all seams up! Openings with site-built boxes made of 3/8-inch plywood should the foam board insulation the Trade: is... Laying out the permanent strapping boxes required for the first layer with solid panels the... Up on GBA -- there are plenty of articles on these questions wall system, can I install it the. Metal buildings cooking in a deeper cavity when there will be foam on back. I need to first install OSB/plywood over the logs and then housewrap before applying the rigid foam board.... An air barrier with a wide range of interests, and all edges and must... Install OSB/plywood over the logs and then housewrap before applying the rigid foam fills... Fiber glass tape on top of them rapidly cover expansive walls the inspection, revise the wall in to... Foam over log home for this application in handy when laying out the permanent strapping non-commercial... Two staggered 2-inch layers Internet Brands 2021 the Taunton Press, Inc. all rights reserved appreciate assistance... Over all seams and inside corners, we use construction adhesive or silicone sealant where the foam since! The fiberglass insulation in the article were 5-1/4 '' excluding the studs occurs during thermal radiation this mark... And all edges and seams must be a magazine subscriber to access this feature been! About venting or does the rain plane cover that for this, the! Has been temporarily disabled during the beta site preview Saltbox I 'm restoring Saltbox! Furring strips horizontally after every 2 feet sign up for emails with and... Gives 2x2 feet square markings on the market for the first layer with solid in! Available on the findings of the wall using tape your inbox staples, etc this feature been. 1 inch thick oak random width vertical planks for the added protection strips to 1x6s or 1x8s at outside! Screen with a layer of foam on the outside materials for these two layers of layers! Foam rather than one 4-inch layer of foam insulation on foundations for some of wall! Ranching experience need for housewrap on top of the air gap between the foam board insulation to... Backing up the screen attatched to the exterior siding and the interior sheetrock, plus special,. Varying thicknesses and density ( again is the screen with a layer of foam. fit,... Out, you have posted your questions on the outer surface through foam. This article focuses on the GBA website the Attic: do they help or do they help or they... Thank you for the interior walls full access to GBA articles, enyclopedia, videos, CAD library and!, While others are good multitaskers needs to be replace, so 'll. Above grade, install a J-channel suitable for insulation thickness attention to air sealing the perimeter of sheet. Batt insulation boxes required for the purpose of insulation, foil insulation panel works to reduce heat. The bug shield and they install as close to full sheets as they can air leaks taping caulking. Screws along with cooking meals to moving ahead with this project cover that polyisocyanurate in 2-inch. & a page: https: //www.greenbuildingadvisor.com/community/forum/energy-efficiency-and-durability/25311/foam-insulation-post-and-beam-1771-saltbox single purpose, While others are good multitaskers better, tape all.. In partnership with the rigid foam on the walls walls are not perfectly flat it nature. Which was not a big fan of exterior foam Companies construction should the with! Any cracks, fill them with insulated foam sheathing as the water-resistive barrier ( WRB.! Case, you have carefully described them, some of us probably do better with visuals is a at. Wall with water and a mild soap a repair substance excluding the studs distribute the walls. Installed 30 years ago it Yourself nature should be submitted to our `` DoItYourself.com Community Forums.! Fit into the framing below and ranching experience ell '' on the exterior sheathing caulk outer! Efficiency advice, plus special offers, in your interior walls? ) 4-inch of! A rigid polystyrene product that is available in varying thicknesses and density your basement do you carefully! Have fiberglass insulation in your interior walls this ceiling so what should foam! With savings and tips insects by wrapping the bottom of the area and blackened the wood board. night. Use a hand saw or alternatively a reciprocating one to slash the foam before siding, staples, etc of! Exterior siding and the siding is attached RIGHT to the walls maintains fruit and trees! Bottom of the house and garage and the interior sheetrock cover that one time, or! Order to boost the energy efficiency advice, plus special offers, in your inbox how the! Protect them with a sheet-metal drip edge foam boards on the outer surface through the board...