If necessary, apply basement waterproofing sealer to the wall. What Is the Best Insulation for 2x4 and 2x6 Walls? The EPS and tar on the outside together will provide you will pretty good moisture protection for the walls, the only problem is that it is all but a foregone conclusion that the footing are in the wet ground. Basement insulation required by the 2012, 2015, and 2018 International Residential Code (IRC) is as follows: at least R-5 in climate zone 3, R-10 in zone 4 (except marine zone 4), and R-15 in zones 5, 6, 7, and 8 and marine zone 4. Apprecaite feedback as I can;t decide what's best as I'm trying to retrofit my basement. A hand-tool for the do-it-yourselfer - Measure, mark and cut drywall with one easy to use tool; also ideal for floor tile, carpet, linoleum, wood flooring, insulation, wood paneling, hanging pictures and blinds, cutting fabric, foam board, vinyl siding, plywood, ceiling tile, roof shingles, and so much more The furring strips will rest on top of the foam, with a 3/4-inch gap between the drywall and the foam insulation. Mike, Basement-wall insulation can be placed on the exterior side of the wall, on the interior side of the wall, or on both sides of the wall. Each section between floor joists needs to be insulated. Smooth or replace deteriorated surfaces and old parging with an appropriate type of new parging. For more information on this approach -- what I would call the standard approach -- see this article: Building an Unvented Crawl Space. Code is requiring we use kraft insulation in the framing,so . Finally, simply apply the rigid foam to the wall, starting at the slab and then pushing it back toward the ceiling joists as in the image below. With your plan and permit in hand, clear everything out of the basement and youre ready to go. Next, consider your climate zone and code-minimum R-values. R-TECH - Measure, Mark & Cut InsulFoam EPS. Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features. Press the board into place. The first step in insulating a basement wall is to install the polystyrene insulation (for more information we recommend reading: R Values Of Foam Board Insulation ). How to Insulate a Basement | This Old House - YouTube 0:00 / 8:57 How to Insulate a Basement | This Old House This Old House 1.94M subscribers 3.1M views 8 years ago Insulation Tips for. The biggest problem with basement foundations that cause mold is a misunderstanding of where the moisture is and where it wants to go. Nail 24 blocking about every 3 feet into the first floor joist to support the top plate. Here's a project done recently in BC - panels stuck directly to concrete walls with low expansion pro Sikka foam as per manufacturers recommendations ( Airboard ), then they were taped to really seal them up- before and after readings on the humidity were like night and day, and the temperature with zero additional heat in the basement. To finish the drywall, there is some debate about the use of paper or mesh tape to hide the seams in the panels. Choose Between Mounting Screws and Adhesives. This won't delete the articles you've saved, just the list. If you need future access to anything, just frame around it and cut out the opening when you drywall. foam board thickness - 1' or 2' ? Frame around protruding plumbing with 2x6s nailed to adjoining studs. FOAMULAR 150 2 in. Attach the Rigid foam insulation to the basement walls using special foam board insulation adhesive or with masonry screws. Problematic blowing agents are also used in most brands of closed-cell spray foam, so if you plan to use closed-cell spray foam, seek out a brand of insulation that uses one of the new, more environmentally friendly blowing agentsfor example, Heatlok HFO spray foam from Huntsman Building Solutions. In this article, well focus on the framing and some unique problems, such as: To tell if walls are damp from exterior water or just condensation from humid interior air, tape a 2-ft. square sheet of plastic to the masonry. Daylight basement gutted due to mold in drywall. A mold expert told me to put the board on top of the framing, not directly onto the concrete wall so the house can breath. Abut the channeled edge of the next panel against the installed corner panel. Snap a chalk line on the floor joists 2-1/2 inches away from the nearest obstruction and parallel to the wall. Once the preparation work is completed, you can begin installing rigid foam insulation. (Note that open-cell spray foam is too vapor-permeable to be suitable for basement walls.). Attach the Rigid foam insulation to the basement walls using special foam board insulation adhesive or with masonry screws. Should I seal these to retain the dryness? Attach the drywall to the stud framing. Mike, Next, snap the board along the scored line. If you purchase a product or service with the links that I provide, I may receive a small commission. Properly installed, basement insulation will save energy, improve comfort, and reduce the likelihood that your walls will be damp. [21] Other products that reduce air flow and are waterproof (Such as Tyvek Tape) are also suitable. ", Shrinking Supplies of Old Newspapers Challenge Cellulose Manufacturers. The batts are faced with paper. It is recommended that you apply a Foam Board Joint Tape (Such as Owens Corning HomeSealR Foam Joint Tape). See this article: "Insulating a Wood-Framed Floor Assembly. Make sure your adhesive is free of solvents, which can eat away at the foam insulation. Choose carefully between Polyisocyanurate, EPS & XPS or Mineral Wool & Hemp as the wrong choice can reduce insulation performance &, Basements in Canada & USA face serious challenges: fluctuating water tables, surface floods, thermal shock, radon gas infiltration, condensation, mold, mildew, rotting walls and, Crawlspaces are becoming rare for new home construction in USA & Canada. Fill the gaps with low-expansion spray foam adhesive. The bottom line is that its senseless to spend time and money finishing a basement if leaks or moisture will ruin your work or cause mold to grow. Thank you for the info. On the other hand, you may prefer to boost the assemblys R-value by insulating between the studs. The first step is to make sure your basement is dry. This has left the underside of our floors uninsulated. Using a more air-retardent fiber such as cellulose would be better than low-density fiberglass, but even crummy R19s would be better than nothing. Then snap the board on the score line. We are compensated for referring traffic and business to Amazon and other companies linked to on this site. Although not as traditional as fiberglass, cotton or cellulose insulation, rigid insulation is a much more effective alternative for basement insulation as it offers continuous insulation, no moisture absorption (read: mold growth), greater R-value per inch as well as superior effective overall thermal performance. Noise through the ceiling is a common complaint. I am installing 2" XPS foam board is my insulation for my basement. Use the drill and concrete screws to attach the furring strips. Plumb and screw the studs to the blocking for a solid wall. Finishing against cool masonry walls without creating moisture problems. That would provide you with waterproofing to prevent any mosture in the concrete from migrating into the wall assembly. Do not subtract studs. Squeeze a 1/4-inch bead of construction adhesive to bottom plates and position them. Extruded polystyrene foam on the interior must be covered with 1/2-inch drywall or another code-approved material for fire safety. When properly mixed, the cement should reach a peanut butter-like consistency. Cons Inappropriate taping on the joints between the boards and the sheet can cause the air to penetrate your building. I would suggest closed cell spray foam. If not, I'm sorry. Apply the foam boards vertically from the top of the basement floor to the sill plate with the edges tightly butted against each other. R-TECH Insulation on Exterior Walls. In order to attach and secure rigid foam board insulation to your basement foundation walls, you have two options. I needed to apply foam insulation around new windows to insulate the windows more and to be ready for another contractor to spray all basement foam insulation (old and new) with fire retardant paint per code requirements. Cut 24 bottom and top plates and lay out stud locations every 16 inches on each plate as youre insulating basement walls. You must be as useless as your comment to go attacking a single mom on a foam board Q&A forum. Because we build walls so they can't dry. And due to the laws of physics, moisture will always want to go where it is dry, which in this case will be your studs, at least until they are completely saturated to the point of equilibrium and the wood just stays as wet as the concrete wall. The modal window is a 'site map' of the most critical areas of the site. He proclaims that would be where my musty smell comes from. Next, liberally apply an adhesive as suggested by the manufacturer. Install the furring strips horizontally on the face of the insulation. We had to do several things differently to make that . 4. Before beginning to install rigid foam insulation on your basement concrete walls, ensure that there are no water or foundation issues in your basement. Thanks so much for checking out ATImprovements! We like to use a all purpose adhesive that's approved for Styrofoam products. The gap will be filled later with closed-cell spray foam. 2) Don't use a vapor barrier, such as poly, on the interior. If you were going to tackle the job of re-insulating such a space, what materials would you use, and where would you apply them? Rigid foam can be adhered to concrete with foam-compatible adhesive or can be attached with special fasteners like Hilti IDP or Rodenhouse Plasti-Grip PMF anchors. This air infiltrates the home in the form of drafts through walls sockets, windows and doorways. After being water-logged, fiberglass loses some of its R-value. The graphite offers greater R-value than regular EPS at R-5 per nominal inch but in a thinner product. If the intended cut point happens to fall on a pre-scored line, you can break off the foam there. Measure and Cut the Rigid Foam Insulation. You must be a magazine subscriber to access this feature. Complete DIY projects like a pro! If you choose to do your own electrical work, draw up and submit that plan as well. Wise advice appreciated. Then, to account for the foam's additional thickness, add jamb extensions to the windows and doors and fur out around their openings. Rigid foam board is typically made of polystyrene, polyiso foam, or sheets of polyurethane. Cut the tip of a tube of low-VOC foamboard adhesive with a. The US Department of Energy (DOE) studies show that 40% of your home's energy is lost due to air infiltration. It also offers continuous insulation, greater R-value and wont lead to mold growth. Next, measure and cut the rigid foam insulation to ensure that they are the correct size. The technology of basement insulation with foam from below is used for slab and shallow strip foundations. Most basements have ductwork and plumbing mounted at the ceiling along an existing wall. It comes down to four basic steps: Using a broom brush or a shop vac, clean the walls so they are free of any debris. Note that the IRC lists two different R-value requirements for basement walls: a lower number (for example, R-15 in zone 5) for continuous foam, and a higher number (for example, R-19 in zone 5) for cavity insulationusually interpreted as fluffy insulation like fiberglass installed between studs. This will create a vertical and horizontal gap for any future electrical wiring to be installed. Similarly, minor mold growths can be managed by a homeowner, but large and pervasive swaths can be difficult to manage. If you see any cracks, fill them with a repair substance. Foam board insulation is easy to cut with a circular saw with a masonry blade or scored with a utility knife and snapped like you would drywall. DIY Projects can be dangerous - attempt them at your own risk! It's a lot of work. Option One Cut the foam boards into strips that will fit in between the joists. 2. Boxing in those pipes and ducts and then drywalling the assembly is the best way to conceal them. Canada National Research Council, 2011. doi:10.4224/20373827, Section 2603 Foam Plastic Insulation. GPS, the latest advancement in rigid insulation, offers greater R-value, breathability and is less expensive than a product like XPS. Be sure to follow any specific instructions from the adhesive manufacturer. Clean Up and Finish Floor After all the caulking has dried, you can finish the floor or replace everything back on it. (Unsure how to get the cellulose evenly distributed in that area!). My question is since foam board is a vapor barrier and basement walls always absorb water from outside, by putting foamboard on the concrete, won't it trap water in the cement walls? After your band boards and joints are insulated, you're ready to spray. The existing floor needs significant leveling. Check the insulation manufacturer's instructions for the necessary thickness of plastic. The back of the framing can touch the front of the foam insulation. In your climate zone -- Zone 3 -- most codes call for floor insulation to have a minimum R-value of R-38. Align the dashed and cut line with the edge of a table, then press down to break the insulation board. Cut Furring Strips This site is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. Large sheets of 1- or 1-1/2-inch-thick rigid foam are attached directly to the foundation wall with concrete screws. Make a scale drawing of your plans to submit to your local building inspections department. After the cement is set, apply a foam board adhesive to the rear of a polystyrene insulation panel, then press the panel to the wall. Remove all the trim from the exterior wallswindow and door casings, baseboards, crown molding, you name itand rip the drywall and studs off the block walls. Sketch the details of the exterior wall construction you intend to use as we show in this article. Thanks so much for all your straightforward, honest answers. between the back of the studs and the concrete wall. Its a simple matter to frame or fur out around projections and then drywall and finish them to blend in with surrounding surfaces. Dont forget about airtightness as well. Insulation of slab and strip foundation from below. Nail on a 24 nailing strip using the chalk line to position the bottom of the strip. Synopsis: Former editor Martin Holladay outlines three ways to insulate a basement wall from the interior side of the wall to achieve minimum R-values in the space, with section drawings to illustrate each assembly. But, make no mistake about it: Finishing a basement is a big job. In unfinished attic spaces, insulate between and over the floor joists to seal off living spaces below. The full stud system is best for larger basements that need maximum insulating value. It doesnt require the use of any poly, staples and so on because it qualifies as a vapor barrier. Tools and Materials Needed to Install Rigid Foam Board Insulation, Rigid Foam Board Installation Preparation, How to Install Rigid Foam Insulation to Concrete Foundation Walls, How to Secure Rigid Foam Board to Basement Concrete Foundation Walls, Attaching Rigid Foam Board Insulation to Basement Foundation Walls Using Adhesive, Attaching Rigid Foam Board Insulation to Basement Foundation Walls Using Masonry Screws, Sealing the Gaps between the Rigid Foam Board Insulation, How to Build a Fence (DIY Guide) AT Improvements, How to Build a Fence Gate (7 Steps with Pictures & Video) AT Improvements, DIY Cable Railing How to Install Cable Railing Step-by-Step (atimprovements.com), DIY PAVER PATIO Easy DIY Paver Patio Ideas (atimprovements.com), Safety Equipment (Glasses, gloves, boots, ear protection, etc. It has two open vents covered with old wire. We recommend our users to update the browser. Interior moisture can enter the wall from air leaks or diffusion through the wall finish. Step one is to perform air sealing work at the perimeter of the floor (the rim joists areas). And its less expensive. Have put 6" of spray foam between the joists underside the building (aka outside). Rigid foam insulation is the material of choice for insulating against foundation walls in basements. A: Myron Ferguson, a drywall contractor in Galway, N.Y., responds: These days, rigid foam is usually installed on the exterior, but back in the '80s I installed a lot of drywall directly over interior foam board typically 1-inch foil-faced polyisocyanurate fastened right to the framing. For the concrete floor, it has about 1.5 inch gravel base and sump pump path underneath but there is still a couple of tiny damp spots sometimes. I am tentatively planning on 2" polyiso across the joists, air sealed with tape at seams and foam at edges, followed by blowing an all-borate cellulose on top. Framing and finishing a wall thats half masonry and half wood frame. 3. To do this, use a masonry hammer and center punch to tap the tie rods below the surface of foundation wall. But yes, we would put rigid foam boards against the wall THEN the stud wall, you don't want to have organic material exposed to moisture, particularly having a source of moisture on one side and an impermeable or semi-impermeable layer to follow. The whole structure is called a soffit. Let's revisit this question. And wouldn't that damage the wall overtime or force the water upward towards the sill? I don't know if its okay to comment on an old thread. Overlap the seams by about 12 inches and run the plastic up the walls at least 6 inches. Cut your polyurethane foam board insulation to fit these measurements. I live just outside of San Francisco, so weather is moderate but certainly not warm in the winter. 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