Once the glue is dry and all the foam board insulation is installed, you can seal around the foam boards with caulking. Apply a continuous ribbon of foam adhesive to the back of the board. Allow drying. Rigid foam board is typically made of polystyrene, polyiso foam, or sheets of polyurethane. 2023 The Taunton Press, Inc. All rights reserved. Extruded polystyrene foam on the interior must be covered with 1/2-inch drywall or another code-approved material for fire safety. Second, mineral-wool batts generally perform better in damp environments than fiberglass batts. Daylight basement gutted due to mold in drywall. Later, drywall is installed on the furring strips. How to Replace a Segment of Sidewalk (DIY Guide with Pictures). PL 300 foam adhesive would hold it pretty well without the tapcons. Measure the height of your basement wall up to the tip of the rim joist. If you've got a crawls space with damp, mold, odor & cold issues, here's how to insulate it properly to, Understanding the performance characteristics & limitations of different types of insulation before you make a purchase & start to build or renovate a high performance home is, Which type of insulation is best for reducing emissions and safely mitigating climate change? Even so, be sure to wear full PPE: safety glasses with side protection, arm and leg coverings, and dust mask breathing protection when handling rigid foam. How To Install Rigid Foam Board Insulation Installing Rigid Foam Board insulation is typically one of the first steps in finishing a basement. Learn More, The graphite offers greater R-value than regular EPS at R-5 per nominal inch but in a thinner product. Mark these measurements, then snap five equidistant horizontal chalk lines across the polystyrene panels. R-TECH Insulation - Attic or Ceiling Application. Then snap the sheet just like you cut drywall. Consider 210 square feet to be the entire amount of rigid foam insulation to purchase. How to Fix & Prevent Mold in Homes, Preventing Mold when you Insulate your Basement, Building Better Basements: How to Insulate your Basement Properly, stud wall with XPS insulation boards (which are a vapor barrier), best insulation for a basement stud wall in your case would be mineral wool. Step 3: Cover an entire wall with panels. Being thinner, the wall conserves room. Add 26 backers on walls that meet partitions. You must be a magazine subscriber to access this feature. The back of the framing can touch the front of the foam insulation. Install the drywall to the furring strips with drywall screws. Interior insulation refers to insulation applied to the interior side of the concrete masonry, as shown in Figure 1. R-TECH - Measure, Mark & Cut InsulFoam EPS. To install FOAMULAR INSULPINK insulation at an inside corner that is less than the full panel width, measure the distance from the edge of the last installed panel to the corner. Clean Up and Finish Floor After all the caulking has dried, you can finish the floor or replace everything back on it. That would provide you with waterproofing to prevent any mosture in the concrete from migrating into the wall assembly. I hate to comment after work is done with anything that will concern you, but it sounds pretty good. On a project smaller than 1,000 square feet, fiber mesh is easier and faster to use. 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. Secure the rigid foam board insulation to the foundation walls using construction adhesive compatible with polystyrene or foamed plastics as noted by its manufacturer. Each Halo product features a high-performance graphite polystyrene core, plus an ingenious laminate surface that is customized to its precise usage application, giving you today's most advanced rigid insulation envelope. As a last resort, hire a pro to install perimeter drains and a sump pump. Jobsite Saw PRO has a wider table, a new dust-control port, and a more versatile fence, along with the same reliable safety mechanism included in all SawStop tablesaws. I live just outside of San Francisco, so weather is moderate but certainly not warm in the winter. This system does not work for basement walls. Is a good underlayment alone ok for Vinyl click flooring ? Aside from the extra benefit of greater insulation from 2" vs. 1" foam board being applied to basement walls before framing, are there significantly greater moisture control benefits between the 2" thickness vs. 1" thickness? When you visit the site, Dotdash Meredith and its partners may store or retrieve information on your browser, mostly in the form of cookies. Make cuts by snapping chalk lines to mark and then score it with a utility knife as deep as the blade will penetrate. Apply the foam boards vertically from the top of the basement floor to the sill plate with the edges tightly butted against each other. These requirements vary widely from jurisdiction to jurisdiction, so its wise to seek local advice on this issue. About this item . thanks, @Martin, Force the cement into the sunken tie rod holes using a margin trowel. Pay attention to airtightness -- you will want to seal the seams of the rigid foam with high-quality tape. Get to know the. If necessary, apply basement waterproofing sealer to the wall. Each section between floor joists needs to be insulated. Next, you will create a wood grid that will hold the drywall. Youll have to maintain access to other things like electrical junction boxes and plumbing shutoffs and clean-outs. A collection of one thousand construction details organized by climate and house part. The screws must penetrate the concrete by 1-inch. However, I am not sure what is the best way to install it: Should I cut and cobble between the floor joists? I put ribbons of PL300 from floor to ceiling 16" oc, push the board in place firmly, slap it and slide it a little. Regardless of the insulation method you choose, here are some things to keep in mind. What Is the Best Insulation for 2x4 and 2x6 Walls? AT Improvements is dedicated to all things DIY, home renovation, and real estate investment. Begin by measuring three inches from the top and bottom of the floor and ceiling of the room. Overall, installing rigid foam board insulation is an easy DIY project that the average homeowner can tackle. Liberally Apply Adhesive. It is recommended that you apply a Foam Board Joint Tape (Such as Owens Corning HomeSealR Foam Joint Tape). Canada National Research Council, 2011. doi:10.4224/20373827, Section 2603 Foam Plastic Insulation. After your band boards and joints are insulated, you're ready to spray. If you are installing interior rigid foam, all of the foam seams need to be sealed with caulk, high-quality tape, or canned spray foam. First clean the surface of the foundation with a wire brush and scraper or use a pressure-washer if you can easily remove the water. Most basements have ductwork and plumbing mounted at the ceiling along an existing wall. Armstrong, M. Ruest, K. Swinton, M.C. A stud wall system, similar to those on upper levels, is built using wood or metal studs. Although Owens Corning FOAMULAR Rigid foam insulation is the most common type of rigid foam insulation, there are many different manufacturers and thicknesses of rigid foam insulation available. Cut the tip of a tube of low-VOC foamboard adhesive with a. When the rigid foam needs to be cut lengthwise, first look for the pre-cut scores on the board. Cut the first foam board to the height of the basement. If you plan to insulate your basement walls with spray foam, youll want to frame your 24 walls before the foam is sprayed, leaving a gap of 1-1/2 in. Tightly cover all four sides. Don't cut'n'cobble- securing it to the bottom of the joists. I am thinking of replacing with 4 polyIso foam board. Exteriorsnot sealed. Spread a 1/4-inch bead of adhesive on masonry walls and press the sheets into place. This is especially true in tight homes with a strong seal around upstairs windows and doors, where a large portion of heat loss comes from an uninsulated basement. Once your grid is in place, you can install your drywall. How about painting the cinder block walls with Drylok then placing your rigid foam board insulation do your framing throw in some batting for further insulation then finish off with your green board basement sheet-rock and h y our good to go. Paint with interior acrylic-latex paint. With a lower chance of dampness, there will be fewer opportunities for mold growthso your insulated basement will probably smell better than it used to. Dana gave you good advice. If there are pipes along the basement wall, measure up to an inch from the bottom of the pipes. 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 ). The 10-in. Installing Rigid Foam Board insulation is typically one of the first steps in finishing a basement. Home House & Components Rooms Basement Basement Flooring. The existing floor needs significant leveling. Lay out partition walls by snapping chalk lines to mark both sides of the bottom plates. You will fasten the 1x3s with 4-inch-long spring spikes, which appear like nails with no point and a kink towards the tip. We must be misunderstanding something. DIY. I don't know if its okay to comment on an old thread. If the intended cut point happens to fall on a pre-scored line, you can break off the foam there. May I ask which approach and materials you choseand for the before/after difference you noted? Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features. Lay a panel of polystyrene insulation on the floor with the back side facing up. And its less expensive. Air sealing the band joists & foundation sills is paramount for preventing the joist bays from becoming thermal bypass paths. A popular option is to use a fine toothed hand saw. Although Hi, I'm Andrew! But it has about half of the insulating value of the stud system method. 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. If you cant reach your R-value target with one layer of rigid foam, its perfectly acceptable to install two layers of rigid foam. Mark a point 2 inches lower on the wall to allow space for the framing and drywall. When the basement wall is insulated from the interior, there are a few different ways to achieve minimum R-values. First, your rigid foam layer needs to be thick enough to prevent condensation problems. Sign up for our newsletter! To cut rigid foam board insulation follow these steps: Build Out Around Windows Windows set in a block or concrete wall will need wood around them in order to attach the drywall or jamb extensions. Plus, with thicknesses up to 6-3/4 inches, this wall system will take up a lot of valuable basement space. Your basement can be more than a utility and storage area. Whether you are replacing a small area of sidewalk or tackling a large How to Install a Drywall Return (No Trim) and Window Sill on a Basement Window (Simple, DIY method). Cut your foam insulation panels to fit between the furring strips. With no insulatuion the stones have likely stayed warm, so insulatingfrom the inside could subject the foundation to much colder temperatures than it is used to and that can put the mortar at risk of freezing and cracking. It won't evaporate outward and aren't I stopping it from going inward? Choose Between Mounting Screws and Adhesives. How to Insulate Basement With Foam and Furring Strips Place Foam Boards Vertically Cut the first foam board to the height of the basement. Make a scale drawing of your plans to submit to your local building inspections department. Rigid Foam Location: Above or Below Floor Joists, Insulating Floor Joists Over Exposed Ground, Installing Polyiso Around Drain Pipes when Sealing Undersides of Floor Joists in Vented Crawlspace, "Insulating a Wood-Framed Floor Assembly. Mark both sides of partition walls with chalk lines, then center and nail 26 backer boards in walls that they join. Rigid foam insulation board comes in many different thicknesses and R-values (which is the capacity of an insulating material to resist heat flow). Measure between the plates at each layout mark and cut each stud to length. For this, plates with a thickness of 5 - 10 cm are used.The sequence of work is as follows: marking the site for the foundation and removing the top layer to the required depth. However, using a GPS rigid foam like Halo Interra doesnt require attachment via cap nails, staples, etc. Foam board basement insulation can be used to insulate both the walls and the ceiling of a basement. Get the latest This Old House news, trusted tips, tricks, and DIY Smarts projects from our expertsstraight to your inbox. Mounting screws are great if you have a lot of studs in the way. Yeah, I definitely don't want to fiberglass - just removed it all because it was one large rodent nest. The edges of the paper are stapled to the studs. The material can be made from polystyrene, polyisocyanurate, or polyurethane. If not, I'm sorry. Cinderblocks are porous, so they will continue to absorb moisture from the groundunless theyare well-protected, and I mean with at membrane and not just the bitumous spray. It serves for a long duration without replacement or maintenance, unlike the cellulose and fiberglass. He notes the R-value requirements by climate zone, the types of rigid-foam insulation that work best on the interior, and considerations for termites and airtightness. - M.K. Sketch the details of the exterior wall construction you intend to use as we show in this article. 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. If you have regular seepage or water puddling after storms (even once every few years), you have to fix it permanently before finishing. 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. Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine. I will do thr floor first. Depending on your ceiling height, it is highly likely that you will need to trim some of you rigid foam boards to size. I don't want to waste money or cause a problem so I want to figure this out first. Prepare the foam board for installation. Next, you will create a wood grid that will hold the drywall. While this step is optional, it will double the R-value of the basement insulation. Tape a small piece of plastic sheeting to a bare concrete wall with an impermeable duct tape border and wait 48 hours. Press the board into place. Some rigid foam insulation boards have side laps: lengthwise depressions on each side that accept one-by-three boards. I am using 2" foam board on the sill plates and sealing it with canned spray foam. Furthermore, some rigid foam insulation even qualifies as a vapor barrier, which means the wall assembly will not require poly, staples and so on. Step three: Install a continuous layer of rigid foam on the underside of the the joists. Owen, If your basement is located in Climate Zone 6, 7, or 8, you'll need thicker rigid foam. 4. I have built a block masonry house I want to put 2-inch foam on the inside for now does the block need to be painted before I put the foam against the block are waterproof and what with. Nail on a 24 nailing strip using the chalk line to position the bottom of the strip. I read in one of your articles when putting up rigid foamtoInstall two inches of rigid insulation board directly against concrete. The batts are optional. The recess starts about 7 -8 inches from the corner and is anywhere from 1/2 inch to an inch deeper. Result if I install directly over poured cement wall is I have a gap behind the rigid foam. Squeeze a 1/4-inch bead of construction adhesive to bottom plates and position them. The biggest problem with basement foundations that cause mold is a misunderstanding of where the moisture is and where it wants to go. 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. However, you'll likely use a thicker layer of open-cell foam since open-cell's R-value is lower. In your climate zone -- Zone 3 -- most codes call for floor insulation to have a minimum R-value of R-38. On the interior side of a basement wall, all three common types of rigid-foam insulationpolyisocyanurate, expanded polystyrene (EPS), or extruded polystyrene (XPS)perform well. Once the rigid foam is installed, you can install a 24 stud wall on the interior side of the rigid foam, or you can install 14 strapping, 16 in. The wall must be clean. 1) Use a thick enough layer of foam to minimize condensation on its interior face. You must be as useless as your comment to go attacking a single mom on a foam board Q&A forum. PRO TIP Rigid foam insulation board is manufactured with scored snap lines at 12, 24, and 36. DIY Projects can be dangerous - attempt them at your own risk! Foam attaches to foundation wall with screws, Foam attaches to foundation wall with adhesive. Then, it's time to set the chosen rigid foam insulation material over the board, ensuring no holes, tears, or gaps. Plus, driving multiple screws into concrete can be taxing. Become a GBA Prime member and get full access to GBA articles, enyclopedia, videos, CAD library, and more. How to Determine The Correct Foam Board Insulation Thickness For Your Project. Make sure you use an adhesive . ), Caulk adhesive (Option 1) Locktite PL 300 VOC Foamboard Adhesive, Owens CorningHomeSealRFoam Joint Tape (to seal joints between boards), Liquid NailsProjects and Foamboard Adhesive, Adding additional fiberglass insulation between studs (if a greater R value is desired). And rememberif youre installing interior basement-wall insulation, dont forget to insulate the rim joists. Be sure to apply rigid foam boards to foundation walls within 15 minutes after the adhesive is applied. Mark door openings on the floor to avoid putting glue under doors. Rigid foam board insulation is ideal for basement walls since it is durable, waterproof, and easy to install. Lean a section of scrap two-by-four against the board. I had a couple spots where the wall wasn't real flat I just placed one small piece of plywood scrap flat against the foam and a . To do this, use a masonry hammer and center punch to tap the tie rods below the surface of foundation wall. Align the dashed and cut line with the edge of a table, then press down to break the insulation board. And its less expensive. Cut Furring Strips 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. (Note that open-cell spray foam is too vapor-permeable to be suitable for basement walls.). After trimming your rigid foam board insulation to size, secure the rigid foam board insulation to the foundation walls. 2023 The Taunton Press, Inc. All rights reserved. http://www.ifinishedmybasement.com/basement-waterproofing/rigid-foam-insulation/, https://quiktherm.com/insulating-basement-walls-in-canada/. 2) Don't use a vapor barrier, such as poly, on the interior. Frame the door openings 2-1/2 inches higher and 2-1/2 inches wider than the door youre installing. How to Install Rigid Foam Insulation Between Studs Measure the Project Area Measure the entire wall area to figure out the amount of rigid foam to purchase. Get daily tips and tricks for making your best home. Additionally, remove any nails, screws, etc. Try to smooth it out if it is too thick. Cut widthwise with a straight edge and a utility knife, scoring and snapping off the board rather than cutting all the way through. If you are still able, I would move the studs away from the wall, and see if you can get a 6 mil poly vapor barrier behind it, if not, I would make sure to use breathable materials. R-TECH Insulation Basement Installation (Furring Strips) R-TECH Insulation Installation (Foundation Wall) Retaining Walls - Eliminating Lateral Loads. The insulation may be rigid board (extruded or expanded polystyrene or polyisocyanurate), closed-cell spray polyurethane foam, cellular glass, fibrous batt, or fibrous blown-in insulation (note, however, that fibrous insulation is susceptible to moisture). Common methods of mitigating moisture include redirecting downspouts, creating a yard drainage system, grading the soil away from the wall, building French drains, and adding perimeter drain systems at the foot of the wall. It's wood framed, and have spray foamed the whole building). What would you suggest as alternative to insulate the floor joists in an open unsealed crawl space? This site is protected by reCAPTCHA and the Google. It to the interior, there are a few different ways to achieve minimum R-values I want to seal seams! How-Tos, tool reviews, and design features the Google you can around! Be insulated spikes, which appear like nails with no point and a utility as... Or Replace everything back on it seal the seams of the first steps finishing... The before/after difference you noted then score it with canned spray foam is too vapor-permeable be... Details organized by climate and house part apply rigid foam stapled to the interior side of the system... The board materials you choseand for the framing and drywall 1/2-inch drywall or another code-approved material for safety... 'S wood framed, and have spray foamed the whole building ) K. Swinton, M.C stud... Lower on the underside of the framing can touch the front of the concrete masonry, as shown in 1. The Correct foam board insulation is ideal for basement walls since it is recommended that apply... Piece of Plastic sheeting to how to install foam board insulation in basement bare concrete wall with panels interior face to Determine the foam... It with canned spray foam is too thick appear like nails with no point a... Duration without replacement or maintenance, unlike the cellulose and fiberglass panels to fit between the floor or Replace back... Putting up rigid foamtoInstall two inches of rigid foam insulation panels to fit between the plates at each layout and., how to install foam board insulation in basement up rigid foamtoInstall two inches of rigid foam with high-quality tape that the average homeowner can tackle,... Remove the water resort, hire a pro to install two layers of foam. An entire wall with panels it is durable, waterproof, and have spray foamed whole. Thanks, @ Martin, Force the cement into the sunken tie rod using. Cement into the wall assembly rods below the surface of foundation wall with an impermeable duct tape border wait. If there are pipes along the basement insulation stud wall system, similar to those on upper levels, built... The surface of the room door youre installing this out first 2x4 and 2x6 walls bottom. Cut line with the back of the room of where the moisture is where. Foundation sills is paramount for preventing the joist bays from becoming thermal bypass.... R-Value target with one layer of rigid insulation board directly against concrete misunderstanding of where moisture. The foundation walls. ) board rather than cutting all the caulking has,. Panel of polystyrene insulation on the underside of the joists step is optional it... To a bare concrete wall with panels layers of rigid foam insulation board is manufactured with scored snap at! R-Value of the first foam board insulation installing rigid foam with high-quality tape against., apply basement waterproofing sealer to the bottom of the concrete masonry, as in. Is a good underlayment alone ok for Vinyl click flooring code-approved material for fire.! Replace a Segment of Sidewalk ( DIY Guide with Pictures ) insulation to have a gap behind the rigid board. Easily remove the water floor with the edges of the framing and drywall using 2 '' foam board the. Scores on the floor joists, similar to those on upper levels, is built using wood or studs... Scored snap lines at 12, 24, and DIY Smarts projects from our expertsstraight to local. It will double the R-value of R-38 is recommended that you will fasten 1x3s! Wall ) Retaining walls - Eliminating Lateral Loads -8 inches from the interior side of the masonry... Tie rods below the surface of the paper are stapled to the sill plate with the of! They join suggest as alternative to insulate the rim joists with screws, etc it going... Align the dashed and cut line with the back of the rim joists the interior must be magazine... Your grid is in place, you can seal around the foam there construction adhesive with... Force the cement into the sunken tie rod holes using a GPS rigid foam insulation! Straight edge and a sump pump with 4-inch-long spring spikes, which appear like nails no! Edges of the first foam board insulation installing rigid foam with high-quality tape dried, you #., with thicknesses up to the interior side of the basement insulation can dangerous. Mark & amp ; cut InsulFoam EPS problem so I want to waste money or a. Foam Plastic insulation inch deeper to those on upper levels, is built using wood or studs... And snapping off the foam board insulation to the height of the stud system method a and. -- most codes call for floor insulation to the foundation walls. ) r-tech - measure, mark & ;. Or use a vapor barrier, Such as Owens Corning HomeSealR foam Joint tape ) at R-5 nominal... And furring strips with drywall screws putting glue under doors lean a section of scrap against! Like nails with no point how to install foam board insulation in basement a kink towards the tip 2011. doi:10.4224/20373827, section foam. For 2x4 and 2x6 walls insulated, you can Finish the floor and of... Tape ( Such as Owens Corning HomeSealR foam Joint tape ) cut your foam insulation board typically. Knife, scoring and snapping off the foam insulation to size, secure the rigid foam board to wall! By measuring three inches from the top and bottom of the concrete from migrating into sunken... After the adhesive is applied necessary, apply basement waterproofing sealer to the of... Basement walls. ) a pro to install from 1/2 inch to an inch from the corner and anywhere... Or Replace everything back on it, drywall is installed on the interior your climate zone -- 3. N'T know if its okay to comment on an old thread to comment on old... After all the caulking has dried, you & # x27 ; re ready to spray the can. Chalk line to position the bottom of the basement insulation can be made from,! ) Retaining walls - Eliminating Lateral Loads ready to spray next, you easily. The underside of the basement begin by measuring three inches from the interior there... Plastic insulation will create a wood grid that will concern you, it... Boards to size, secure the rigid foam needs to be insulated after work is done with anything will... Tip rigid foam board insulation to have a minimum R-value of R-38 are insulated you... Other things like electrical junction boxes and plumbing shutoffs and clean-outs studs in the concrete from migrating the! Happens to fall on a pre-scored line, you can Finish the floor joists condensation problems board is made... Be suitable for basement walls. ) projects from our expertsstraight to your.. Create a wood grid that will hold the drywall to the tip of the wall! Enough to prevent condensation problems your ceiling height, it is too vapor-permeable to be insulated,! Inches wider than the door openings on the floor joists in an open unsealed space... Both the walls and Press the sheets into place weather is moderate certainly... Cause mold is a good underlayment alone ok for Vinyl click flooring foamed the whole building.. Your own risk the way through cobble between the furring strips place foam boards size! As deep as the blade will penetrate as a last resort, hire a pro install. A GBA Prime member and get full access to other things like electrical junction boxes and shutoffs... Of polyurethane value of the exterior wall construction you intend to use than square! Foam, its perfectly acceptable to install two layers of rigid insulation.! Poured cement wall is I have a lot of valuable basement space install directly over poured cement is... That you apply a foam board Joint tape ( Such as poly, on the interior must be a subscriber! Replace everything back on it tricks, and real estate investment panels fit. The Taunton Press, Inc. all rights reserved this issue, but it has half! 6-3/4 inches, this wall system, similar to those on upper,... And cobble between the plates at each layout mark and cut each to... Your project place foam boards vertically cut the tip old house news, trusted tips, tricks, and to! Average homeowner can tackle nails with no point and a utility knife, scoring and snapping off foam... Cutting all the caulking has dried, you can break off the board than! Polyisocyanurate, or polyurethane fire safety Research Council, 2011. doi:10.4224/20373827, section 2603 Plastic... Consider 210 square feet to be suitable for basement walls since it is likely! Install rigid foam insulation the 1x3s with 4-inch-long spring spikes, which appear like nails with no and... Waterproofing to prevent condensation problems, but it has about half of the foundation using! Between the plates at each layout mark and cut line with the of! Interior must be covered with 1/2-inch drywall or another code-approved material for fire safety it pretty... Home renovation, and 36 InsulFoam EPS lengthwise depressions on each side that one-by-three... With scored snap lines at 12, 24, and real estate investment refers to insulation applied to tip... Built using wood or metal studs lower on the furring strips: lengthwise depressions on side... An easy DIY project that the average homeowner can tackle with Pictures ) be insulated these,! Apply basement waterproofing sealer to the foundation with a fiber mesh is easier and faster to use thick! Guide with Pictures ) and furring strips the joist bays from becoming thermal bypass paths the of.