Installing cement board correctly is the most critical part of a firstclass tiling project. Cement board comes in 3by5 foot sections and installs similarly to drywall. Made from alkaliresistant, polymercoated glassfiber mesh, the tape is crackresistant and can ensure the job gets done right the first time. Take the remainder of your thinset mortar and use it to mortar the wire mesh tape to the face of the board along the edges of the joints with the flat side of the trowel. Both edges forming the seam should be supported by a common stud. Hardiebacker cement boards present a perfect substitution for traditional plywood and plasterboard substrates, due to the increased dimensional stability, strength and overall improved moisture and mould resistance. Durock brand tile backer tape is specifically engineered to provide a strong, longlasting hold for interior and exterior cement board joints, corners and abutments. What is the best way to finish the corner joints between the cement board and drywall. When i tore down the old tile and cement board i found a vapor barrier tacked to furring. Taping cement board jointsstep by step tutorial youtube. Concrete sealants butyl sealing tapes installation.
The backerboard seam tape is a selfadhering tape to reduce application time. Pull out a big enough piece of tape to cover the entire gap, then press the tape down on the gap. I am arguing he needs wonderboard but he is refusing because of the extra height. Since the width of the back wall was a little more than 5 feet wide we simply installed a full panel without having to trim it. Then a coat of thinset gets flat troweled over the seam. Quikjoint is an over banding material fabricated and manufactured to seal pavement joints.
This is for an entrance and im worried the tiles will crack. Cement board, commonly sold under trade names such as durock, hardiebacker, and wonderboard, is now the standard underlayment used for ceramic, porcelain, or stone tile laid with thinset mortar adhesive. Feb 23, 2016 in this video i will show you how to tape joints using a membrane. Its possible to expect a 20 30 year life expectancy from a properly executed repair. Once you have filled the gap with thinset, apply fiberglass tape.
Vinyl flooring over thinset on cementfiber board forum. Sep 10, 2007 ive added a new room on the house with a concrete slab foundation. How to make the transition from cement board to greenboard. Cover the joint tape with a thin layer of thinset mortar, using a 4 or 6inch drywall knife.
I installed the hardibacker using modified thinset and roofing nails. Hi tom, first redgard is not just a marketing product. The floor will transition into the existing structure which has a perimeter foundation and therefore a wood subfloor. Can be used for seaming most types of cement backer board and tile underlayment. Click the link below and get directions to your closest sherwinwilliams store. Care must be taken during vibration not to touch the tapes, but poorly bonded tapes may be displaced even if they are not touched by the vibrator. In this video, i show you how to tape cement board joints.
Troweling a perfectly flat bed required great skill, but the reward was a. There are some aspects of tile installation that seem small or insignificant but they arent. I installed a new bathtub and a 5 piece glue on surround over 14 cement board. Three tips when using tape with decorative concrete overlays. Taping cement board joints using a membrane youtube.
Let the thinset fully cure as directed before beginning the tile installation. A 50mm alkalineresistant fibatape should be added over the joints and the tiles installed onto the boards. And that i must 1 install a type of board over the floor or 2 remove as much of the paint as possible, at least 80% or 3 use scarifier or concrete grinder. It was installed with hardibacker over the subfloor and thinset.
Mix more thinset mortar and cover the taped joints with a thin layer, using a drywall knife, similar to mudding drywall joints. Diy bathroom remodeling phase 4 cement board installation. The durock joints have been redone with alkali resistant tape and custom vesabond. Rough concrete, textured, and broom finished concrete will diminish the tapes effectiveness. Unlike sheetrock, the edges of the cement board in this case, hardibacker arent beveled at all. It should go directly over the thinset and on to the backer board on the edges. Cement board is used for most floor tile and has all but replaced plywood and drywall backer materials for walltile applications in wet areas, like showers and. Cross section construction joint consumption 1 m vandex construction joint tape 1. How to repair a damaged hardie board cement fiberboard ehow. Drive screws flush with the surface of the board, being careful not to break through mesh. The thinset and mesh tape are to strengthen the seams.
For tile backer board such as durock, wonderboard, hardiebacker, permabase, and others the seams between the board need to be treated with 2inch alkali resistant mesh tape. Other than that its been my experience that hardibacker is a little easier to work with, the screws seem to counter sink more evenly than they do with cement board. How to use redgard liquid waterproofing and crack prevention. Quik joint 2 inch asphalt crack repair tape for sale. The traditional method of installing ceramic tile called for setting it in a solid mortar bed. Installing cement board underlayment for tile flooring. My contractor placed blue painters tape on the concrete for a few days to mark the placement of cabinetry. But these problems can be avoided by this one simple step. They were bulging down the middle so we shimmed and screw threw the shims. Otherwise, use latex or acrylic modified thinset mortar.
Cement backerboards include hardiebacker, durock, fiberboard, wonderboard, and similar products. I taped and covered the joints with modied thinset. A few days later the concrete was discolored and had evidence of where the tape had been placed. You need to apply the tape while the thinset is still wet. One way of holding the tapes more tightly in position is by applying a gum adhesive over the surface of the tape after it has been put in place. Hardibacker board tape 100 hardibacker board tape is a mesh, selfadhesive tape that is alkali resistant. There are several reasons that i do it this way and it is very simple.
He said the 18 joints are not to allow for expansion of the hardibacker, but to allow for. Oct 07, 2011 my contractor placed blue painters tape on the concrete for a few days to mark the placement of cabinetry. Use it with all types of tile, underlayment and hardibacker. Push the mortar through the mesh tape and into the 18inch space between the backer board and the drywall. If there isnt one there, add one and fasten both sheets to it.
It is used in areas of the house with high moisture and helps protect the sheathing from water damage. Do you need to tape and mud cement board corners in dry settings. About 1 foot of it will be exposed between the top of the. These materials bridge the gap between expense and effectiveness. There are also a few tips along with why taping cement boards together is important. Many people think that the new patching material will. Were going to tile the two adjoining rooms so were laying down hardibacker on both the wood, and concrete. Usg durock cement board is not designed for use as a structural panel. How to install cement board for tile projects family. Cut fiberglass mesh tape to fit in a single layer over every joint where the panels meet, but do not overlap the tape. Complete the job by piecing in any missing drywall and taping the seams. Patch use the cementbased, rapidsetting patching compound recommended by the floor covering manufacturer. When installed properly they will give you many, many years of durable shower construction.
Force it into the gap and apply a thin layer on both sides of the joint for a. I just completed installing 14 hardibacker over a plywood subfloor in my master bath in preparation for installing 12x12 porcelain tile. We ripped out the soffit as there was nothing in it and had to patch it up with compound. Force it into the gap and apply a thin layer on both sides of the joint for a total width of 3 to 4 inches.
Can you use joint compound to mud and tape hardibacker. Quikjoint is an innovative rollout cold applied asphalt crack repair tape that creates a durable, watertight and elastic seal after being heatbonded to the pavement surface. Quick joint crack tape is an innovative roll out strip sealer that creates a durable, watertight seal after being heated to the pavement surface. Tape the joint between backer board and drywall with fiberglass mesh tape. Jul 17, 2017 mix thinset mortar according to the manufacturers instructions and apply a thin coat over the fiberglass tape with a drywall knife. Also, when applying to concrete the smoother the concrete, the better it will work. If you are going to tile over the cement board, you should tape the seams. Smooth the mortar so it is flush with the surrounding surfaces. Installer is putting hardibacker 14 over wobbly wood floors. The cement board goes all the way to the ceiling on all sides.
I prefer mesh to even, butted joints but for many of the others i used this crack tape. Let the repair dry for a minimum of 24 hours before installing tile on top of it. Joint compound, not thinset on cement board in shower. After the mortar has slightly hardened, scratch the mortar to a thickness of 18 inch and allow the now thinned layer to dry and harden for 48. Its speciallyblended, hightack rubberized asphalt compound is compatible with all common pavement surfaces such as asphalt or concrete. The trick to a longlasting concrete repair lies in bonding the new material to the old material. Do not use 14 usg durock cement board for wall or ceiling applications. What is the best method of attaching the hardibacker to the concrete. It is not designed to bridge cracks or act as a structural membrane. Cut drywall to fill in between the existing wall or ceiling and the cement board. Permanent concrete repairs are possible, well, nearly permanent. What do you do with the seams in between durock, permabase, hardiebacker, and wonderboard. If you use redgard simply stop the backer above the flange, silicone between the flange and the backer, then paint redgard all the way down over that including the bottom of the backer and onto the flange itself.
Dec 19, 2018 fill the gap between the boards with mortar using the 6inch taping knife. Fibatape cement board tape howto install cement board tape. The tape is selfadhesive and will stick to the durock panels. Hardiebacker cement boards installation instructions.
Patching tape product list add to requisition list. As much as possible, i try to install products exactly how the manufacturer suggests. Installing cement backerboard is one of the more popular choices for a shower wall substrate. Provide support behind seams that run parallel to wall framing. Cover all of the corners, joints and seams, including the joint where drywall and cement board meet, with the fiberglass mesh tape. The tape was removed and the concrete was sealed with two coats of 25 percent solids acrylic sealer and two coats of acrylic finish. Sep 17, 2018 tile backer board may be drywall or cement board. Cement board is a type of backer board that is installed under ceramic tile. Perfect 90 drywall joint tape inside corners p90100. You can do this at the same time as tilesetting, or it can be done ahead of time and allowed to set. The importance of a properly installed backerboards the floor elf. He jumps and it shakes with the hardibacker in place. They include a patented mouldblock technology which only expands their application to even the wettest areas such as. If the gap in the joint exceeds 38, call the precast concrete manufacturer.
The joint between cement board and greenboard is similar to the. Embed 2 in wide highstrength alkaliresistant glass fiber tape in the mortar and level. Before you can replace either material, you have to expose it by removing tiles. Custom building products levelquik concrete leveler 50 lb. Protapes pro flex flexible butyl all weather patch and shield repair tape, 50 length x 2 width, white pack of 1 4. Dirty or wet concrete will prevent this and any tape from working. Quick joint crack tape is a specially blended high tack rubberized asphalt compound that is compatible with all pavement surfaces. If the gap is within 38, place new sealant and reset the casting. The importance of a properly installed backerboards. The above seems right except for the rosin paper and stapeling of 14 underlayment cement board is primarily used in areas with high moisture like bathrooms and kitchens prior to the installation of tile it is perferred by better contractors over greenboard which is a moisture resistant form of drywall it also costs more. Before installation, i used a beltsander and sometimes a power planer to smooth the transition between plywood. In this video i show you how to tape and fill cement board jointsboth cross joints and the beveled joints.
In the past, when ive done this, i had a rough time getting a relatively flat surface. Doing them improperly can lead to big problems down the road. Maximum installed weight of the finish system should not exceed 15 psf. American concrete institute 2020 aci collection of concrete codes, specifications, and practices. We recommend 14 in hardiebacker ensure subfloor is not. If you have additional comment on backerboard seams i would. Run the drywall knife over the mortar to create a smooth finish and remove any excess material. One way of holding the tapes more tightly in position is by applying a gum.
Push the plastic tightly into the corners before stapling to avoid creating a bridge of plastic that will tear when you. Cover the seams with mesh tape, such as what is used for installing drywall. When you tape and thinset your backerboard seams it will lock the two separate. The way you treat your backer board seams is one of them. At least 20 cm overlap which is glued with vandex bb.
In this video i will show you how to tape joints using a membrane. The first step in applying the stucco is to apply a scratch coat of mortar. The tape will help disperse any movement of the substrate, therefore decreasing the probability of popping or cracking tiles along the seams. How to repair uneven cement boards home guides sf gate. This is similar to mudding drywall joints but doesnt have to look as nice. Apply cement board joint tape to all of the joints between sheets, adhering the tape with its selfadhesive backing. Contact conseals technical staff for installation instructions that meet your specific. A single roll of hardiebacker fibatape, the tape is alkaline resistant with a glassfibre mesh reinforcing tape. How do you prevent the displacement of tape at the joints during placing and vibrating. Quik joint 4 inch asphalt crack repair tape for sale. Mar 27, 20 learn how to tape seems between hardiebacker board. And also the 2 vertical joints where the cement boards meet in the corners.
Mix thinset mortar according to the manufacturers instructions and apply a thin coat over the fiberglass tape with a drywall knife. Hardibacker joint cmpd a fiberglass mesh tape is placed across the joint, then you use an acrylicmodified thinset and press it into the joint, covering the tape. Do not use usg durock cement board with vinyl flooring. What good does spacing hardiboard edges from oneanother do if you then follow up the installation by filling the gapped edges with thinset and overlay with fiberglass tape, assuming the required gapping is to accomodate expansion of the substrate. Waterproofing tape for construction joints and cracks economical and safe can be applied onto damp substrate resistant to hydrostatic pressure permanently flexible can be bonded to concrete surfaces with vandex bb 75 e waterproofing slurry simple tape joints bonded with vandex bb 75 e product description vandex construction joint tape bridges and. This tape is intended for use on smooth concrete, such as interior smooth finished concrete. When you buy cement board it requires the same installation materials as drywall but with a twist. After reading a number of article online, it appears that i cannot install tile directly on top of painted concrete floor because the mortar may not bond well to the concrete and tile. If theres a big gap, ill apply spackle mixed with mud first and get it in as deep as i can, and then i apply mud after it dries, then this tape to wet mud. The procedures for patching cement board and patching drywall are similar, but you need different tools to cut the two materials. All that i did was press the tape against the part where the cement boards meet, and then use a putty knife to spread some. How to install cement board for tile projects family handyman.